JOI Glossary of Terms



abscess (Latin: abscessus)

n: an abscess is an immunologically contained and controlled lesion that is an accumulation of pus (neutrophils) in a pocket found in tissue due to inflammation induced by either (1) a localized infection caused by bacteria or parasites or (2) foreign materials lodged in the tissue. It is a defensive mechanism to prevent the dissemination of infection to other parts of the body.

absorbed radiation dose

n: (also known as total ionizing dose, TID) the quantity of ionizing radiation (measured in the joules [unit of energy] per kilogram or gray [GY] units) that a patient absorbs during a diagnostic or therapeutic radiation. The absorbed dose is dependent upon (1) the incident radiation and (2) the absorbing material (ie, an X-ray beam may deposit 4 times the radiation dose in bone than that deposited in air, or none may be deposited in a vacuum).


n: (also known as total ionizing dose, TID) the quantity of ionizing radiation (measured in the joules [unit of energy] per kilogram or gray [GY] units) that a patient absorbs during a diagnostic or therapeutic radiation. The absorbed dose is dependent upon (1) the incident radiation and (2) the absorbing material (ie, an X-ray beam may deposit 4 times the radiation dose in bone than that deposited in air, or none may be deposited in a vacuum).

abutment analog

n: a replica of the dental implant abutment that is used when making an impression for laboratory fabrication of the definitive implant abutment. The implant abutment may be made of brass, aluminum, steel, or plastic.

abutment driver dental implant

n: an instrument used to secure or remove the abutment screw that fastens the implant abutment to the implant fixture.

abutment screw, dental implant

n: a component that fastens the implant abutment to the implant fixture (body).


n: an accumulation of plaque, calculus, or material alba on teeth or dental implants.

acquired centric occlusal position, relation

n: a habitual position of the jaws that has come about by parafunction, habit, or adverse prosthetic wear. The teeth may or may not be in maximum intercuspation.

acrylic resin

n: a thermoplastic polymer of acrylic acid or congeners (acrylic acid, methacrylic acid, or acrylonitrile).

acrylic resin veneer

n: a thin covering (lamination) made of a polymer of acrylic acid for the facial or buccal surfaces of a tooth or prosthesis that enhances functional or cosmetic appearance.

Actinobacillus actinomycetemcomitans

n: a periodontal, peri-implant pathogenic bacterial species found in plaque that is subgingival or at the margin of the tooth or prosthesis. It is a gram-negative, nonmotile, rod-shaped facultative anaerobe that is often associated with aggressive periodontal diseases.

Actinomyces israelii

n: an opportunistic pathogenic bacterial species that is characterized as a non- spore-forming anaerobic bacillus, gram-positive, rod-shaped, nonmotile, and non-acid fast.

Actinomyces viscosus

n: a pathogenic bacterial species that is catalase-positive, gram-positive, facultative anaerobic, nonmotile, filamentous, and pleomorphic. It is an indigenous microflora that colonizes the mouth of humans and is often affiliated with gingivitis, periodontitis, and root caries.


n: a subacute to chronic bacterial infection caused by Actinomyces. A common form is cervicofacial i.e., lumpy jaw.

active eruption

n: see under eruption, dental.

adaptation syndrome

n: the body’s short- and longterm response to accommodate stress.


n: a lymph node that is inflamed.


n: swelling of a lymph node.


n: physical process of attachment of a substance to the surface of another substance usually due to a molecular attraction that exists between the surfaces.


n: a substance that binds or adheres surfaces together.


n: inability to make rapid opposing movements of muscules, such as jaw opening and closing.

adipose atrophy

n: wasting away of fat tissue.

adjunctive treatment

n: supplemental or additional therapeutic treatments used in conjunction with the primary treatment.

adjustable anterior guidance

n: the anterior guide portion on a dental articulator that allows for variable (individualized) settings that provide guidance for the occlusion in protrusive and lateral protrusive movements.

adjustable articulator

n: a dental articulator that is adjustable in the sagittal and horizontal planes to duplicate or simulate recorded mandibular jaw movements.

adult periodontitis

n: see under periodontitis.

age atrophy

n: a wasting or decrease in size or physiological activity of the body related to the normal aging process.


n: failure of a body part to form.

aggressive periodontitis

n: see under periodontitis.


n: a growth-related defect characterized by a severely undersized mandible or no mandible.

air abrasion

n: a wearing a way of a material’s surface due to particulate material carried by an air current.

Akers’ clasp

n: the archetypal direct retainer for removable partial dentures that comprises a rest, guide plate, retentive arm, and reciprocal arm. Akers’ clasps are traditionally directed away from the area that is edentulous. If they are directed toward the edentulous area, they are termed reverse Akers’ clasps. This clasp was named after its inventor, Polk E. Akers.

ala nasi

n: the expanded outer wall of cartilage on the lateral aspect of the nose.

ala-tragus line

n: a line that runs from the inferior border of the ala of the nose to a point on the tragus (usually the tip) of the ear. It is often correlated with the tragus of the opposite ear. It is used in determining the ala tragus plane. The ala-tragus and occlusal planes should be parallel. When viewed in the mid-sagittal plane the occlusal plane is approximately at a 10-degree angle to the Frankfort horizontal plane.


n: a dental impression material derived from seaweed that sets as an irreversible rubbery mass. Frequently, a gypsum material is poured into the set impression to form a cast that reproduces a patient’s dental anatomy.


adj: antigenically distinct individuals or tissues from the same genetic species.


n: a graft material used to augment a tissue that is from the same species but genetically dissimilar individuals.


n: an inorganic material that surgically replaces or augments missing tissue.

all-polymer prosthesis

n: a nonmetallic or nonceramic removable or fixed dental prosthesis composed of a glass fiber-reinforced composite framework with a particulate composite resin covering or overlay.

altered cast

n: a technique where a removable partial denture frame is related to the existing dentition by sectioning the cast on which the frame was constructed. A new overimpression is made and pieced together with the existing cast.

aluminous porcelain

n: a ceramic material with >35% aluminum oxide (by volume) glass matrix phase


adj: the portion of jaw bones that support teeth or that supported teeth at one time.

alveolar augmentation

n: surgical placement of bone augmentation material(s) to increase or alter the volume of the alveolar bone.

alveolar bone

n: the bone of the jaws that support teeth or that supported teeth at one time.

alveolar process

n: the (alveolar) portion of jaw bones that support teeth or that supported teeth at one time.

alveolar ridge

n: the ridge portion of the jaw bone that support teeth or that supported teeth at one time.


n: removal of all or a portion of the alveolar process of the jaw bone(s).


n: the surgical procedure of altering the alveolar ridge or its surrounding bony structures by cutting, smoothening, or reshaping to correct the alveolar ridge external contour in preparation for prosthetic rehabilitation.


(pl, alveoli) n: the socket or cavity in the alveolar bone of the jaws that supports a natural tooth.


adj: having no rigid shape or organized structure.


v: the intentional surgical removal of diseased tissue; relating to dentistry may be amputating a root from a multirooted tooth or the removal of a portion of a root.


n: a process through which circulating bacteria, pigments, metallic substances, foreign proteins, and other materials are fixated to areas of inflammation.


n: decreased ability to sense pain without the loss of consciousness.


(analogue) n: in dentistry, an implant-related device or part that is equivalent to or replicates a segment of an implant body or abutment. Typically, it is made of brass, aluminum, steel, or plastic and is used in the fabrication of the dental prosthesis.


n: patient’s recollection of their past medical history.


n: in electrophoresis, it is the movement of anions (negatively charged particles) in a solution or suspension toward the anode.

anatomic crown

n: the segment of a natural tooth that is superior to the cement-enamel junction.

anatomic landmark

n: a significant anatomic structure that is used as a reference point or orientation guide.

anatomic occlusion

n: prosthetic tooth (teeth) with an occlusal surface design that mimics the anatomic form of natural teeth.

anatomic teeth

n: prosthetic teeth that mimic the anatomic form of the corresponding natural teeth. The teeth have either a modified occlusal form with cusp inclines that are ≤20-degrees or an occlusal form with 30 to 45-degree usage cusps.

ANB angle

n: the angle formed by the anatomic landmarks nasion A line and nasion B line. The lines and angle are determined with a cephalometric analysis.

anchorage area

n: an anatomic surface that may provide retention for an oral prosthesis.

anchorage component

n: a part or device that provides resistance to an imparted force.

ancillary prosthesis

n: a prosthesis that aids in treatment and is intended for short-term or special usage. It is not the definitive prosthesis.

angled abutment

n: a dental implant abutment that diverges away from the long axis of the implant fixture.

Angle’s classification of malocclusion

n: a categorization of malocclusions according to the anteroposterior relationship of the dental arches:

  • Class I malocclusion (neutrocclusion): characterized by a normal relationship between the dental arches where the mesiobuccal cusp of the maxillary first permanent molar occludes into the buccal groove of the mandibular first permanent molar. A Class I malocclusion is presented as an internal derangement (eg, crowding) in one of the arches.
  • Class II malocclusion (distocclusion): characterized by an interarch relationship where the mandibular dental arch is positioned posterior to the maxillary arch. The mandibular first molar is distal to the position seen in neutrocclusion.
  • Class II, Division 1 malocclusion: the maxillary incisor teeth are in labioversion.
  • Class II, Division 2 malocclusion: the maxillary central incisors are in linguoversion.
  • Class III malocclusion (mesiocclusion): the mandibular dental arch is positioned anterior to the maxillary arch. The mandibular first molar is located mesial to the position seen in neutrocclusion.

angular cheilitis

n: an inflammation characterized by redness and fissures at the commissures of the mouth (aka perleche).


n: a severe restriction of tongue movement as a result of shortness or adhesion of the tongue frenulum to alveolar ridge or the mucosa on the floor of the mouth.


n: immobility, fixation, and/or joining of a bony joint or joining of tooth to bone because of an injury, disease, or surgical procedure.


v: to heat a material followed by cooling in a controlled fashion to improve the material’s physical properties. The process results in (1) degassing; (2) removal of internal stresses providing the required amount of toughness, temper, or softness; and (3) driving impurities from the surface of the material.


n: the congenital absence of deciduous (primary) and succedaneous (permanent) teeth.

antagonist tooth

n: the tooth in the opposing jaw that articulates with the subject tooth in centric and/or eccentric movement.

anterior guidance

n: how the lingual surfaces of the maxillary anterior teeth affect the excursive movements of the mandible when in contact with the incisal edges of the mandibular anterior teeth.

anterior guide pin

n: the rigid part of an articulator that is attached to one member and contacts the anterior guide table found on the opposing member. It is used to (1) establish the predetermined vertical dimension, (2) prevent wear and fracture of mounted cast’s teeth, and (3) provide guidance (in conjunction with the guide table and condylar elements of the articulator) for the horizontal movements of the articulators’ separate members.

anterior guide table

n: a flat adjustable device in one member of the dental articulator that receives the guide pin of the other member and establishes a base for recreating anterior guidance.

anterior nasal spine

n: an anatomic landmark that is a sharp protruding bone formed by the frontward prolongation of the left and right segments of the maxillae. It is adjacent to the inferior border of the anterior orifice of the nose.

anterior open occlusion

n: an absence of contact of opposing anterior teeth or their substitutes in any jaw positions.

anterior programming device

n: a custom-made device placed between the opposing anterior teeth to separate them and eliminate their influence on the naturally programmed jaw muscles with the intent of deprogramming the muscles and, therefore, changing the habitual jaw position to a more physiologic position.

anterior protected articulation

n: an occlusal scheme where the anterior teeth are in contact in all lateral and protrusive excursive jaw movements while the posterior teeth contact only in the static position of centric occlusion.

anteroposterior curve

n: an imaginary line passed through the functional cusp tips of the posterior teeth to the tip of the cuspid tooth on the ipsilateral side that forms an approximate curve.

Ante’s Law

n: eponymous (Irwin H. Ante) term that postulates that the total in-bone root surface of the supporting teeth for a fixed partial denture should be equal to or greater than the total in-bone surface area of the missing tooth or teeth being replaced; additionally, the total in-bone root surface of a removable partial denture abutment tooth or teeth plus the mucosal area of the supporting soft tissue should equal the total in-bone surface area of the teeth being replaced.


n: a feature in implant design that prevents rotation of fastened parts. This feature may be found within the implant body and within prosthetic components.


n: an anatomic cavity within bone, such as the maxilla.


n: an occlusal relationship where opposing posterior teeth are in occlusion but opposing anterior teeth are not in contact. (i.e. an “anterior open bite”).

apical abscess

n: a localized collection of pus and inflamed tissue located at or around the apex (end) of a tooth.

apical curettage

n: see under curettage


n: intentional surgical excision of the apical end of a tooth root.

arc of closure

n: an elliptical or circular arc representing the mandibular path of closure.


n: term derived from the words “articulator” and “condyle” describing a type of articulator that simulates temporomandibular anatomy.

arch bar

n: a rigid bar or wire used to stabilize teeth and implants and used for intra-arch fixation in the treatment of fractures of the maxilla or mandible.

arch form

n: the outline of the dental arch as viewed from a horizontal plane (i.e., ovoid, square, or tapered).

arch length discrepancy

n: an incongruent relationship between the arch size of the maxilla or mandible and the teeth present as viewed from the occlusal plane.

arrow point tracer

n: a device that traces the pattern of mandibular movement typically parallel to the occlusal plane.


n: pain in one or more joints.

arthrodial joint

n: a joint that allows for a sliding motion between surfaces.


n: a radiograph of a joint after injection of a radiopaque marker.


n: surgical formation or restoration of a joint.


n: a degenerative disease of a joint.

articular capsule

n: a ligament attached to bone enclosing the temporomandibular joint composed of an outer fibrous membrane and an inner lining of synovial membrane.

articular cartilage

n: the layer of surface hyaline coating in a bone joint.

articular disc

n: a fibrocartilaginous plate that acts between the temporomandibular joint members, the articular fossa, and the condylar head separating the articular surfaces.


n: a device that simulates the actions of the temporomandibular joints and jaws when maxillary and mandibular casts are mounted for purposes of diagnosis and construction of oral prostheses. Articulators are manufactured in several types and designs that represent various concepts and theories of occlusion and physiologic actions. There are 4 classes of articulators:

  • Class I articulator: a simple nonadjustable holding instrument that holds the maxillary and mandibular casts in a static mounted position that allows for vertical motion only. Also known as a nonadjustable articulator.
  • Class II articulator: a holding instrument that holds the maxillary and mandibular casts and allows horizontal and vertical motion of the maxillary cast but does not allow for orientation relative to the patient’s temporomandibular joints.
  • Class III articulator: a holding instrument that holds maxillary and mandibular casts and simulates condylar movements by using averages or mechanical equivalents for all or part of the movements. These instruments allow for orientation of the casts relative to the patient’s temporomandibular joints. Also known as a semiadjustable articulator.
  • Class IV articulator: a holding instrument that holds maxillary and mandibular casts and will accept 3-dimensional dynamic registrations. These instruments allow for orientation of the mounted casts to the temporomandibular joints and simulation of mandibular movements. Also known as fully adjustable articulators.


n: a chemical that inhibits secretions.


n: a loss of tissue from an anatomic site due to nonuse, nonstimulation, pressure, or nutrients.

attached gingiva

n: firm, dense, and often stippled soft tissue that is tightly bound to underlying periosteum, bone, or a natural tooth.


n: (1) a mechanical device used for fixing, retaining, and stabilizing prosthesis; (2) a retainer that is made of a metal receptacle and a part that fits precisely. The former (the female [matrix] component) is most often contained inside the normal or extended crown contours of the abutment tooth and the latter (the male [patrix] component) is attached to the denture framework or a pontic.

attachment apparatus

n: the anatomic complex around a tooth consisting of the cementum, alveolar bone, and periodontal ligament.

attachment level, clinical

n: when a clinician is performing a periodontal diagnostic probing, it is the distance measured from the end of a periodontal probe and the cementoenamel junction of the tooth being examined. The measurement is an indicator of the health of the supporting soft tissue attachment apparatus. See attachment level, relative.

attachment level, relative

n: when a clinician is performing periodontal diagnostic probing, it is the distance measured between the end of the periodontal probe and a set reference point on the tooth of interest or a stent. The measurement is an indicator of the health of the supporting soft tissue attachment. See attachment level, clinical.

attachment screw

n: a device that is used to fasten a nonremovable dental prosthesis to a dental implant abutment(s).


n: (1) the action of weakening and/or wearing down by rubbing or friction; (2) the mechanical deterioration and erosion of the occlusal surfaces of the teeth as a consequence of chewing or parafunction; (3) the physiologic deterioration, wasting, or wearing away of a material or structure, such as the teeth.

auricular prosthesis

n: a removable synthetic maxillofacial prosthesis made by an anaplastologist that replaces part or the entire natural ear also called artificial ear, ear prosthesis. These prostheses are typically fabricated from silicone and attached with adhesive or titanium implants.

auriculotemporal syndrome

n: a congenital or acquired condition (especially after surgery on the parotid gland) characterized by sweating and flushing in the periauricular and temporal areas when certain foods are eaten; also known as Frey’s syndrome, Baillarger’s syndrome, Dupny’s syndrome.


adj: originating or derived from within the same subject; not derived from an external source; self-produced, autologous, endogenous.

autogenous graft

n: tissue taken from the patient’s own body and moved to a different site than its origin also called autograft or autotransplant.


v: the creation of a glazed surface on a ceramic restoration by increasing the firing temperature to generate surface flow. Also called overglaze.


n: a tissue graft taken from a site that is different from the recipient site of the same individual receiving it. Also called autochthonous graft, autologous graft, autotransplant, and autoplast. See graft.


adj: (1) pertaining to self; defining products or components derived or transferred from one anatomic location to another within the recipient, (2) autogenous.

autologous mixed lymphocyte reaction

n: a proliferative reaction of typical T-lymphocytes when cultured simultaneously with autologous HLA-DR positive non-T-lymphocytes.


n: a resin polymerized by a chemical reaction that occurs by adding an activator and a catalyst without adding heat.

avascular (nonvascular)

adj: lacking blood or lymphatic vessels. Avascular tissues may be normal, such as tooth enamel or some forms of cartilage, or may be a consequence of disease.

average axis facebow

n: a device that transfers the relationship of the maxilla and the mandibular axis of rotation to an articulator by recording standard anatomic landmarks for determining the transverse horizontal axis of the face.

average value articulator

n: an articulator that permits motion based on 3 mean mandibular measurements: an intercondylar distance of 10-11 cm, a condylar guidance of 33°, and an incisal guidance of 9-12°. Also know as mean value articulator or Class III articulator.


n: a forced and aggressive separation from the body; the action that results in a separation of a body part surgically or accidentally (i.e., the complete separation of a tooth from its alveolar socket).

avulsion fracture

n: a separation of bone (or portion of bone) from its naturally occurring position by trauma or unintended force(s).

axial contour

n: the shape of a body in the dimension of its long axis. For a tooth it is the outline of the vertical portion of a tooth from the cementoenamel junction to its height of contour.

axial inclination

n: in dentistry, the angle made by the long axis of a tooth, dental implant, or other object (i.e., implant guide pin) as it relates to a specified horizontal plane, such as the supporting bone or occlusal plane.

axial loading

n: the occlusal loading forces directed down the long axis of a natural tooth, dental implant, or other object.

axial reduction

n: removal of tooth structure or its prosthetic equivalent (i.e., implant abutment) along its ideal long axis. The location and amount of reduction depends on the reason for altering or preparing the tooth or other object (i.e., preparation of teeth for restoration with a crown or alteration of a tooth in order to provide a guide plane for a partial prosthesis).

axial surface

n: the outer surface of a tooth, dental implant, or implant abutment head that is oriented with its long axis.

axial wall

n: the surface of a tooth or implant abutment that correlates with its long axis.


n: an actual or imaginary central straight line passing through the center of a body (i.e., jaw bone, tooth, dental implant, or implant abutment) around which the body could rotate if it could revolve.

axis of preparation

n: the prepared or intended path of insertion and removal for a dental restoration as it relates to its axial surface.

axis orbital plane

n: the horizontal imaginary line or plane determined by the transverse horizontal axis of the mandible with a point on the inferior margin of either the left or right bony orbit (orbitale). This plane is used as a horizontal orientation point to position teeth and/or dental implants in the ideal horizontal position in relation to the temporomandibular joint and face.


balanced articulation

n: bilateral anterior and posterior occlusal contacts that occur simultaneously when the teeth are in centric and eccentric positions. This is determined not only by positions of the teeth but also by the influence of the temporamandibular joint.

balancing interference

n: (1) tooth contact not in harmony with balanced articulation on the side of the translating condyle as the mandible moves in lateral excursions; (2) unwanted contact(s) of opposing occlusal surfaces on the nonworking side that are not in harmony with balanced articulation.

balancing side

n: the side from which the mandible moves (opposite the working side or primary chewing side) during lateral excursion.


n: a straight or curvilinear piece of metal of greater length than width. It may be used as one or more of the following: lever, barrier, fastener, handle, or supsupport. In dentistry, it is used to join 2 or more parts of a removable or fixed dental prosthesis or as a connector between dental implant abutments that may be used to retain a removable prosthesis.

basal bone

n: the portion of the mandible and maxillary bones that excludes the alveolar process.

base metal

n: any metallic element that is subject to tarnish and corrosion. See also noble metal.

base metal alloy

n: an alloy composed of nonnoble metals.


n: a rigid, comparatively thin layer of wax, shellac, or thermoplastic (heat, chemical, photo activated) polymer that conforms to the edentulous surface of a definitive cast. It is often intended to be a base that can have a wax occlusion rim or similar material, attached for the purpose of recording a jaw position and/or setting prosthetic teeth in wax for try-in. See also record base.

baseplate wax

n: a wax that has sufficient stiffness so as to be usable for making occlusion rims or waxing dentures or for performing other related procedures.

basket endosteal dental implant

n: an endosteal dental implant with a body that is shaped like a perforated cylinder.

Behcet’s syndrome

n: a condition that is more common in men than women and is characterized by recurrent genital and oral ulcers plus ocular inflammation. The definitive cause is unknown.

Bennett angle

n: the angle between the sagittal plane and the condylar path on the balancing side during lateral mandibular movements.


n: the site where a division into 2 parts occurs, as where a tooth divides into 2 roots.

bilateral balanced articulation

n: the concurrent and synchronized anterior and posterior occlusal contact of teeth on both sides of the mouth in centric, lateral, and protrusive positions. Also known as balanced articulation.


n: a device to measure biting force that has a central bearing plate of adjustable height.


n: a condition that occurs when ceramic implant materials are used and there is no space (gap) between the bone and dental implant.

biologic width

n: the total width of junctional epithelial attachment and connective tissue formed proximal to the tooth and superior to the crestal bone.


n: (1) the study of mechanics as it relates to a living structure, specifically the forces exerted by muscles and gravity on skeletal structures; (2) the analysis of biology from a functional aspect; (3) engineering principles applied to living organisms.


n: statistical analysis of biological data.


n: a tooth- and tissue-borne dental device typically made of acrylic and wire and worn in the palate and over the occlusal surfaces of the teeth and used as a diagnostic or therapeutic adjunct.

Black triangle

n: an inter-implant embrasure space devoid of a papilla. This may occur when there is an inter-implant crown contour that is shaped in a way that is not conducive for gingiva to fill the embrasure. It may be necessary to wait for 3-24 months for an embrasure fill to occur.

blade endosteal dental implant

n: a dental implant placed in bone. It has a wedge-shaped body that is narrow in a buccal-lingual direction with openings or vents in its body through which tissue may grow. An abutment portion transverses the mucogingival tissues that offer support or retention of a dental prosthesis. It may or may not be osseointegrated.

blade implant

n: see blade endosteal dental implant and implant, oral.

bleeding on probing

n: a clinical examination parameter of the natural tooth or implant gingiva or soft tissue sulcus that is used to evaluate the health of that tissue. Lack of bleeding on probing may indicate health but bleeding may or may not indicate diseased tissue. A probing force of 0.25 N is generally accepted as the appropriate probing force.

block out

v: (1) removal of unwanted undercuts on a cast. (2) the activity of applying wax or another similar provisional substance to portions of a cast that have unnecessary or unwanted undercuts. Desired undercuts that are essential for fabricating the prosthesis are left as such.

bone atrophy

n: a decrease in bone mass exhibited as resorption that is represented internally by a decrease in density and externally by a reduction in form.

bone conduction

n: the transmission of sound from the skull bones to the inner ear. Also known as cranial conduction, osteotympanic conduction, and tissue conduction.

bone curettage

n: the surgical shaving or flattening of a bone’s external surface.

bone expansion

n: manipulation of a bony ridge with flat and rounded osteotomes for recontouring the cortical ridge to gain more bone width than originally present, usually to accommodate placement of a dental implant.

bone factor

n: relative response of alveolar bone to positive or negative stimulations; the ratio of osteogenesis to osteolysis.

bone fill

n: the clinical repair of bone tissue in a treated periodontal defect or previous bony void. Histologic evidence should confirm replacement of previously missing bone tissue with same type of bone tissue.

bone graft, autogenous

n: see graft.

bone resorption

n: see under resorption.

bony ankylosis

n: the bony union of the constituents of a joint that results in complete immobility of the joint.

border movement

n: when observed in a designated plane it is the mandibular movements at the boundaries permitted by anatomic structures. The movements are reproducible and unique for each individual. All mandibular movements are determined by the parameters of the border movements.

border seal

n: the physical contact established by the alveolar mucosa to drape the molded borders of an oral removable prosthesis in an attempt to create negative pressure that aids in the retention of the prosthesis and the prevention of the ingress of fluids, air, and food into the intaglio surface.

border tissue movements

n: the action of the alveolar mucosa aided by muscles and tissues proximal to the borders of the denture—usually recorded during border molding to determine and fashion the denture edges.


n: (1) the parafunctional grinding, clenching, or clamping of teeth; (2) a habit that consists of the involuntary recurrent or spasmodic nonfunctional grinding, clenching, or clamping of teeth in other than desired functional movements of the mandible (chewing), which results in occlusal damage. Also known as tooth grinding, occlusal neurosis.


n: the grinding or clenching of teeth occurring as a neurotic habit while awake.

buccal flange

n: the portion of the denture that extends from the cervical margins of the denture teeth to the border seal areas.

buccal vestibule

n: the fold of alveolar mucosa extending from the buccal attached mucosa to the loose areolar mucosa of the cheek.

buccolingual relationship

n: a reference to the position as it relates to the cheek and tongue in the coronal plane.


n: the divergence of a tooth from its customary alignment in the dental arch to a direction toward the cheek or lips.


n: a vesicle or blister >5 mm in diameter.


n: the ability or ease with which a material can be polished by rubbing.


v: to place end-to-end or side-to-side without overlapping, as in a butt joint.

button implant

n: see mucosal insert.

buttressing bone

n: compact or dense bone that serves to support or strengthen and may form in response to occlusal forces.

buttressing bone

n: compact or dense bone that serves to support or strengthen and may form in response to occlusal forces.



acronym for computer-aided design/ computer assisted machining or computer- aided design/computer-aided manufacturing.

calcium sulfate plaster

n: a paste composition of CaSO4 and water used as a medicated or protective dressing that hardens upon drying.

Campylobacter rectus

n: previously named Wolinella recta. Surface translocating gram-negative, motile, facultative bacteria that are frequently observed as helical, curved, or straight bacterial cells. This bacterium is found in patients with periodontitis. The bacteria display flagella located at one pole of their cell body that results in a motility that is described as rapid and darting.

cancellous bone

n: the lattice-like, reticular, or spongy or part of bone; it is the tissue found in the medulla of the bone; it has a variable trabecular pattern and is made of interstitial tissue that may be hematopoietic.

Candida albicans

n: the utmost pathogenic species of Candida, which under some circumstances may cause infections; however, typically it is an innocuous inhabitant of mucous membranes.

Candida spp

n: a yeastlike fungus frequently associated with oral diseases like thrush (oral candidiasis). It is aerobic, is significantly larger than bacteria, and stains gram-positive.

candidiasis (thrush)

n: an infection caused by the fungus genus Candida. It is associated with multiple influencing factors that include (1) the use of broad-spectrum antibiotics, (2) diabetes mellitus, (3) xerostomia, (4) suppression of the immune system, and (5) pregnancy. Clinically, it appears as soft, white, curdlike plaques that can be wiped off, leaving an erythematous area.

canine eminence

n: the facial elevation of the maxillary bone consistent with the location of the root of the cuspid.

canine protected occlusion

n: regarding implant dentistry: a tooth arrangement that protects implant- supported prosthetic crowns from off-axial loads or lateral forces that may be detrimental or cause an overload of the supporting bone. Generally, the mandibular canine cusp articulates or slides against the lingual surface of the maxillary canine to cause a separation of the posterior teeth so off-axial loads are avoided.


n: a projection supported on one end only.

cantilever fixed dental prosthesis

n: a fixed partial denture in which the pontic is suspended in a mesial or distal direction and is retained and supported only on one end by one or more abutments.

capillary attraction

n: an increase or decrease in the height of a liquid as it contacts the retaining walls of the container holding the liquid. A surface tension-dependent phenomenon.

cap splint

n: a plastic or metallic device that is cemented on to the clinical crowns; used to treat upper or lower jaw fractures.

capsular fibrosis

n: as related to the temporomandibular joint, a contracture of the capsular ligament due to a fibrotic change.

capsular ligament

n: referencing the temporomandibular joint it is a thin, loose, envelope-like fibrous band of tissue that connects the head of the mandible’s condyle with the glenoid fossa. It is attached superiorly to the circumference of the glenoid fossa, anteriorly to the articular tubercle, and inferiorly to the condyle of the mandible.


n: a positive reproduction of a needed shape created by pouring a material that hardens into a mold, matrix, or impression of the needed shape.

cast clasp

n: a clasp of a metal framework removable partial denture fabricated using the lost-wax technique.

cast connector

n: a (cast) metal part of a fixed dental prosthesis that joins the abutment(s) and pontic(s).

cast metal core

n: the base restoration (core) indirectly made by using a lost-wax casting technique for the purpose of supporting a fixed dental prosthesis. It will be cemented or bonded to the native tooth structure.

cast relator

n: an instrument that orients opposing dental models in an arbitrary manner without correlation to anatomic landmarks.

cast, study or diagnostic

n: a positive reproduction of the teeth and associated structures formed by pouring dental stone or dental plaster into a matrix or impression. It is made for the purpose of evaluating dental structures and occlusal analysis.


n: a material that can be cast in a mould. The material can be in a liquid state due to heating or mixing a powder and a liquid; once poured or injected into a mold it solidifies.

castable ceramic

n: regarding dentistry, a glass-ceramic material that can be cast using the lost-wax process technique and maintains the properties of a restorative material for function.


n: a reproduction of an object formed by pouring or injecting a fluid into a mold that then becomes a solid.


v: the technique or process of pouring or injecting a fluid into a mold that then solidifies creating a replicate of the molded object.

casting ring

n: a metal cylinder in which a refractory pattern is made and used in the casting process for a dental prosthesis.

casting wax

n: a wax composite with acceptable characteristics that can be used for making wax patterns that are placed in an investment material, once the investment has set, heat is applied and the wax is “lost” (melted) from the investment. The investment is then subject to the casting process where a liquid is poured into the investment to replace the lost wax. The liquid solidifies and the investment material is then removed, leaving a casted object that is a duplicate of the wax pattern.


computerized axial tomography.


n: applying a caustic substance, electric current, hot instrument, or other agent to burn or destroy tissue and control bleeding during surgery. From the Greek term kauterion, meaning branding iron.

cavernous resorption

n: see under resorption.

cavity varnish

n: an organic solvent (chloroform or ether) that contains a mixture of copal resin or other synthetic resins and is used to protect a tooth from the constituents of the restorative material(s).


n: a widespread inflammation; usually related to an inflammatory condition contained within loose subcutaneous tissue. Often associated with a bacterial infection and is frequently a precursor to abscess formation.

cementoenamel junction

n: the meeting point on any tooth between the root cementum and the crown enamel. See also junction.


n: the creation or development of cementum.

cementum fracture

n: the tearing or splintering of the cementum from the tooth’s root surface. Superficial disruptions of a tooth root that result in the displacement of cementum fragments.

center of ridge

n: the midline of the residual ridge in a buccolinigual dimension, as viewed from the occlusal aspect.

central bearing

n: a device that applies a single point force that is applied as centrally as possible at the center of support between the maxillary and mandibular jaws. It distributes the closing forces evenly throughout the supporting structures when recording maxillomandibular jaw relationships. It is also used to detect errors in occlusion.

central bearing point

n: the precise location of contact for a central bearing device.

central bearing tracing

n: the recorded path of motion on the horizontal plate of the central bearing tracing device.

central bearing tracing device

n: a device that is used to balance occlusal forces when measuring maxillomandibular jaw relationships or to map the full envelope of mandibular movement. It consists of a plate attached to a dental arch and a tracking device that records movement.


n: (1) located in or at a center; (2) oriented around or directed toward a center.

centric occlusion

n: the maximum balanced intercuspation of maxillary and mandibular teeth; may or may not coincide with centric relation.

centric position

n: the position of the mandible in either centric occlusion or centric relation.

centric relation record

n: a registration of the relationship between the maxilla and mandible when the mandibular condyles are in centric relation. The record may be taken intraorally or extraorally.

centric stop

n: occlusal contacts of opposing teeth that maintain the occlusal vertical dimension between the maxillary and mandibular arches.

cephalometric radiograph

n: a standardized radiograph of the head used for making cranial measurements.

cephalometric tracing

n: a line diagram that is a copy of the structural landmarks of the orthodontically relevant craniofacial markers and facial bones. It is made by drawing on a thin paper sheet placed on a cephalometric radiograph through which light is projected.


n: (1) the science of measuring the dimensions of the head; (2) in dentistry, it is determining the permutations of angles, lines, and planes that are derived from tracings of landmarks on frontal and lateral radiographic head films. The measurements are used to assess growth, development, and treatment responses of the craniofacial bones as it relates to diagnosis, in-treatment evaluations, or completed orthodontic treatment.


n: a device used to precisely and predictably position the head so as to create spatially oriented and reproducible radiographs or photographs.


n: a fine-grained glass-ceramic material that is derived from applying heat to a specific form of glass.


n: (1) a broad class of materials made from a variety of nonmetallic compounds with a metallic component, which are fired at high temperatures to achieve their physical characteristics of high hardness, brittleness, low thermal and electrical conductivity, and high corrosion resistance. They are generally oxides but can also be composed of calcium phosphates, alumina, zirconia, nitrides, borides, carbides, silicides, and sulfides, alone or in combination with glass or metals (cermets). In dentistry, the term is used liberally to include all materials that mimic the optical qualities of natural tooth structure or gingivae and have the characteristics of this class. They are also sometimes used as synthetic osseous grafting materials and biocompatible surface coatings; (2) adj: of or relating to the application of ceramics.

ceramic crown

n: (1) a fixed dental prosthesis, fabricated entirely with ceramic materials. It is cemented, bonded, or screwed to an underlying implant fixture, abutment, or framework; (2) a fixed dental prosthesis that is fabricated entirely with ceramic materials and cemented or bonded to an underlying natural tooth.

ceramic flux

n: a glass modifier that disrupts the oxygen- silica bonds and in doing so increases fluidity. The bonds are disrupted by the addition of metallic ions, such as calcium carbonate, potassium carbonate, or sodium carbonate.

ceramic onlay

n: an indirect, intracoronal restoration involving coverage of 1 or more cusps fabricated entirely with ceramic materials and generally bonded to natural tooth.


n: (1) relating to the science of manufacturing and use of ceramic, particularly bioceramic compounds; (2) the art of fabricating dental restorations using ceramic alone or in combination with other materials.


(ceramicist) n: (1) a laboratory technician who specializes in the art and science of dental ceramics; (2) a researcher who investigates ceramic materials science.


n: (1) any mixture of ceramic and metal particles used as a restorative material; (2) a ceramo-metal compound, often used as a friction-reducing coating (i.e., titanium nitride syn: ceramet)


n: a narrow or constricted portion; in dentistry it refers to the constricted region where the crown meets the root of a tooth.

chamber, pulp

n: the segment of the pulp cavity located inside the anatomic crown portion of the tooth.

chamber, pulp

n: the segment of the pulp cavity located inside the anatomic crown portion of the tooth.


n: (1) a tooth preparation line design in which the gingival aspect and external axial surface meet at an angle >90° but <180°; (2) a small channel or trench; (3) the surface that results at the obtuse angle where 2 faces of a material or preparation meet; (4) an edge that is beveled.

chamfer angle

n: (1) the angle formed by the surface plane of the prepared chamfer and the vertical component of the unprepared tooth; (2) the angle formed by the surface plane of the restorative finish line of an implant abutment and its long axis.


n: to change by applying distinct markings, indentations, coloration, and similar unique methods of demarcation on a tooth or dental prosthesis to improve the natural appearance.


v: to define in a unique, distinguishing, manner.

characterized denture base

n: a denture base with coloring that mimics the color, hues, and shades of naturally occurring oral tissues.


n: inflammation occurring in the lip.

cheilitis, angular

n: inflammation present in the corner angles or commissures of the mouth.


n: plastic surgery performed on the lip.


n: a disorder of the lips and angles of the mouth characterized by fissures; often associated with a riboflavin deficiency.


n: a chemical or biological mediator that causes movement of cells along a concentration gradient to the area with the highest concentration of the chemical.


n: a bis-biguanide antiseptic agent effective in the prevention of colonization by killing or inhibiting growth of microorganisms on surfaces of skin, mucous membranes, and teeth.

chronic abscess

n: a pus-generating infected lesion where the immunity has confined the infection and is in a quiescent state but still contains live bacteria.

chronic closed lock

n: a clinical situation where the temporomandibular joint has restricted motion over a long period of time. An anterior dislocation of the intra-articular disk causes this clinical situation. Chronic pain is typically observed.

chronic pain

n: pain marked by an extended duration or frequent recurrence. Chronic is a Greek word referring to any situation that has been present over a long period of time. During that period the described pain can periodically diminish or disappear and recur again frequently.

chronic periodontitis

n: see under periodontitis.


n: observed fibrous connective tissue that results from wound healing; a scar.

circumvallate papilla

n: see under papilla.

citric acid

n: a tricarboxylic acid that is useful as a near-saturated solution (pH = 1.4) to detoxify (cleanse) root surfaces that are contaminated and expose intrinsic collagen fibers in the hopes of achieving new tissue attachment.

clamping force

n: the compressive force applied to a bolted join by a fastener. The firmness or tightness of the bolted joint is dependent upon maintaining the clamping force.

Class I articulator

n: see under articulator

Class I malocclusion

n: see under Angle's classification of malocclusion.

Class I removable partial denture

n: see under Kennedy classification of removable partial dentures.

Class II articulator

n: see under articulator.

Class II malocclusion

n: see under Angle’s classification of malocclusion.

Class II removable partial denture

n: see under Kennedy classification of removable partial dentures.

Class II, Division I malocclusion

n: see under Angle's classification of malocclusion.

Class II, Division II malocclusion

n: see under Angle's classification of malocclusion.

Class III articulator

n: see under articulator.

Class III malocclusion

n: see under Angle's classification of malocclusion.

Class III removable partial denture

n: see under Kennedy classification of removable partial dentures.

Class IV articulator

n: see under articulator.

Class IV removable partial denture

n: see under Kennedy classification of removable partial dentures.


n: (1) a physical state in which physical masses may pass each other without interference. (2) The gap between 2 bodies.

cleft, gingival

n: a vertical opening, slit, or fissure in the gingiva.


v: the habitual and persistent holding of the jaws and teeth together under pressure. It is frequently due to nervous tension or physical effort.


n: a snapping, cracking, or audible noise generated in the temporomandibular joint by excursions of the mandible that is also detectable with palpation. Also called crepitus.

clinical crown

n: the portion of a tooth that projects above the free gingival margin.


n: a device (also called an inclinometer) for measuring angles of elevation, slope, tilt, inclination, or depression. The device is used to measure range of motion in joints and for measuring angles in the body, particularly in the pelvis, back and neck. clinometric adj; clinometry n.

closed curettage

n: see under curettage

closed lock

n: an internal (Type II) imbalance of the temporomandibular joint in which the condyle is blocked from sliding under the anteriorly and medially displaced articular disk.

closed reduction of a fracture

n: repositioning of bone fragments through manipulation only, that is, without surgical intervention.

closest speaking space

n: the interdental clearance provided by the maxillary and mandibular incisor teeth during speaking jaw motion while pronouncing fricatives and sibilants.

clutch coll

n: a device affixed to the maxillary and mandibular arches to support components that record mandibular movement.


v: in dentistry, the proper realignment of displaced parts back to their original position, as in the fractured incisal edge of a central incisor that may be coadapted and bonded back to its original position.


n: proper alignment of the displaced edges of a wound or the ends of a fractured bone.


n: taken from a geography term meaning the pass or depression between 2 mountains; in dentistry it refers to the gingival depression between the teeth that connects the facial and lingual papillae. It follows the shape of the interproximal contact in healthy gingiva.

collagen fiber

n: see under fiber.


n: a metalloproteinase that catalyzes the breakdown of collagen, a key component of the extracellular matrix. It is also responsible for the cleavage of procollagen, which is secreted by the cell during the normal process of collagen production.

collateral ligaments

n: in the jaw this refers to paired ligaments that limit motion of the lower jaw within the confines of physiologic motion. Ligaments connect bone to bone and do not stretch, so when working collaterally they limit joint movement. One example of collateral ligaments is in the temporomandibular joint, where they assist in the hinging motion of the joint and prevent the head of the condyle from popping out of the joint.


n: (1) to apply colors; (2) to produce color or color effects; (3) to apply or combine colors to produce an effect.

combination clasp

n: a clasp for a removable dental prosthesis that has a circumferential retainer comprising a wrought wire retentive clasp and a cast reciprocal (stabilizing) arm.

combination syndrome

n: the clinical changes observed when an edentulous maxillary arch is opposed by a mandible with retained anterior teeth that may or may not be extruded and missing posterior teeth. Over time, there is a loss of bone in the premaxilla, loss of bone in the edentulous posterior mandible, overgrowth of the maxillary tuberosities, and hyperplasia of the hard palate mucosa. Also referred to as anterior hyperfunction syndrome, or Kelly syndrome.

comminuted fracture

n: a complex bone fracture characterized by breaks in several places in the same area, crushed and/or splintered.


n: a meeting point or junction between 2 anatomic structures, that is, corners of the mouth. commissural adj

commissure splint

n: a device placed between the lips that helps increase the separation between the lips. Such a device is often used when surgical, electrical, or chemical damage of the lips has caused contracture or restriction of the lips. Also known as a lip splint.

compact bone

n: concentrically arranged dense bone solidly filled with inorganic salts and organic ground substance with the presence of small spaces called lacunae filled with osteocytes (bone cells).

compensating curve

n: the curve created by the alignment of the occlusal and incisal surfaces of artificial teeth that compensates for the condylar path when the mandible moves from centric to eccentric positions and provides for a balanced occlusion. The compensating curve corresponds to the curve of Spee in a natural dentition.

complementary colors

n: (1) two different colors that form a neutral color when mixed together in correct proportions; complementary colored light creates white light upon mixture in an additive process, and mixtures are determined by the laws of additive color. If complementary, colorants mixed together form gray or black, and mixtures are determined by the laws of subtractive colorant mixtures; (2) colors directly opposite on the color wheel. Complementary colorants form gray or black when mixed. Also follows the laws of subtractive color.

complete arch subperiosteal implant

n: an implant that is placed in a manner such that it rests under the periosteum of the osseous residual ridge and provides abutments that extend through the gingival tissues into the oral cavity that support fixed or removable dental prosthesis over the completely edentulous ridge. Such devices are described by how they are related to the alveolar bone, which provides support. A subperiosteal implant can be described as an eposteal dental implant. See also eposteal dental implant.

complete cleft palate

n: a cleft or opening that extends through the anterior portion of the alveolar ridge as well as the primary and secondary palates.

complete crown

n: a restoration, frequently made of cast metal or a ceramic material, that covers all 5 surfaces of a tooth—the mesial, distal, occlusal, facial, and lingual.

complete denture

n: prosthesis, usually removable, used to replace all of the dentition and related structures of the maxillary or mandibular arch.

complete denture prosthetics

n: (1) the replacement of the natural teeth in at least one arch using manmade materials; (2) the art and science involving methods of restoring the appearance and function of an edentulous mouth.

complete denture prosthodontics

n: the art and science related to knowledge and skills about restoring an edentulous arch with a dental prosthetic device.

complete facial moulage

n: a process consisting of an impression that records the soft tissue contours of the entire face.

complicated fracture

n: a break or disruption in an osseous structure that then causes an injury to adjacent structures like an organ, nerves, or blood vessels.


n: a polyacid-modified composite resin containing an acid-modified dimethacrylate resin, glass ionomer fillers, and a photoinitiator. The combination of components offers advantages over either of the separate components.

components of occlusion

n: the structures related to how the teeth interact; structures include the temporomandibular joints, related muscles, teeth, jaw bones, and other supporting or related soft and hard tissues.

compound joint

n: a joint in the body that involves 3 or more bones.

computerized tomography

(CT) n: a radiologic two-dimensional representation of a three-dimensional depiction of a patient’s anatomic structures. (See also cone beam computerized tomography.) The images formed depict anatomic osseous structures that can be measured and examined for dental implant placement. A computer is used to arrange the collected radiographic images into a single view. See also cone beam computerized tomography.


n: when the roots of adjacent teeth are joined via cementum deposits.


n: a predominantly inorganic mass in a cavity or in the tissue of an organism.


n: (1) The process of using force to ensure continuity of the matrix phase and removal of excess mercury when compacting dental amalgam.; (2) The process used to increase the density of dental porcelain by eliminating excess water through vibration and blotting.

condylar agenesis

n: a congenital anomaly depicted by the absence of the condyle.

condylar articulator

n: a device that replicates the position and movement of the jaws whereby the artificial condyle is represented by a metallic ball that interacts with a plane to represent the articulating surface of the temporomandibular joint. These articulators can be: (i) arcon instruments, where the metallic condyle is positioned in a similar manner to a naturally occurring condyle and moves against the artificial articulating surface, or (ii) non-arcon instruments, where the metallic plane moves against the metallic ball, unlike that which occurs in a human temporomandibular joint.

condylar axis

n: a theoretical line traversing through the center of the mandibular condyles and around which the mandible rotates.

condylar dislocation

n: a dislocation of the mandibular condyle, typically forward of the articular eminence; it is not self-correcting or self-reducing.

condylar displacement

n: when the location of the condyle is not in its natural position.

condylar guidance

n: (1) the segment of an articulator that is located in the superior posterior region of the nonmobile member that is designed to control the movement of the movable member; (2) the pathway that the condyles traverse through during translatory movements; the inclination of the path can be measured in degrees relative to the Frankfort plane; (3) v: during mandibular excursive movements it is the mandibular guidance created by the condyle and articular disc as they move and relate to the contour of the glenoid fossae.

condylar subluxation

n: a self-reducing incomplete or partial disarticulation of the condyle from its glenoid fossa.


n: a rounded articular prominence found on the end of a bone, that is, relating to the mandible. It is a bilateral ellipsoidal projection found on the superior portion of the mandible’s ramus, and it articulates with the glenoid fossa. The condyle sits atop the condylar neck. The combination of the condyle and the condylar neck is referred to as the condyloid process or condylar process.


n: surgery to remove the mandibular condyle.


n: intended surgical cut through the neck of the condyloid process for the purpose of removing the condyle. Also used in reference to the intended surgical excision of a portion of the articulating surface of the mandibular condyle (known as a condylar shave).

cone beam computerized tomography

n: a diagnostic radiographic modality that sends radiation as a cone that rotates about the target patient to provide a variety of images. In computerized axial tomography used in the medical community the radiation beam is flat as opposed to a cone emanation. The various target tissues absorb the radiation completely or partially and pass the unabsorbed radiation to a sensor. The sensor receives the radiation that is not absorbed, and hundreds of images are formed, termed “image acquisition.” The two-dimensional images are recorded and then reconstructed by an attached computer to deliver two-dimensional images of a three-dimensional construct. Various two-dimensional images can be acquired by selecting the desired plane from the three-dimensional construct. Thus, the dentist may interpret the images for surgical case planning and measurement of anatomic landmark location.

continuous bar connector

n: a metal bar arising from terminal rests of key abutments resting on the cingulums of the mandibular anterior teeth so that it aids in their stabilization and functions as an indirect retainer in a free end distal extension dental prosthesis.

continuous beam

n: a beam that spans over 3 or more abutments and resists bending when a load or force is applied.


n: a shortening of a muscle that is permanent and a consequence of fibrosis.


adj: relating to or pertaining to or occurring on the opposite side. The working of the opposite side in concert with similar parts on the primary side of interest; the opposite of ipsilateral.


n: a thin layering, covering, or crown; something similar to a cope (as by concealing or covering).

coping impression

n: an, impression that employs resin or metal copings on prepared teeth and most often involves an entire dental arch.

copper band

n: a cylinder made from copper and used as a matrix for making an impression.


adj: possessing the form of coral; coral- like in its branching; usually with reference to various types of implant materials made from hydroxyapatite.


adj: (1) in dentistry, relating to a tooth’s natural or prosthetic crown; (2) in anatomy, the plane that runs along the long axis of the body.

coronal plane

n: aligning in the direction of the coronal suture, the plane that separates the front from the back of the body.


n: surgical excision of the coronoid process.


v: (1) to deteriorate or oxidize a metal as a result of electrochemical reaction within its the environment; (2) gradual deterioration, usually by chemical action.


n: (1) the deterioration of a material by electrochemical reaction with the environment. The term corrosion usually refers to oxidation of metals, known as rusting, which results in a layer of oxide or salt on the surface. Deterioration often affects properties of the material, such as strength, appearance, and permeability. Corrosion can also occur in other materials, such as ceramics or polymers; (2) the action, process, or effect of corroding; a result of corroding; (3) the loss of elemental components to the bordering environment.


adj: having the power to induce corrosion.

cortical bone

n: the outer layer of osseous tissue. Cortical bone is one of the 2 categories of osseous tissue that make up bone. Cortical bone, the outer layer, is dense, in contrast to the inner layer, called cancellous bone, which is much less dense. Also known as compact bone.

cover screw

n: also known as the healing screw; the element of an endosteal dental implant used to seal the internal threaded section of a dental implant body during the healing phase. This healing screw is provisional and ensures patency of the internal threaded section for the later attachment of the implant healing collar or implant abutment head. It also helps keep the internal section free from plaque and bacteria during stage 1 healing.


n: multiple superficial cracks or loss of surface integrity that may or may not progress into complete fractures.


n: a snapping or grating noise and/or sensation in a joint during movement; related to the temporomandibular joint, a crackling sound made when one opens and closes the jaw; the noise made when the ends of fractured bone rub together.


n: a crackling or grating noise and sensation in a joint during movement.

crestal lamina dura

n: see under lamina dura.

crevicular epithelium

n: the nonkeratinized stratified squamous epithelium of the gingival crevice.

crevicular fluid

n: the fluid that is typically produced in the presence of inflammation and seeps through the crevicular epithelium; it can serve as a defense mechanism against infection by carrying antibodies and other substances into the sulcus. Also known as sulcular fluid and gingival fluid.


adj: perforated like a sieve, for example, the cribriform plate of the ethmoid sinus.

cribriform plate

n: in dentistry, the alveolar bone proper. Another example is the horizontal plate of bone of the ethmoid sinus, which is perforated by numerous foramina that allow passage of nerves through the bone.

cross-arch stabilization

n: in removable dental prosthesis design, this relates to resistance against dislodgment of the removable prosthesis during function by utilizing the natural teeth on the opposing side of the dental arch to assist in stabilization or to help prevent “tilting” of the removable appliance.


n: a dental condition where a mandibular tooth is located facial to the opposing tooth. Normal dentition locates the mandibular dentition lingual to the maxillary dentition.

crown-implant ratio

n: the ratio determined by measuring the total height of the restoration and implant above the alveolar bone compared with the height of the implant within the alveolar bone. It is typically evaluated by radiographic examination.

crown-root ratio

n: the ratio determined by measuring the total height of the tooth above alveolar bone compared with the height of the tooth’s root within alveolar bone; it is typically evaluated by radiograph.

curet, periodontal

n: a periodontal instrument with a fine blade used primarily for removing the inner lining of pocket walls and epithelial attachment. Also used for removing periodontal fibers from walls of osseous defects and removing calculus fragments and smooth root surfaces.


n: scraping, cleaning, or debriding biological material or debris from the walls of a defect or surface by means of a curette.


n: scraping, cleaning, or debriding biological material or debris from the walls of a defect or surface by means of a curette.

  • apical curettage (periapical): elimination of tissue or biological debris contiguous to an apex of a tooth.
  • closed curettage: elimination of tissue or biological debris contiguous to a tooth via entry into the gingival crevice without flap reflection.
  • gingival curettage: the process of debriding biological debris from the soft tissue wall of a periodontal pocket.
  • surgical curettage:elimination of tissue or biological debris contiguous to a tooth by the reflection of a flap.

custom tray

n: a personalized impression tray prepared from a cast derived from a preliminary impression. The custom tray is used in making the final impression.



n: physically cleansing or removing acute or chronically inflamed granuloma or other contaminated devitalized tissue or foreign material from a lesion.


n: the process of removing the mineral content from a hard tissue, such as bone or tooth, with the aid of acids.


n: demineralization of tooth structure leading to decomposition and destruction of tooth structure and then cavitation.


n: deliberate removal or repeated puncturing of cortical bone to initiate bleeding or a regional accelerated phenomenon for bone repair or to enable incorporation of a bone graft into the host bone. Method routinely used in osteomyelitis wherein after removal of the sequestrum, the surrounding vital bone is included in the removal to initiate bleeding to promote osseous healing.

decreased occlusal vertical dimension

n: the biometric decrease in the vertical relationship of the lower third of the face caused by progressive loss of tooth structure resulting in an increased interocclusal gap.

definitive prosthesis

n: any dental or maxillofacial prosthesis that will not require any further modification. Such prostheses are designed and intended for long-term use.

deflective occlusal contact

n: (1) the slide encountered from the initial point of tooth contact during mandibular closure causing a deviation in the mandible; (2) An undesirable contact that displaces a tooth, deters the mandible from its anticipated arc of closure, and/or dislodges a removable denture from its intended position.


v: to open at definite places; to split or peel down along a natural line; to rupture or discharge the contents by splitting open. dehiscence n: an act of dehiscing, a rupture or splitting open, that is, separation of wound margins.

dental articulation

n: the contact relationships of the occlusal surfaces of the maxillary and mandibular teeth when moved against each other (gliding occlusion).

dental cast

n: a reproduction; a positive copy of segments or parts of the oral cavity.

dental casting investment

n: combination of silica phosphate and gypsum bonding materials used in dentistry to enclose wax or plastic patterns during the casting process in the laboratory fabrication of dental crowns and bridges. For lower casting temperatures, a gypsum bonding material is used, and for higher casting temperatures, phosphates or silica materials are used.

dental dysfunction

n: atypical functioning of masticatory physiology; a disorder or functional impairment of the chewing or masticatory system

dental dysplasia

n: see dysplasia.

dental element

n: reference to a dental prosthesis that achieves a portion of its retention from 1 or more dental implants.

dental implant

n: (1) a device placed beneath the soft tissue layer upon (eposteal), within (endosteal), or through (transosteal) the bone to retain or support a dental prosthesis; (2) a device used to retain or support a dental abutment.

dental implant abutment

n: the part of a dental implant that functions to retain and/or support a removable or fixed dental prosthesis. Frequently endosteal dental implants have a temporary or preliminary abutment before a definitive dental abutment and prosthesis is placed. Preliminary abutments are called interim (dental implant) abutments. The final abutment that supports the definitive (final) prosthesis is called a definitive (final) dental implant abutment. Dental implant abutments are often identified by their descriptive form (ie, cylindrical, barrel), material (ie, titanium, ceramic, zirconia ceramic), or special design factors (ie, external/internal hex lock, Morse taper, or spline).

dental implant analog

n: a duplication of the entire dental implant used in the dental laboratory to assist in making a temporary or definitive prosthesis; not intended for human implantation.

dental implant attachment

n: (1) the biochemical/ mechanical connection between the dental implant and the hard and soft tissues to which it is attached; (2) vernacular for the method that provides retention of the dental implant abutment to the dental implant.

dental implant loading

n: the process of placing often intentional axial or oblique force(s) upon a dental implant. This process is usually associated with the purposeful exposure of the dental implant at the time of surgical placement or subsequent surgical exposure. Forces may be generated from a range of causes, including habitual, deliberate, and/or unintended occlusal loading; unplanned forces from the tongue or other oral tissues; mastication; and alveolar/ osseous distortion. The application of intentional occlusal forces is designated 1 of 3 types of loading: immediate, progressive, or delayed.

dental implant system

n: dental implant kit designed for the placement of the dental implant(s) and subsequent attachments of abutments that facilitate the retention of the dental prosthesis. The term can denote a specific concept, inventor(s), or patent(s).

dental impression

n: an imprint made within the oral cavity to produce a replica of the structure of interest used to make a record or to manufacture a dental restoration or prosthesis.

dental impression wax

n: a thermoplastic material used for making a dental impression.

dental plaster

n: a slightly hydrated powder of beta calcium sulfate made from gypsum that forms a quick-setting paste when mixed with water. Used in dentistry to make casts. The beta form of calcium sulfate is an aggregate of irregularly shaped porous fine crystals. Also known as plaster of paris.

dental prosthesis

n: a fixed or removable appliance used to replace 1 or more missing teeth and/or associated dental/alveolar structures. See also prosthesis.

dental senescence

n: the deterioration of teeth or other structures within the oral cavity associated with the aging process.

dental stone

n: a slightly hydrated powder of alpha calcium sulfate that forms a dense stonelike material when mixed with water. Used in dentistry to make casts. The alpha form of calcium sulfate is denser and superior to the beta form because the alpha form contains pieces and crystals in the form of rods or prisms.


n: a dense substance that forms the bulk and body of a tooth that surrounds the pulp. It is beneath the enamel and radicular cementum. It is similar to bone but harder. Also spelled dentine.

dentinoenamel junction

n: see under junction.

dentofacial orthopedics

n: the branch of dentistry that deals with the prevention and correction of abnormal jaw and tooth relationships, often by surgery.


adj: having natural teeth present in the oral cavity.


n: a prosthetic device used to replace 1 or more teeth. A fixed partial denture may be bonded or cemented on adjacent teeth or implants and cannot be removed by the patient; a removable overdenture, partial denture, or full denture may rest on remaining teeth, retained roots, implants, or completely on soft tissue for support and stability.

denture base

n: the gingiva-colored portion of the denture that is supported by the underlying soft tissue and holds the denture teeth

denture base material

n: the substance used to make the gingival (pink) portion of a removable plate or frame that supports artificial teeth.

denture border

n: (1) the periphery of the denture base at the point where the polished surface and the intaglio surface meet; (2) the facial, lingual, and posterior periphery of a denture base.

denture characterization

n: alteration of the texture and color of the denture base and teeth to create a more natural appearance.

denture curing

v: the procedure used to polymerize and harden the acrylic materials that form a denture.

denture design

n: the intended outline form used when fabricating a removable dental prosthesis for the purpose of replacing natural teeth with artificial teeth in a way that meets the clinician’s and patient’s expectations regarding function and aesthetics.

denture esthetics

n: the appearance of a dental prosthesis worn by the patient. The goal is a prosthesis that is proper and attractive for the patient.

denture flange

n: the portion of the denture base that extends into the soft tissue vestibule. It runs from the cervical ends of the prosthetic teeth to the edge of the denture’s border.

denture foundation

n: the soft tissue oral structures that support a dental prosthesis that replaces missing natural teeth with artificial teeth.

denture foundation area

n: the surfaces of the oral soft tissue used to support a dental prosthesis that replaces missing natural teeth with artificial teeth.

denture occlusal surface

n: the designated chewing portion of a dental prosthesis with artificial teeth that makes contact with the opposing dentition.

denture prognosis

n: an attempt by a clinician or laboratory technician to predict the success of a denture before starting the therapy.

denture prosthetics

n: the science of replacing natural teeth in a complete arch with an artificial substitute that is both functional and cosmetically pleasing.

denture resin packing

n: the placement of a denture base material with pressure into a mold positioned in the refractory flask.

denture retention

n: a measure of a denture’s resistance to movement away from its supporting soft tissue base. See also denture stability.

denture service

n: the clinical practices provided in the diagnosis, assembly, and maintenance of dentures.

denture space

n: (1) the three-dimensional area of the mouth that is or may be occupied by maxillary and/ or mandibular denture(s); (2) the space once occupied by teeth, alveolar bone, and surrounding soft and hard tissues but is now available for a complete or partial denture.

denture stability

n: (1) a measure of the resistance of a denture to lateral (horizontal) movement on its tissue foundation; (2) a characteristic of a denture that permits it to remain firmly seated in relation to its soft tissue foundation and/or abutment teeth.

denture supporting structures

n: the remaining alveolar ridges or teeth that serve as foundational support for a removable partial or full denture.


n: removal or loss of the protective oxide layer of a metal that creates a more reactive surface.


n: any device that alters reflexive proprioceptive behavior during mandibular closure.


n: the loss of surface epithelial cells through the process of exfoliation.

determinants of mandibular movement

n: the anatomic and physiologic factors that determine the envelope of function. These include the dental structures, occlusion, temporomandibular joint apparatus, and neurosensory function.


n: distraction (downward movement) of the mandibular condyle.

developmental dysmorphia

n: anomalous growth related to or induced by interference from neighboring structures.

developmental dysplasia

n: an abnormal growth pattern at the cellular or organ level.

developmental hyperplasia

n: excessive growth of tissue or organ system.

developmental hypoplasia

n: less than normal growth of tissue or organ system.


v: removal of investing material to retrieve a casting or prosthesis.


n: an apparatus developed by the application of principles or ideas to secure a specific outcome or function.


n: the process by which glassy substances change their structure to crystalline solids. This phenomenon may occur partially in dental ceramics if a ceramic restoration is fired too often, and it is typically associated with an opacified appearance.


v: to identify or define a disease or unwanted pathological condition by study of and deliberation on the signs and symptoms the patient presents with.


n: (1) the art and science of identifying and differentiating abnormalities from health and discerning the probable causes; (2) the identification and description of the nature, location, and basis of a disease or condition.


adj: relating to or used in determining the nature of a disease or condition.

diagnostic cast

n: a static replica of a part or parts of the oral cavity and/or facial structures for the purpose of diagnosis and development of a treatment plan. See also cast.

diagnostic denture

n: a provisional removable dental prosthesis constructed for the purposes of functional and esthetic evaluation of the intended final therapy.

diagnostic occlusal prosthesis

n: a removable dental appliance, typically constructed from acrylic resin, that provides an occlusal overlay on the teeth. It is designed to evaluate a patient’s response to proposed comprehensive restorative procedures.

diagnostic radiation

n: the radiation a patient receives when radiographs are used for the purpose of determining the nature of a disease.

diagnostic tooth preparation

n: alterations performed on a dental cast before actual tooth preparation so the proposed tooth preparation can be evaluated and changed as needed before actually cutting the intended tooth.

diagnostic waxing

n: waxing of proposed restorative forms on dental casts for the evaluation and planning of intended restorations.

diarthrodial joint

n: a freely moving joint.


n: a specific articulation permitting more or less free movement; a bone articulation that permits free movement in a joint. Structurally, it is a synovial joint.


n: treatment using heat generation through tissue resistance to high-frequency electromagnetic current.


adj: a canal placed in denture teeth to provide mechanical retention of the denture teeth in a denture base of a chemically different material.

differential diagnosis

n: the distinguishing of a disease or pathological condition from others presenting similar signs.


n: (1) a splitting apart; (2) abnormalities in the angulation or shape of a formed tooth’s root or crown as the result of injury during the tooth’s development stage.

dimensional stability

n: the capacity of a material or substance to maintain its shape and size when subjected to various environmental changes, including moisture, temperature, and stress.

dimensions of color

n: the three-dimensional system describing color developed by Munsell. The dimensions are (1) hue (color family), (2) value (lightness/ darkness), and (3) chroma (strength).

direct bone impression

n: a negative likeness of bone produced through a flap reflection and direct impression. Usually, it is the initial part of the 2-stage surgical impression technique for subperiosteal implant construction.

direct retainer

n: the unit of a removable dental prosthesis that engages an abutment tooth to resist movement of the prosthesis away from the basal seats. The unit consists of an extracoronal clasp assembly or intracoronal retainer, e.g., precision attachment.

direct retention

n: displacement resistance of a partial removable prosthesis away from the basal seats by the use of extracoronal or intracoronal direct retainers.


n: the separation of 2 articulated structures at their joint parts.


n: a thin, flat, circular object or plate. See also disc, articular.

disc, articular

n: fibrous connective tissue that separates temporomandibular joint cavity into 2 compartments. Also called the meniscus. Fibrous connective tissue between 2 bony structures to reduce abrasion and friction located in a joint cavity, also called the meniscus.


n: removal of the intra-articular disk. The word is a compound Greek word, formed from the words disk and extomy, which means excision/removal. As a compound word, it means removal of a disk. It typically refers to removing the meniscus or intra-articular cartilage in a joint.


n: a tablet or solution that when rinsed in the oral cavity visibly stains dental plaque colonies. It is often used as an adjunct in oral hygiene instructions because it helps the patient identify the areas of plaque accumulation that can potentially induce hard and soft tissue damage.


n: typically a liquid agent that is applied to surfaces of objects for the purpose of destroying or inhibiting the disease-producing or other harmful effects of microorganisms. Normally it does not destroy bacterial spores.


n: a component of artificial prosthesis that allows movement between 2 or more parts.


n: regarding the temporomandibular joint, the avascular intra-articular tissue that separates the temporomandibular joint into 2 compartments. The avascular intra-articular tissue separating two bone surfaces allows for movement of the joint; also spelled disc.

disk degeneration

n: progressive degenerative changes in the temporomandibular joint articular disk; the breakdown of the joint articular disk through degenerative disease.

disk derangement

n: a misalignment of the articular disk between the condyle, fossa, and/or the bony eminence that often results in pain, swelling, and/or difficulty with mastication.

disk detachment

n: a separation of the disk from its capsule, ligament, or bony surface.

disk displacement with reduction

n: disk dislodgment where the temporomandibular joint disk has shifted in an anterior-medial direction when at rest but returns to its proper position with mandibular movement. It frequently has an associated clicking sound.

disk displacement without reduction

n: disk dislodgment where the temporomandibular joint disk has shifted in an anterior-medial direction when at rest but does not return to its proper position with mandibular movement.

disk interference

n: restriction of mandibular movement because of pathology or dysfunction of the disk; a dysfunction of the normal articular disc movement that often results in pain and normal mandibular movement.

disk locking

n: a dysfunction of the disk’s normal position and/or function in the temporomandibular joint in which it cannot return to normal position or function.

disk perforation

n: a bounded hole or tear in the center of the temporomandibular joint’s articular disk that is the result of deterioration associated with habitual increased compressive forces. The opening allows for communication between the superior and inferior joint spaces. The attachment associated with the capsule, ligaments, or bone is not altered.

disk prolapse

n: rotation of the temporomandibular disk downward and forward on the face of the condyle eminence.

disk space

n: the space that is typically occupied by the intra-articular disk between the mandibular condyle and the articular fossa that is represented on a temporomandibular joint radiograph as a radiolucency.

disk thinning

n: reduced thickness of the intra-articular disk as a result of an autoimmune degenerative process, chronic pressure during function, or the combination of both.

dislocated fracture

n: a break of a bone associated with displacement of the fractured segment from its intended joint.


n: pathologic displacement of a bone out of the natural anatomic boundaries of its fossae. It is frequently associated with pain, reduced range of motion of the affected bone, and ligament or cartilage pathosis. It may be chronic or recurrent.


v: progressive separation of occluding teeth from maximum intercuspation position during jaw movements due to tooth guidance, occlusal interferences, or occlusal adjustment


n: separation of occluding teeth from maximum intercuspation position during eccentric movements.

displacement of the mandible

n: a position or movement of the mandible beyond its normal anatomic boundaries.


adj: in a sagittal plane along the midface; a location, movement, or surface that is located toward the retromolar pads compared with the central incisors.

distal extension partial denture

n: The boundaries of a removable partial denture distal to the terminal tooth. A removable partial denture prosthesis that does not have a natural abutment tooth at the distal aspect either on one or both sides. The distal tooth at the distal aspect of the arch is an artificial tooth provided by the prosthesis.

distal wedge

n: a periodontal surgical intervention at the distal area of a terminal tooth in an arch. The goal is to remove excessive tissue, reduce periodontal pocket depth, and facilitate oral hygiene in the area.


n: the clinical situation where at maximum intercuspation the mandibular teeth have a distal relationship to the maxillary teeth as in an Angle’s Class II occlusion.


n: a deviation or positioning toward the distal. Any deviation along the median sagittal plane directed from the incisors to the retromolar pads.

distraction of the condyle

n: dislocation of the condyle in an inferior direction; the clinical condition where the condyle is inferiorly displaced and typically associated with pain.

distraction osteogenesis

n: a bone augmentation procedure where a portion of the jaw is sectioned by osteotomy and progressively displaced by a mechanical device that is attached to the separated bone segment and the original bone. The displacement is gradual and controlled and it is anticipated that newly formed bone will occupy the space between the distracted bone segment and the original bone.

disuse atrophy

n: decrease in the size of a cell, tissue, organ, or body part as a result of nonuse. The word atrophy is a Greek word comprised of 2 segments: the a means less and trophy means food or feeding. As a combined word atrophy means a regression of any tissue or organ or part of the body due to lack of nutrition. “Disuse” is lack of utilization or inactivity. When these 2 words are combined, “disuse atrophy” defines a situation where part of a cell, a cell itself, a tissue, an organ, or a part of the body is hypofunctioning or not utilized, which leads to a decrease in the size, vascularity, efficacy, and overall functionality of the cell, tissue, organ, or body part.

divergence angle

n: the sum of the tapered angles for the divergent opposing walls of a tooth preparation.

documentation, periodontal

n: diagnostic, radiographic, and therapeutic dental charting records of a patient’s soft and hard tissue support for the teeth.

Dolder bar

n: eponym for one of several bar attachments that join teeth or roots together and provide abutment support for a removable partial dental prosthesis. The bar is straight and has a pear or ovoid shape. A retentive clip fits over the bar and allows for some rotational movement about the bar. The clip derives its retention by friction when placed on the bar. The bar comes in assorted sizes.

donor site

n: the part of the body from which an autogenous graft is obtained.

double wire clasp

n: a wire circumferential clasp with back-to-back retentive arms.

dowel pin

n: a metal indexing pin used in stone casts that permits removal of the die section and its precise replacement in the original position.


n: the inferior or lower side of a refractory denture flask. It fits precisely with the upper (cope) side of the denture flask.


n: for a crown or restorative preparation, it is the taper or convergence of the opposing walls.


n: (1) the solid scum produced from oxides, impurities, or waste materials on the surface of a metal when melted; (2) waste matter; refuse.

duplicate denture

n: a second denture that is identical in all aspects to the in-use or functioning denture.


n: an instrument that measures the hardness of a material.


n: an abnormal and unpleasant sensation.


n: to not function properly or normally as a cell or within an organ. In dentistry, a dysfunction means any abnormality between the physical nature of the teeth, bones, or joints within the oral cavity and their function as mediated through muscles or nerves affecting the oral cavity and causing abnormal functioning.


n: any change or distortion in the sense of taste.


n: a change in or difficulty in performing voluntary movements like walking, bending, or lifting.


n: abnormal articulation or difficulty in articulating due to defects in organs associated with speech and not due to neurologic disorders.


n: difficulty in chewing (mastication).


n: imperfect ossification resulting in abnormal bone development.


n: difficulty in or lack of complete swallowing, which slows the movement of food from the mouth into the stomach.


n: disorder of the voice caused by the inability to make voice sounds through the vocal cords resulting in hoarseness or difficulty in speaking.


n: the abnormal development of cells, tissue, or organs. In dentistry, various dysplasias have been observed that are associated with abnormal dentin (dentinal dysplasia), abnormal ectoderm (ectodermal dysplasia), or abnormal periapical bone (periapical cemental dysplasia) affecting root formation (dentinal d); tooth, sweat gland, and nose bridge development (ectodermal d); and the periapical bone of vital teeth causing the center to become opaque due to a cementoma or odonogenic tumor.


n: a neurologic disorder resulting in sustained muscle contraction that affects movement causing twisting and repetitive motions of the tongue, jaw, eyes, neck, and sometimes the entire body.

dystrophy, periodontal

n: degeneration of the periodontium caused by changes in bone mechanics, circulation, etc. that results in abnormal physiological function.


Early-onset periodontitis

n: see under periodontitis.


n: the extravasation and collection of blood into the subcutaneous tissues, which appears as a yellow to bluish mark on the mucous membrane or skin. Injury to or fragility of the underlying blood vessels may be the cause.


adj: occurring in an abnormal position, away from the normal location, in an unusual manner, or situated in an unusual place or form.

ectopic eruption

n: eruption of a tooth outside the expected or usual location or in displaced position.


n: a condition of abnormally large fluid volume or abnormal swelling subsequent to the collection of fluid in a tissue or between the body’s cells.


v: the process by which all teeth are removed.


adj: to be edentulous; to be without natural teeth.


adj: not having teeth, devoid of teeth.

elastomeric impression material

n: a polymer that has weak intermolecular forces with characteristics of viscosity and elasticity; compared with other materials it has a low Young’s modulus and high failure strain. The term originates from elastic polymer, which is also known as rubber.


n: (1) a solid electric conductor that allows for current to enter or leave a medium or electrolytic cell; (2) a component of an X-ray tube that electrons are attracted to or released from. The anode is the positive electrode and the cathode is the negative electrode.

electromyographic biofeedback

n: a process employing instruments to assist patients in controlling their muscle tension that are normally under automatic control.


n: the graphic display and record of the electrical potential of muscle(s).

electron accelerator

n: an instrument designed to increase the energy level of electrons in radiation therapeutics.

electron beam therapy

n: the use of high-energy electrons for therapy, such as with a betatron.


v: the process of coating an object’s surface with a thin layer of metal by the process of electrolysis.


v: removing a layer of metal by electrolysis, thus producing a bright surface on the material.


n: using a metal instrument to apply high-frequency electrical current at localized sites to produce tissue division.

elevator muscle

n: one of the contracting muscles that raises or closes the lower jaw.


n: a foreign material, such as a blood clot or air, that migrates in the bloodstream leading to an obstruction of a blood vessel.


n: the manner in which people position and use their mouth (teeth, lips, and tongue) when playing a wind instrument.


n: (1) the space created when proximal surfaces are positioned away from each other; (2) in dentistry, the space set up by the diverging mesial or distal surfaces of 2 teeth that are adjacent to each other.

emergence angle

n: the incline created by a dental implant’s transitional shape as determined by the correlation of the long axis of the implant body to the implant abutment or prosthesis.

emergence profile

n: the axial contour of a crown on a tooth or a dental implant abutment as it correlates to the adjacent soft tissues.


n: the projecting prominent part of an object, especially on the surface of a bone.


n: (1) a pathological swelling caused by accumulation of air or gas in tissue spaces. In the oral cavity and facial regions, it may be initiated by the unintentional introduction of air into a tooth socket or gingival crevice with an air syringe, an air-driven dental handpiece, a continuous positive airway pressure or bilevel positive airway pressure machine, coughing, or nose blowing; (2) a chronic respiratory disease where there is a perpetual dilation of the respiratory alveoli in the lung, causing a reduction in lung function and frequently breathlessness.

empty mouth movement

n: voluntary or involuntary changes of the mandible’s position when the jaws are not engaged in incising or chewing.


n: in dentistry, the hard, thin, translucent layer of calcified material that covers the coronal portion of a tooth. It protects the dentin located directly underneath it and is known to be the hardest substance in the body.

enamel pearl

n: a developmental abnormality that results in a small localized mass of enamel formed apical to a tooth’s cementoenamel junction. It is frequently found in the bifurcation of molar teeth.

enamel projection

n: an apical extension of a tooth’s enamel that is often found at the root furcation.


n: see occlusal reshaping.


n: a joint in which the rounded (ball-like) head of one bone fits into the socket form of another bone (eg, hip joint).


n: exudative and proliferative inflammation of the endocardial surface of the heart. Infective endocarditis is a bacterial infection of the endocardial surface of the heart, most often involving the heart valves. Previously it was categorized as acute, subacute, or chronic bacterial endocarditis but now it is categorized by the offending microorganism (ie, streptococcal infective endocarditis).

endodontic-endosseous implant

n: see under implant, oral.

endodontic endosteal dental implant

n: a pin that is intended to perform as an implant; it may be smooth or threaded and is placed into the root canal space of an endodontically treated tooth with an extension into periapical bone. The intent is to stabilize a mobile tooth; also known as an endodontic stabilizer.

endodontic pin

n: a metal pin that is intentionally placed through the apex of a mobile tooth and into the surrounding apical bone for stabilization.


n: an instrument with a flexible or rigid tube used for examining the interior of a canal or hollow space.

endosseous blade implant

n: see blade endosteal dental implant.

endosseous implant

n: see endosteal dental implant and implant, oral.

endosteal dental implant

n: a manmade device positioned into the alveolar and/or basal bone of the mandible or maxilla that transects a cortical plate. It is made up of an endosteal dental implant body that provides anchorage when positioned and integrated within the bone and the endosteal dental implant abutment that retains the prosthesis. Multiple adjectives are used to describe the endosteal dental implant. It can be described by its shape (e.g., cylinder, screw, conical, blade, or basket) or can refer to the materials from which the implant is constructed (e.g., titanium, titanium alloy, or ceramic).

endosteal dental implant

n: the part of the implant that passes through the oral mucosa and allows for the connection between the body of the implant and the restorative prosthesis. The abutment is often referred to as an implant element. It attaches to the body of the dental implant with screws, thread/screw interfacing, and a male/ female Morse taper fit. The purpose of an abutment is to support and/or retain a fixed or removable dental prosthesis or a maxillofacial prosthesis. The dental implant abutment may be for interim (provisional) or definitive use. Descriptions of the dental implant abutment are based on number of pieces (1 piece joined to implant body, 2 piece, or 3 piece); fabrication technique (stock, stock-adjusted, or custom); angulation (straight or angled), and material that it is made of (titanium, titanium alloy, gold, or ceramic).

endosteal dental implant abutment element

n: a dental implant component used to attach the dental implant body to the prosthesis or the prosthetic attachment.


n: a heat-stable, lipid polysaccharide complex found in the cell wall of many microorganisms (mostly gram negative) known to contribute to periodontitis. It can be cytotoxic or pyogenic and has been shown to promote inflammation. In contrast to an exotoxin, an endotoxin remains part of the microorganism cell wall and is not released into the environment.


n: denotes a concentration of mature compact (cortical) bone within the cancellous bone (spongiosa) and can be referred to as condensing osteitis. This benign lesion may be located anywhere in the skeleton but has a predilection for the long bones and pelvis. It is probably congenital in nature and suggests failure of resorption during endochondral ossification.

entrance port

n: the area on the surface of a patient where a radiation beam is incident.


v: to remove an organ or lesion in its entirety without rupture. Term often used to describe the removal of a benign odontogenic cyst from the jaws.


n: a catecholamine neurohormone produced by the adrenal medulla and secreted into the blood supply, whereupon it is circulated throughout the body and may stimulate receptors that initiate sympathomimetic effects; used in local anesthetic solutions for its activation of alpha receptors, which induces vasoconstriction.

epithelial cuff

n: a term that describes the intimate relationship between the gingival mucosa and the dental implant. The term suggests a lack of true biochemical connection or attachment between the implant and mucosa.

epithelialization (epithelization)

n: (1) the growth of epithelium over connective tissue during the healing process; (2) the process, either pathologic or part of normal healing, whereby an area of the oral cavity is covered by or converted to epithelium.


n: anatomy term used to describe the surface layer or lining of an organ. In the mouth it is used to describe the mucosal tissue serving as the lining of the intraoral surfaces.

epithelium, oral

n: the tissue serving as the lining of the intraoral surfaces. The junctional form is nonkeratinized, is single or multiple layered, and adheres to the tooth surface at the base of the gingival crevice. The epithelium in the oral cavity is either keratinized or nonkeratinized depending on its location.

eposteal dental implant

n: a dental implant that obtains its principal support through setting on top of the edentulous areas of the alveolar bone; Supplementary retaining screws that enter directly into the bone for the purposes of securing this implant framework to the alveolar bone are referred to as an endosteal dental implant component. If the eposteal framework should become submerged and covered by the alveolar bone, then it may be described as having become an endosteal dental implant; an eposteal dental implant’s support system is also known as the implant frame, implant framework, or implant substructure.

epoxy resin

n: a strong, yet flexible, chemically resistant, dimensionally constant resin of epoxy polymers; frequently used as a denture base material in dentistry.

epoxy resin die

n: a reproduction or model produced with epoxy resin.


n: a nonspecific word for any inflammatory cellular proliferation or a tumorlike growth or lump of the gingiva.

epulis fissuratum

n: overgrowth of intraoral tissue as the result of chronic irritation; an overgrowth of intraoral tissue associated with persistent irritation such as that caused by the overextended flange of a denture.

equalization of pressure

n: the act of evenly distributing a load.


v: to bring or to place in balance or equilibrium.


n: the action or process of creating a state of balance or equilibrium. See mandibular equilibration or equilibration, occlusal.

equilibration, occlusal

n: (1) the process of bringing patients’ teeth when closed into a state of balance by selectively grinding premature or excessive opposing tooth contacts; (2) the equalization of occlusal stress by modifying the chewing surfaces of a tooth or teeth that results in the formation of proper occlusal contacts or harmonizing cuspal relations. See also occlusal adjustment.


n: the chemical dissolution or eroding of enamel and dentin that results in a cavity with a hard, smooth base. It is unrelated and discrete from caries.

eruption, dental

n: the appearance of a tooth in the oral cavity.

  • active eruption: the progression of a tooth moving from its origination position to its functional position.
  • passive eruption: when a tooth becomes exposed because of the secondary apical migration of the gingiva.

erythroplasia (erythroplakia)

n: a red, papular, or macular lesion that is frequently ulcerated and found on a mucous membrane. It is considered to be precancerous.


n: a scab caused by a burn, by cauterization, or through application of a corrosive substance.


n: concerning the study of attractiveness and the awareness of beauty.

esthetic reshaping

n: modification of biological surfaces, such as the teeth or face, to enhance beauty.


n: (1) the segment of philosophy concerned with beauty; (2) in dentistry, the discipline related to the pleasing appearance of a dental restoration as accomplished through its shape, fit, and color. It includes the subjective and objective aspects fundamental to the attractiveness of a prosthetic restoration.


n: a broad term for naturally occurring steroid hormones composed of an estrane nucleus (eg, estrone, estradiol, estriol). The ovaries, placenta, and testis secrete these estrane-based hormones that induce protein anabolic actions and have a positive effect on nitrogen balance. It controls the growth and maintenance of female auxiliary sex organs and secondary sex characteristics and is implicated in hormonal-, pubertal-, and menopausal-associated gingivitis.


n: a chemical or compound that can used to etch a surface.

ethylene oxide

n: a bactericidal agent that is a toxic, flammable, colorless gas or liquid frequently used for sterilizing or disinfecting medical instruments.


n: elimination of the viscera or contents of a cavity; extraction; removed, usually as an unexpected nature.


n: see avulsion.


n: an increase in the severity of the signs or symptoms of a disease.


n: (1) a movement away from and back to the mean position or alignment; also, the distance navigated; (2) in dentistry, the movement transpiring when the mandible moves from the position of maximum intercuspation.


adj: any movement away from the maximal intercuspation between the maxillary and mandibular teeth

excursive movement

n: movement occurring when the mandible and its associated teeth move away from the maximum intercuspation position with the maxillary teeth


n: organ removal.


n: (1) the sloughing of a previously attached matter or tissue from the body, for example, the sloughing of the oldest nonvital epithelial cells from the skin’s outermost surface; (2) in dentistry, the physiological shedding of the primary teeth or the loss of implanted materials.


adj: due to external source or cause; not developing from within the organism.


adj: emergent outward; proliferation on the outside or surface of an organ.


n: a benign, bony growth jutting outward from the normal physiological surface of a bone.


n: a toxic substance or matter formed by a bacterial species that is released to the surrounding environment.


n: (1) a surgical or dental procedure that uncovers or lays open a desired specific area or object; (2) in radiology, based on the ability to cause ionization it is a measure of the roentgen rays or gamma radiation. See also roentgen ray.

external oblique ridge

n: a smooth edge or ridge on the buccal surface of the body of the mandible that ranges from the anterior border of the ramus, with lessening prominence, downward and forward to the region of the mental foramen. This edge or ridge remains unchanged in size and direction for the most part throughout life. It is where the buccinator muscle attaches and affords a consistent landmark for the construction of dentures and subperiosteal implants.


v: (1) to deliberately pull up or out; (2) to completely annihilate or destroy; (3) to surgically remove.


n: the complete surgical elimination or removal of a tissue or organ.

extracapsular ankyloses

n: immobility and consolidation of a joint due to rigidity of any structure external to the joint capsule resulting from disease, injury, or surgery.

extracapsular disorder

n: pain and dysfunction associated with the masticatory apparatus, which is caused by etiologic factors located outside the temporomandibular joint capsule.


adj: outside the cortical plate of the bone or bone cortex.

extraoral tracing

n: a recording of mandibular movements made with a stylus on a recording plate that extends outside the oral cavity. A tracing made outside the oral cavity.


adj: originating from or positioned without; outside.

extrinsic coloring

n: shading from without; color applied to the exterior surface of a prosthesis.


n: (1) the overeruption or movement of teeth outside the desired occlusal plane that may be accompanied by a similar movement of their supporting tissues; (2) squeezing out of material through the application of pressure, such as denture acrylic escaping from the invested flask as hydraulic pressure is applied to it.


n: a fluid produced as a result of injury to tissue and/or to a blood vessel. The secreted material can be made of serum, fibrin, white blood cells, and/ or red blood cells that escape from blood vessels into a superficial lesion or area of inflammation. The content of the fluid is dependent upon the in situ environment. Serum can be predominant if the exudate is fabricated by the contraction of a fibrin plug in the damaged space that releases serum into the area; or the exudate composition could be primarily made of polymorphonuclear leukocytes as in the case of pus formation at an injury site.



n: a caliper-like instrument used in conjunction with the attached facebow fork to transfer the correct position of the maxillary cast on the articulator such that it replicates the position of the maxillary dental arch to the temporomandibular joints.

facebow fork

n: component attached to the facebow that transfers the maxillary arch position to the facebow, thus orienting the occlusal table of the dentition to the center of rotation of the condylar joints of the mandible to a selected anterior point on the face (eg, the infraorbital fossa).

facebow record

n: the registration obtained through the use of a facebow and facebow fork using 3 points of orientation (center of rotation of both condylar joints and an arbitrary point on the face) that have been locked into place in relation to each other.

facebow transfer

v: the process of conveying the recorded facebow 3-deminsional correlation of the maxillary dental arch and additional anatomic orientation point(s) to the articulator.

face form

n: the outline shape of the face from the frontal view, designated by shape as square, tapering, ovoid, or a blend of these shapes. Facial shape may be used to choose tooth shapes for a dental restoration to be in harmony with the facial form, creating a more natural and pleasing esthetic effect.


n: a small, flat visible surface on any hard body created by function. Specifically, a facet on a tooth may indicate wear, usually on the occlusal or incisal surface of a tooth, which has been caused by wearing against an opposing tooth. The observation of facets of wear on teeth can be clues to parafunctional habits or disharmony of the occlusion of opposing teeth due to malocclusion.

facial augmentation implant prosthesis

n: a maxillofacial prosthetic device created out of a material that is biocompatible and may be generally implanted by being laid over a bony area beneath the skin in order to recontour portions of the facial skin to create the desired contours. It may be premade, the prosthetic device for facial augmentation is more frequently custom-made because of the unique nature of most facial defects. Also called a facial implant.

facial form

n: anterior view of the facial outline.

facial prosthesis

n: a maxillofacial prosthetic device that restores a portion of the face that is congenitally absent or altered due to surgery or trauma. Also called an extraoral prosthesis or prosthetic dressing.

facial prosthetic adhesive

n: a substance used to retain a facial prosthesis in its proper position.


n: a veneer of a restoration on a natural tooth or prosthetic device to alter, duplicate, or improve upon the appearance of a natural tooth.


adj: a condition that occurs in members of a family.


n: disintegration of a material related to cyclical, repeated, or applied loads that do not exceed the yield limit. Disintegration sometimes begins as minute cracks and can be followed by a more complete fracture, tear, or rupture. Also known as brittle failure or fracture.


v: to puncture or perforate with one or several openings.


n: a hole or opening in a body part, for example, a hole in alveolar bone or the soft tissue that covers the root of a tooth.


n: the most apical area of preparation around the base of a tooth beyond any core material or post to provide retention and resistance form for a crown. The ferrule is to be on sound tooth structure and ideally 2 mm or more in height.


n: shaping of denture base material to reproduce the natural contours of gingival tissue.

festoon, gingival

adj: the rounding and enlargement of the marginal gingiva over the roots of the teeth.


n: foul or unpleasant breath odor. See also halitosis.


n: a filament or strandlike structure.

  • collagen fiber: elastic, soft, white fibers containing protein collagen fibril bundles that are the most representative component of all connective tissue.
  • muscle fiber: skeletal or heart muscle cells.
  • nerve fiber: the slim axonal process of a nerve cell.
  • periodontal fiber: typically a collection of collagenous or elastic connective tissue.
  • reticular fiber: immature connective tissue fibers.


n: the principal connective tissue cell; a flattened, irregularly branched cell with a large, oval nucleus that functions in the production and remodeling of extracellular matrix.

fibroblast growth factor

n: a lineage of growth factors that are mitogenic for fibroblasts and mesoderm- derived cells.


n: fibrous connective tissue that is a benign neoplasm; peripheral.

  • ossifying fibroma: a fibroma, normally of the gingiva, presenting with areas of calcification or ossification.

fibro-osseous (fibro-osteal) integrated implant

n: see under implant, oral.


n: a subsurface collagenous soft tissue replacement that occurs as a result of chronic inflammation. The tissue appears and feels thick and dense. Fibrosis may occur as a result of chronic inflammation around dental implants that support prosthetic crowns. The tissue becomes thick and enlarges with collagen deposition in the surrounding gingival tissue. There is usually no bleeding on probing of the surrounding sulcus. The collagenous deposition may occur interproximally at supporting implants that fill the embrasure space to mimic interdental papillae.

fibrous adhesion

n: a fibrous band or structure by which parts not normally connected adhere to each other.

fibrous ankylosis

n: decreased movement of a joint due to proliferation of fibrous tissue.

fibrous integration

n: the existence of a sheet of interfering fibrous connective tissue membrane found between a dental implant body and the contiguous bone.

filiform papilla

n: see under papilla.

final impression

n: the definitive impression that embodies the completion of the registration of the surface for construction of the prosthetic replacement.


n: to put a definitive covering or surface on; the enhancement of a form before polishing.

finish junction

n: the marginal adaptation of tooth and restoration.

finish line

n: (1) a delineation line determined by 2 points; (2) the marginal extension of a tooth preparation; (3) the prearranged seam of dissimilar materials; (4) the end portion of the prepared tooth.


n: (1) a delineation line determined by 2 points; (2) the marginal extension of a tooth preparation; (3) the prearranged seam of dissimilar materials; (4) the end portion of the prepared tooth.


n: the method of porcelain fusion, in dentistry, purposely to fabricate porcelain restorations.

first-stage dental implant surgery

n: the first surgical procedure in dental implant placement. For eposteal (subperiosteal) dental implants, the initial surgical procedure consists of full reflection of the oral mucosa, followed by a bone impression, plus an interocclusal record that will be used in fabricating the implant body. Suturing the soft tissue together completes the first stage. (2) For an endosteal implant, the first-stage surgery refers to the reflection of the oral mucosa, preparation of the osteotomy (implantation site), and placement of the dental implant body. Suturing the soft tissue together completes the first stage.


n: any cleft or grove, naturally present; a cleft or profound trough on the surface of a tooth, usually due to defective fusion of neighboring lobes of enamel.


n: a pathologic or atypical passage that is the result of poor healing; an unintended or unwanted pathway between differing internal structures or one that connects an internal structure to the (external) surface of a body; usually named according to the body parts it connects.

  • oroantral fistula: An atypical communication between the maxillary sinus and the oral cavity.
  • orofacial fistula: An atypical communication between the cutaneous surface of the face and the oral cavity.
  • oronasal fistula: An atypical communication between the nasal cavity and the oral cavity.


adj: firmly placed; immovable and stable in one place, does not move.

fixed dental prosthesis

n: a prosthetic dental device that is firmly attached to natural teeth and/or the abutment of a dental implant. It provides the prime support for the device. This prosthesis is not intended to be removed by the patient.

fixed dental prosthesis retainer

n: the portion of a fixed dental device that joins the abutment(s) to the other parts of the device.

fixed partial denture

n: see fixed dental prosthesis.

fixed prosthodontics

n: subdivision of prosthodontics that is concerned with the replacement of teeth with dental implants and/or replacement of tooth crowns with restorations fixed in place (nonremovable).


n: an endosteal dental implant. Term coined to define an endosteal dental implant—root form, blade, ramus frame—that are embedded and integrated or fixed in the bone for stabilization of the superstructured prosthetics.


n: a rim used for strength, for directing or connecting to another segment of an object. The portion of denture material protruding into the buccal, lingual, or labial tissue area of a denture.

flange contour

n: the design of the extension of a denture shape or form of a protuberance or extension of a denture tissue surface.


n: a loosened portion of tissue usually intestinally separated from the adjacent tissues except at the base.


n: a container used in investing procedures, usually a metal case or tube.

flask closure

n: a process by which 2 halves, or parts, of a flask are brought together.


v: before the final molding preparation of the denture, this process is the act of investing the wax replica of the anticipated form into a flask.


n: a prosthesis that is usually considered to be temporary in design. It traditionally has one tooth attached to an acrylic base typically without clasps, although wrought wire clasps may used for additional retention.

flowing composite resin

n: compared with a conventional composite resin, this type of resin has less filler and less viscosity but improved wettability.

foliate papilla

n: see under papilla.


n: a natural opening or passageway, specifically into or through a bone.

foreign-body reaction

n: in gingiva or mucosa around a prosthesis this may appear as acute or chronic inflammation and can generate red, red/white or tattoos, or pus-producing lesions.

forward protrusion

n: an anterior or frontward protuberance of the centric position.


n: a hallow anatomic pit, concavity, depression, groove, or depression.

foveae palatinae

n: two depressions found in the posterior portion of the palatal mucosa, one on each side of the midline, either at or in close proximity to the place where the soft and hard palates meet.


v: to result in a fracture; to split up, rupture, or tear.

fracture strength

n: durability or strength of a specimen that is a function of its original configuration.


n: (1) a structural support used to sustain another object or objects; (2) the metal or ceramic skeletal part of a dental prosthesis about which are attached the remaining segments of the prosthesis.

free gingival

adj: the aspect of the gingival tissue surrounding the tooth and not directly attached to the surface of the tooth.


n: a vibration that can be observed visibly or is perceivable on palpation; in dentistry, the movement of a tooth that is felt when the teeth come into contact.

frenectomy (frenulectomy, frenotomy)

n: surgical detachment and/or excision of a frenulum from its attachment into the mucoperiosteal covering of the alveolar process.


n: a small strip or fold of integument or mucous membrane that restricts the movements of an adjacent structure.

friction retained pin

n: a metal dowel placed into a hole drilled by the clinician in the dentin to enhance retention of a restoration; it is retained exclusively by the elasticity of the tooth’s dentin.

fructosamine blood test

n: a blood test that indicates the average level of blood glucose control over the 2-3 weeks prior to obtaining the blood sample. It is used as a marker to evaluate a patient’s diabetes mellitus. Higher levels of serum fructosamine correlate with sustained hyperglycemia for the 2-3 weeks prior to having the test performed. For patients without diabetes mellitus fructosamine serum levels range 175-280 mmol/L. For patients with controlled diabetes mellitus the serum fructosamine levels range is 210-421 mmol/L.

full-denture prosthetics

n: (1) substitution of the natural teeth in the arch and the related parts by manmade alternatives, including but not limited to acrylics, alloys, and porcelain; (2) the discipline rebuilding an edentulous mouth.

full-thickness graft

n: transfer of skin or gingival epithelium in full thickness with little or no attached subcutaneous tissue.

fully adjustable articulator

n: an articulator that permits simulation and duplication of the 3-dimensional movements of recorded mandibular motion. See also Class IV articulator.

fully adjustable gnathologic articulator

n: an articulator that permits simulation and replication of the 3-dimensional mandibular movements with the added benefit of providing documented timing of the mandibular motion; also called a Class IV articulator.

functional articulation

n: occlusal contact points on the maxillary and mandibular teeth during the process of chewing.

functional dislocation

n: displacement of the temporomandibular joint’s articular disk during function due to derangement of the disc-condyle complex.

functional jaw orthopedics

n: application of muscle forces to influence changes in jaw position and tooth alignment by removable appliances.

functional occlusal harmony

n: the highest degree of masticatory efficiency in all ranges of motion without functional strain or trauma.

functional occlusal splint

n: any device that works to control the plane and range of mandibular movement.

functional occlusion

n: position of the working contacts of the maxillary and mandibular teeth during chewing.

functional record

n: the recording of the envelope of motion of the mandible for measurement or duplication in a prosthetic device.

functionally generated path

n: the path of motion dictated and constrained by the morphology and position of the teeth, joint anatomy, and muscles of mastication.

fungiform papilla

n: see under papilla.


n: the area of root divergence in a multirooted tooth.


adj: a term to describe the morphology of certain types of bacteria, indicating a spindle or cigar shape; reflective in the genus Fusobacterium.


Galvanic stimulation

n: excitation of muscle fibers by applying mild electrical current.


n: induction of an electrical current between 2 materials with different electronegativities. This can produce nerve or muscle stimulations. (2) accelerated oxidization of a metal from an electrical interaction with a more noble metal in a corrosive electrolyte. The consequential current flow can create nerve stimulation, an electric shock-like experience, or a disagreeable taste.


adj: relating to the chin.

genial tubercles

n: bony projections at the midline on the lower lingual surface of the mandible to which the genioglossus muscle attaches above and the geniohyoid muscle below.


n: cosmetic surgery to improve the appearance of the chin (mandibular symphysis).

geographic tongue

(benign migratory glossitis) n: a chronic condition characterized by desquamation of the superficial epithelium of the dorsum of the tongue, which migrates continuously.


n: a disinfectant that kills germs, especially pathogenic microorganisms.


n: two teeth that are joined and have developed from the same tooth bud.


n: the connective tissue that surrounds the teeth, covers the jaws, and is covered by epithelium.


adj: relating to the gingiva. See also gingival crevice.

gingival abscess

n: a pus-producing infection of the gingiva where relative localization has occurred.

gingival crevice

n: the envelope formed between the gingival cuff and the tooth or implant, coronal to its epithelial attachment. Syn: gingival sulcus, periodontal pocket

gingival curettage

n: see under curettage.

gingival denture contour

n: portions of a prosthesis that mimic the soft tissue surrounding a tooth or teeth. Syn: pink porcelain, pink acrylic.

gingival disease

n: recognizable signs and symptoms of various disease states that are localized to the gingiva; also called gum disease or periodontal disease. Gingival disease can be caused by fungal, bacterial, or viral infections that arise from the dental plaque or oral cavity; diseases that affect the immune system (eg, AIDS, cancer); or diseases/conditions that can predispose one to bacterial growth in the gingiva, such as diabetes, menopause, use of drug therapies (eg, glucocorticoids, Dilantin, Procardia), or lifestyle (eg, smoking, poor oral hygiene habits). Common symptoms include swollen gingiva that bleed easily and may be accompanied by white, red, or ulcerative gingival lesions. Over time, the chronic infection that occurs between the teeth and gingiva can cause gingival displacement and bone deterioration resulting in loss of teeth.

gingival displacement

n: the movement or retraction of the marginal gingiva, the gingiva located at the buccal, labial, lingual, and palatal areas of the teeth, away from a tooth.

gingival embrasure

n: area of the gingiva, usually having a V shape in the maxilla and an inverted V shape in the mandible, that fills the space between adjacent teeth that lies cervical to the interproximal contact area.

gingival porcelain

n: porcelains (usually pink in color) used to blend the cervical portions of the gingival margins between the prosthetic and the oral cavity.

gingival retraction

n: see gingival displacement.


n: gingival inflammation.


n: A resective gingival surgical procedure performed to reshape and recontour of the gingiva.


n: former nomenclature for desquamative gingivitis.


n: Inflammatory process involving the gingiva and mucosa. The term is a compound word where the second term, “stomatitis,” is derived from the Greek word stoma, which means mouth. The term encompasses any intraoral inflammatory process located within the oral cavity.

  • herpetic gingivostomatitis: a herpes simplex viral infection of the oral soft tissues indicated by redness, development of many vesicles, tender ulcerations, fever, and lymphadenopathy.

ginglymoarthrodial joint

n: a joint that involves hinging and gliding movement during function; it has a ginglymus and arthrodial form.

ginglymus joint

n: joint involving hinging movements during function.

glenoid fossa

n: the concavity in the temporal bone at the root of the zygomatic arch that receives the mandibular condyle.


n: pain in the tongue.


n: partial or total resection of the tongue.


n: painful or burning sensation in the tongue.


n: plastic or altering surgery of the tongue.

glucose tolerance test

n: a laboratory test that denotes a patient’s ability to regulate blood sugar level after carbohydrate intake. One of the best laboratory tests (in terms of reliability) for detecting diabetes mellitus.


n: a polysaccharide that is important in tissue repair, hydration, and joint health. Also known as mucopolysaccharide.


adj: relating to the anatomy or function of the maxilla or mandible.


n: a reference point commonly used in orthodontic evaluation (especially radiographically) of the skull, which designates the most inferior and outward point of the bony chin as measured at the midsagittal plane.


n: an instrument used to measure maximal bite force and masticatory efficiency. Also known as occlusometer.


n: the science of relating tooth position, anatomy, and function to the exact movements of the temporomandibular joints bilaterally, in an attempt to define ideal masticatory function and stability. Also known as neuromuscular dentistry.

Golden Proportion

n: a mathematical progression of numeric expressions thought to have ideal esthetic value. It describes the ideal dimensions and visual relationships of the human dentition, as well as human facial dimensions. Dr Eddy Levin, of London, England, found that by applying the Golden Proportion to the 8 maxillary anterior teeth (1st bicuspid to 1st bicuspid) ideal esthetics could be achieved. The ratio is 1.618 to 1. It has been accepted that the Golden Proportion exists in natural dentitions as observed from the labial surfaces, the ratio of the widths of cuspids to lateral incisors as well as central incisors to lateral incisors. The 4 front teeth, from central incisor to 1st bicuspids are the most significant part of the smile and are in the Golden Proportion to each other. Also, the combined width of the central incisors compared with their height follow the Golden Proportion.

gothic arch tracer

n: a device rarely used in contemporary dental practice that determines an accurate, verifiable, and reproducible centric relation position and the proper occlusal vertical dimension.

gothic arch tracing

n: see central bearing tracing.


n: (1) any tissue or organ transferred to a patient; (2) any tissue or organ from a donor or a second site in the recipient used for implantation or transplantation into the recipient at the required site; (3) a piece of viable (living) tissue positioned in contact with injured tissues to afford a scaffold for repairing a defect or correcting a deficiency; (4) to stimulate closure between separate tissues.


n: An exophytic mass representing a proliferative response of the tissue. When evaluated microscopically it is characterized by macrophages typically surrounded by lymphocytes. Giant cells are often present.

granulomatous tissue

n: Inflammatory process resulting in a distinctive pattern. Microscopic evaluation typically reveals epithelioid cells derived from histocytes. Surrounding cells are predominantly lymphocytes.


n: a unit of absorbed radiation dose equivalent to 100 rad. Abbreviated Gy.

guided tissue regeneration

n: procedure that helps to regenerate lost periodontal structures or alveolar processes in the jaw. Grafting materials are commonly used to guide the growth of the new tissue and to prevent the ingrowth of unwanted tissue.


Hader bar

n: a rigid bar that connects 2 or more abutments designed for the retention of a restoration(s). The removable restoration contains housings that are machined to clip over the bar.


n: malodorous breath often offensive to others. Halitosis results from a variety of causes, such as bacteria on the tongue, periodontal disease, poor oral hygiene, systemic disorders, and consumption of some food types. Also known as fetor ex ore, fetor oris, and stomatodysodia.

Hanau’s Quint

n: the 5 factors affecting the occlusal balance of complete dentures: (1) incisal guidance, (2) condylar guidance, (3) cusp height, (4) plane of occlusion, and (5) compensating curve. Hanau’s Quint was first explained by Rudolph Hanau in 1926.

hard palate

n: bony partition separating the oral and nasal cavities.

Hawley appliance

n: a removable upper appliance that covers the anterior hard palate and contains a labial archwire and an anterior bite plate. The Hawley appliance—usually made from acrylic—is used for orthodontic treatment, the treatment of the temporomandibular joint and associated muscle spasms, prosthodontic diagnosis and treatment, and wound healing.

healing cap

n: a cover for an implant fixture that guides gingival healing and gingival cuff formation.

healing screw

n: the cover for an implant fixture that protects the fixture during the healing phase after surgical placement of the implant body. The purpose of the healing screw is to ensure access to the internal threaded cavity for later use.


n: the distal end of a denture.


n: a confined gathering of extravasated blood, usually clotted, that presents as a mass in a tissue, organ, or space.


n: an ultrastructural feature located on the basal surface of some epithelial cells forming the position of attachment between the basal surface of the cell and the basement membrane, or the conditioning film of a dental implant.


n: stopping hemorrhage (bleeding).


n: an agent, apparatus, or instrument that may be used to stop hemorrhage.

hemostatic agent

n: any compound, such as aluminum chloride or ferric sulfate, that stops or decreases hemorrhage. Oftentimes these agents are used to control bleeding during impression taking, restoration delivery, and surgical procedures.

herpetic gingivostomatitis

n: see gingivostomatitis.


adj: lesions that resemble herpetic (herpes) lesions.


n: a tissue graft where the species of the donor and recipient are different. Also known as a xenograft.

heterotopic pain

n: pain felt in a site distant from the site of origination. See also referred pain.

high lip line

n: an extreme elevation of the inferior border of the upper lip whereby all the maxillary teeth and part of the alveolar process are visible while naturally smiling.

high noble metal alloy

n: a dental casting alloy composed of a minimum of 60% noble metal (gold, platinum, palladium, rhodium, ruthenium, iridium, osmium) by weight with at least 40% gold as classified by the American Dental Association.

hinge axis

n: an imaginary line created by rotation of the mandible through the sagittal plane.

hinge joint

n: a joint that allows movement in only 1 plane, such as a door hinge. See also ginglymus joint.

hinge position

n: orientation of parts allowing hinge movement between them.


n: the cytologic and histologic study of disease at the microscopic level.


n: a type of tissue graft where the donor and recipient are of the same species. See also allograft.

hybrid denture

n: slang for any dental prosthesis that has been changed from the usual form.

hybrid prosthesis

n: slang for any prosthesis, such as fixed dental prostheses, removable dental prostheses, or maxillofacial prostheses, that does not follow traditional design. Often it is used to designate a dental appliance made of various materials, various types of denture teeth (porcelain, plastic, composite), acrylic denture resins of variable nature, or differing metals or designs.


n: an inorganic compound, Ca5(PO4)3(OH), found in the mineralized matrices of bone and teeth that provides hardness to these structures. Various synthetic forms are used in ridge augmentation and intrabony defects, as well as coating of dental implants.

hydroxyapatite ceramic

n: a synthetic composition of calcium and phosphate in physiologically acceptable ratios. It is a rigid, nonresorbable, biocompatible material used for dental implants and augmentation of deficient alveolar ridges.

hygienic (sanitary) pontic

n: a pontic (suspended crown in a fixed bridge) that is simpler to clean because it has a rounded or bullet-shaped cervical form and does not contact the edentulous ridge.


(hypoalgesia) n: reduced sensitivity to pain that results from a raised pain threshold.


n: amplified sensitivity or sensibility to pain that results from a lowered pain threshold.

hyperbaric chamber

n: an enclosed space or tube that accommodates a patient and subjects the patient to ambient gas pressures >1 atm.

hyperbaric oxygenation

n: the administration of oxygen in an enclosed space larger than atmospheric pressure; also called hyperbaric oxygen therapy.


n: an extreme accumulation of blood in a tissue due to vascular engorgement.


(hyperaesthesia) n: an abnormal increase in sensitivity to sensory stimulation.


n: a condition characterized by an unusually increased or high blood glucose, typically >11.1 mmol/L, however, symptoms may not be noticeable until even higher values are reached, such as 15-20 mmol/L. A patient with a consistent range between ~5.6 and ~7 mmol/L is considered hyperglycemic, values >7 mmol/l are considered a state of diabetes. Chronic levels >7 mmol/L can produce organ damage.


n: extreme development of keratin by epithelial cells.


n: abnormal quantities of mineral elements in calcified tissue.


n: an uncharacteristically increased sensitivity to odors.


n: a limited overgrowth of bone in one particular area.


n: enlargement of normal tissue or structure due to an increase in cell number production in the tissue, oftentimes as a result of irritation of the tissue.

hyperplastic tissue

nn: surplus tissue that is often caused as a response to chronic irritation that stimulates overproduction of the cells in the tissue.


adj: an exaggerated reaction of the immune system to an antigen that is expressed on a spectrum ranging from allergy to anaphylaxis.


n: in the absence of tumor formation, it is an increase in the size of an organ or tissue as the result of an increase in the dimensions rather than the number of the constituent cells.


n: lessened or reduced tactile sense.


(hypoageusia) n: reduced sense of taste, including sweet, sour, salty, and bitter substances.


n: a speech characteristic caused by insufficient resonance of air in the nasal cavity such that the speaker sounds as though he or she has a cold. Also known as denasality.


n: one of numerous conditions that resembles osteogenesis imperfecta. Triggered by an inherited metabolic disorder that results in low levels of the enzyme alkaline phosphatase. Contingent on the severity of the disease it can affect skeletal and dental development.


n: a congenital disorder that is the result of a decrease in the typical number of cells and manifests as defective or incomplete organ/tissue development.


Idiopathic resorption

n: see under resorption.

immediate denture

n: a removable prosthetic device fabricated to replace a natural tooth or teeth immediately upon its removal.

immediate mandibular lateral translation

n: Leaving the position described as centric relation, the non-working-side condyle moves straight and medially, which is considered the translatory portion of lateral movement.


n: an alloplastic device or material that is placed into the body. See also dental implant.


v: to place a device or material into the body.

implant, oral

n: an alloplastic device or structure that is surgically placed into, on top of, or in the alveolar bone of the maxillary or mandibular jaw bones. The device’s whose abutment(s) emerge(s) through the oral mucosal tissues to provide support or retention for a dental prosthesis

  • blade implant: a flat, blade-shaped endosseous implant most commonly made of metal, which gains its support from a horizontal dimension of bone, it maybe perforated, smooth, fluted, textured, coated, or wedge shaped, and it may have single or multiple abutments for attachment of the prosthesis.
  • endodontic-endosseous implant: a flat, blade-shaped endosseous a pin-shaped device that is placed into the root canal space and extends past the tooth’s apex into the apical bone.
  • endosseous implant: an implant positioned into the jaw’s alveolar and/or basal bone for the purpose of supporting a dental prosthesis.
  • fibro-osseous (fibro-osteal) integrated implant: a dental implant that has a fibrous connective tissue interface located between the implant and the adjacent bone.
  • osseointegrated implant: a direct physical and functional relationship between organic viable bone and the external surface of an stationary, load-bearing implant as revealed when viewed under a light microscope.
  • ramus frame implant: a complete mandibular arch implant with a tripodal design that consists a horizontal supragingival connecting bar with terminal left and right posterior ends that pass through the soft tissue and enter the bilateral rami of the mandible. There is also an inferior anterior plate that passes through the soft tissue and enters the bone of the symphyseal area.
  • root-form implant: an endosseous implant that obtains support from the vertical height of alveolar or basal bone. It is frequently made from metal or ceramic and may have a cylinder shape that is tapered, threaded, perforated, solid, and/or hollow. The surface may be coated, smooth, or textured.
  • subperiosteal implant: a dental implant placed on the external surface of the maxillary or mandibular alveolar or basal bone. It is designed to provide support for attachment of a dental prosthesis. The implant is not designed to enter the bone, although there may be retentive screws that do or, with time, the implant may settle into the supporting bone.

implant abutment

n: a part or section of an implant or that which is connected to the implant that allows for the connection to a crown, prosthesis, or other device.

implant connecting bar

n: slang for a device made of metal or other materials that attaches to 1 or more implant abutments and serves to act as a framework.

implant crown

n: slang for a crown that is attached to the abutment of an implant as opposed to being attached to a natural tooth.

implant dentistry

n: the field of dentistry relating to implants and involving all aspects of implantology from the initial planning phase to the care and maintenance oriented toward enhancing the likelihood of a long-term successful outcome.

implant fixture

n: another name for an implant.

implant infrastructure

n: when applied to endosseous cylindrical implants this slang term refers to the inferior portion.

implant interface

n: the portion of the implant that provides a surface upon which the surrounding host tissues interact.


n: traditionally, the study or science of placing and restoring dental implants.

implant prosthesis

n: a prosthetic device attached to 1 or more implants.

implant prosthodontics

n: the area of prosthodontics that deals with the replacement of maxillofacial structures (including teeth) by prostheses that attach to dental implants.

implant substructure

n: (1) the metal framework of a subperiosteal implant that is beneath the soft tissue; (2) metal framework (skeleton) placed beneath soft tissues in contact with bone and stabilized by screws into bone; supports prosthesis, usually with superstructure apparatuses.

implant surgery

n: the surgical placement of an implant.


n: a replica in a negative form of areas of the oral cavity; often used for dental treatment planning and/or dental prosthesis construction.

impression coping

n: a device used in an impression to relate an implant position to the adjacent and opposing dentition for the purpose of fabricating a prosthetic crown. Multiple impression copings can be used to relate multiple implants.

incisal guidance

n: the motion of the mandibular anterior teeth incisal edges against the lingual surfaces of the maxillary anterior teeth during a protrusive movement that usually causes a separation of the posterior teeth. A lack of this guided movement of the anterior teeth may allow free motion of the jaws, which may cause undue wear or promote parafunction or bruxism.

incisal guide angle

n: the angle formed by the plane of the occlusal table and the line that connects the incisal edges of the maxillary and mandibular incisors.


n: a cut or surgical wound created by a sterile scalpel, electrosurge tip, laser tip, or similar device

incision and drainage

n: the surgical procedure of cutting into a lesion to allow the release of an exudate.

incisive foramen

n: an anatomic hole, usually found lingual to the maxillary central incisors, that allows passage of the vascular and neural tissues that supply the anterior maxilla.

incisive papilla

n: see under papilla.


n: the act of inducing or causing to occur as referenced in the induction of bone formation.


v: toughen or harden; make hard.


adj: capable of causing infection; caused by or capable of being transmitted by infection; infective.


n: a localized protective reaction of tissue to irritation, injury, or infection elicited by proximate microbes and/or tissue injury and associated with pain, redness, swelling, and possible loss of function. Its purpose is to obliterate, dilute, or wall off the harmful agent(s) and isolate the offended tissue(s). It is both a cellular and vascular reaction to localized tissue damage.


n: a metal, ceramic, or resin framework onto which a second framework or prosthesis will be placed or attached using chemical or physical means.

in situ

adj: in position; in the place where something is occurring or has/does occurs.


n: (1) in dentistry, the interior surface of a denture; (2) a figure carved or engraved below the surface of a hard material such as stone that would yield an image in relief from an impression taken of the design; (3) something carved in intaglio.


n: the area between the alveoli.

interalveolar crest

n: the most coronal portion of the interdental bony septum.

interalveolar septum

n: alveolar and trabecular bony partition between adjacent tooth sockets.

interarch distance

n: the vertical distance between the maxillary and mandibular arches at a specified vertical dimension.


adj: in dentistry refers to the area between the mandibular condyles.

interim dental implant

n: a temporary dental implant that allows for the use of a provisional prosthesis. These temporary implants may also be used as stents to guide tissue healing and prevent soft tissue collapse into a healing surgical site. These implants have smooth machined surface to allow easier removal. Also known as provisional dental implant.

interim endosteal dental implant abutment

n: a type of dental implant abutment used only for a limited time to guide healing or shaping of the adjacent tissues and/or attachment of a transitional prosthesis.

interim prosthesis

n: a prosthesis typically used before fabrication of a definitive dental or maxillofacial prosthesis. It can be fixed or removable and is designed to enhance esthetics, stabilize teeth, or improve function for a limited time. Such prostheses often help guide the clinician in designing the appearance and function of the final prosthesis. Also known as a provisional restoration.


adj: between the maxillary and mandibular jaws.

intermediate abutment

n: a natural tooth or dental implant located between terminal abutments that provides added stability and retention for the fixed or removable prosthesis.

internal connector

n: a device of varying geometric designs used to unite parts of a fixed partial denture.

internal derangement

n: abnormal positioning of the articular disc in relation to the condyle, fossa, or articular eminence; a deviation in form or function of the joint capsule.


adj: the working space between the occlusal surfaces of the opposing dental arches.

interocclusal clearance

n: the space between opposing arches when the mandible is in the rest position; also known as freeway space.

interocclusal record

n: a record or registration of the positional relationship of the teeth or jaw position.

interocclusal rest space

n: the measured difference in tooth position between vertical dimension of occlusion and vertical dimension at rest.


adj: positioned between parts or spaces of a tissue envelope.


adj: within the bone; also known as infrabony.


adj: found within the confines of mucosa; for example, submucosal inserts attached to removable appliances to add retention.


adj: found within bone.

intrinsic coloring

n: shading or actual coloring found within the material of a restoration.


n: apical movement of a tooth beyond the normal boundaries of a tooth-periodontal ligament apparatus.


adj: belonging to or occurring on the same side of the body.


n: an allogenic graft transferred between monozygotic twins. Also called isogeneic graft, syngraft.



n: either of 2 bony structures (maxilla or mandible) that are intended to bear natural teeth or support prosthetic teeth.

jaw malposition

n: abnormal or anomalous position of the mandible.

jaw relation

n: any relationship of the mandible to its opposing maxilla.


n: where 2 or more skeletal bones meet (intersect); functions to allow the movement of the individual bones. See also temporomandibular joint.


n: the process of joining together, as in 2 different structures.

  • cementodentinal junction: the zone where the dentin and cementum meet.
  • cementoenamel junction: the zone where the cementum and enamel meet at the cervical section of the tooth.
  • dentinoenamel junction: the zone where the dentin and enamel meet.
  • mucogingival junction: the zone where the gingiva and alveolar mucosa meet.

junctional epithelium

n: found at the base of the gingival sulcus, it is a single layer or multiple layers of nonkeratinized epithelial cells that adhere to the tooth surface at this location. A calibrated periodontal probe is used to measure the depth of this gingival sulcus. Also known as epithelial attachment.

juvenile periodontitis

n: a deteriorating periodontal disease found in adolescents in which the periodontal damage is greater than what would normally be expected when considering the localized irritating factors found on adjacent teeth; inflammatory changes become excessive leading to observed bone loss, tooth migration, and/or extrusion. See also periodontitis and the subcategory aggressive periodontitis.


n: 2 things placed side by side or in close proximity.



n: a device used for holding something in a desired position. In dentistry, this is typically understood to mean a magnetized alloy fixed to 1 component of a restoration to which a magnet may adhere.

Kennedy classification of removable partial dentures

n: the most widely accepted and used classification system for removable partial dentures. Kennedy classification is based on the location of the missing teeth.

  • Class I: characterized by bilateral edentulism located distal to the remaining natural teeth.
  • Class II: characterized by unilateral edentulism distal to the remaining natural teeth.
  • Class III: characterized by unilateral edentulism when natural teeth are located both mesially and distally to the edentulous area.
  • Class IV: observed when the edentulism is located mesially to the natural teeth.

keratinized gingiva

n: the portion of the gingiva extending from the mucogingival junction to the gingival margin.


n: a cutaneous cyst that is similar to an epidermoid cysts but is not limited to a specified location on the body. They are frequently reported in persons with nevoid basal cell carcinoma syndrome.


n: a horny, keratinous growth, particularly on the skin. Also known as a wart or callus.


n: an interlock connection that uses a matrix and patrix between the units of a fixed dental prosthesis. Once it is soldered in place it holds the pontic in its proper relationship to the edentulous ridge and the opposing teeth and reinforces the connector.



adj: of or relating to the lip.

labial flange

n: the ridge, edge, or projection of a denture that is positioned toward the vestibule located on the lip side of the mouth.

labial vestibule

n: the segment of the oral cavity that is anterior to the bicuspids and lies between the lips and the adjacent teeth or the corresponding edentulous residual ridge.

Lactobacillus spp

n: gram-positive bacteria that contribute to caries progression. The bacteria are rodshaped, are motile, and can exist under anaerobic conditions.


n: a thin layer, membrane, plate, or scale, as of bone, tissue, or cell walls.


n: one of the thin layers or flat plates of a larger composite structure, such as bone or tissue.

lamina dura

n: the sheet of compact bone that forms the tooth alveolar wall or tooth alveolus.

  • crestal lamina dura: the layer of compact bone existing at the alveolar crest.

lamina propria

n: connective tissue that is highly vascularized and lies beneath the basement membrane lining the epithelium; vascularized connective tissue layer of mucous membranes.


n: a principal high molecular weight glycoprotein component of the basement membrane that aids in cellular adhesion.

lancinating pain

n: a sharp, piercing, cutting, knife-like pain that is usually intermittent.

land area

n: the area of a dental cast that denotes the end of the replicated anatomic surface of the mouth and the beginning of a border of the cast.


v: to cover, fold over, or lie on top of as in the ridge lap of an artificial tooth that covers the residual ridge.


n: the acronym for light amplification by stimulated emission of radiation. A technique that converts light from several frequencies into an intense, visible, small, nondivergent, monochromatic radiation beam that is capable of creating immense localized heat and power when concentrated and directed at a short distance.

laser therapy

n: the use of concentrated light beams to specifically cut, burn, remove, or destroy soft tissue.

laser welding

v: the use of intense beams of light amplified by stimulated emissions of radiation (laser) that create sufficient heat to join metal components.

late closing click

n: a sound made in the temporomandibular joint just before jaw closure as the disk slips from anterior displacement to its original position between the glenoid fossa and the head of the condyle.

late opening click

n: a sound made in the temporomandibular joint just before maximum jaw opening as the disk slips from anterior displacement to its original position between the glenoid fossa and the head of the condyle.


adj: as related to the midline, any position that is right or left of that position.

lateral condylar inclination

n: the angle the moving condyle makes within the horizontal plane (superior- inferior movement) and the median plane (anterior- posterior movement) plane as the jaw moves laterally. The condylar deviation or the degree of deviation (slant) from its original horizontal and vertical orientation when it is moved to one side.

lateral interocclusal record

n: bite registrations of the teeth in right and then left lateral working position, used to estimate the opposite side lateral condylar path and inclination.

lateral relation

n: an obsolete term for the positional relationship between the mandible and the maxillae when the lower jaw is to the left or the right side of the centric relation.


n: the movement of the mandibular condyle on the working side in the horizontal plane. This description of mandibular condyle movement is used in conjunction with other types of condylar movement in other planes, such as laterodetrusion, lateroprotrusion, lateroretrusion, and laterosurtrusion.

leaf gauge

n: a device consisting of a set of blades or leaves of graduated thicknesses that is placed in the oral cavity to make accurate measurements between 2 points or to provide a metered separation.

lengthening of the clinical crown

n: a surgical procedure performed to increase the extent of supragingival tooth structure by apically repositioning the gingival tissue around the tooth; often includes removing a portion of the surrounding alveolar bone. This procedure is typically performed for restorative or esthetic purposes.


n: any pathological change to a tissue or organ, local in nature, caused by injury, surgical procedures, chemicals, or infection that may result in a loss of normal function.


n: a thread, wire, fillet, suture (eg, gut, nylon, silk) or the like, tied tightly around such structures as the blood vessel or pedicle of a tumor for the purpose of constricting it.

  • orthodontic ligature: a wire or other material used to secure an orthodontic attachment or tooth to an archwire.


n: the perception by which objects are distinguished as white or gray and light or dark; equivalent to shading in grays, in the Munsell Color Order System. Lightness (other name brightness) is 1 dimension of the 3 achromatic dimensions (the others being hue and saturation) describing the 3-dimensional nature of color.

linear gingival erythema

n: a distinct erythematous linear band limited to the free gingiva; commonly a manifestation of immunosuppression that does not predictably respond to plaque removal.

linear occlusion

n: an occlusal arrangement of artificial teeth developed to enhance stability for complete denture prosthetics. This arrangement is described as a mandibular flat plane or monoplane arrangement, opposed by a line or bladed arrangement of the maxillary teeth with no anterior interferences in protrusive or lateral movements.

line of occlusion

n: a line passing through the cusp tips of adjacent teeth on one side of the arch forming a plane when viewed horizontally. See also occlusal plane.


adj: related to the tongue; adjacent to or toward the tongue.

lingual flange

n: the portion of a mandibular denture that occupies the space between the tongue and residual alveolar ridge.

lingual flange

n: the portion of a mandibular denture that occupies the space between the tongue and residual alveolar ridge.

lingual inclination

n: a lingual deviation of a tooth or teeth from the vertical plane

lingualized occlusion

n: an occlusal relationship commonly used in full denture prostheses characterized by maxillary palatal cusp contact against the central fossa of the mandibular teeth, where the buccal cusps of the mandibular teeth do not contact the opposing maxillary teeth and the position of the mandibular teeth is lingual to the alveolar ridge.


n: an occlusal relationship where the teeth are located in a lingual position to their normal location.


n: deviation of a tooth lingual in direction to the regular arch alignment.

lip switch operation

n: a procedure in which tissue obtained from one lip is transferred to the other lip of the same patient. Also used to describe a modified vestibuloplasty procedure.

loading dose

n: the larger dose given at the initiation of treatment in order to quickly achieve the desired blood or tissue final concentration.

local contributing factor

n: an event occurring locally that can influence the manner in which a disease or condition is manifested.

low lip line

n: an imaginary line passing longitudinally through the center of a body.

long axis

n: (1) the lowest position of the inferior border of the resting upper lip; (2) when the patient voluntarily smiles or retracts the lips, it the lowest position of the superior border of the lower lip.

Lucia jig

n: eponym (Victor O. Lucia) for an anterior muscle programming device used to obtain an accurate dental arch centric relationship by allowing the condyles to seat in their most superior position.


n: the intensity of light emitted from a surface per unit area.


v: to attach 2 surfaces by means of a cement or other adhesive material.



n: a completely flat circumscribed change in the color of skin that can only be appreciated by visual inspection and not by touch. It is neither raised nor depressed, does not show a change in the skin’s texture or thickness, and is usually <10 mm in diameter.

major aphtha

n: a type of recurrent apthous stomatitis that occurs in 10% to 15% of patients with the condition; usually manifested by the appearance of 1 or 2 large, painful ulcerations on movable, nonkeratinized oral mucosa, lasting for up to 6 weeks.


adj: concerning the lower jaw (mandible).

mandibular anteroposterior ridge slope

n: usually produced in an edentulous patient by resorption of alveolar bone of the lower jaw (mandible). This slope of the crest of the ridge from the third molar region to the greatest anterior aspect relative to the inferior border of the mandible as observed in profile is of particular significance for the design and fabrication of a lower prosthesis as it can affect movement of the denture in an anterior direction during normal occlusion and function.

mandibular dislocation

n: a unilateral or bilateral displacement of the mandibular condyle(s) out of the glenoid fossa(e) that precludes normal occlusion of the teeth.

mandibular dysplasia

n: a condition in which the 2 halves of the mandible lack symmetry in size or form.

mandibular equilibration

n: adjustments to the occlusal surfaces of the natural teeth or prosthetic teeth in the lower arch (mandible) that place the mandible in a condition whereby forces placed on it by the opposing dentition are neutralized and a state of equilibrium is created.

mandibular glide

n: an obsolete term referring to the lateral, forward, and intermediate movements of the mandible, which occur when teeth or surfaces that otherwise occlude are in contact.

mandibular hinge position

n: an obsolete term referring to the mandibular position that allows for hinge axis-type movements upon opening and closing relative to the maxilla.

mandibular micrognathia

n: a mandible that is atypically small and characteristically associated with a diminished chin form.

mandibular movement

n: movement of the mandible as it changes position relative to the maxilla or other structures.

mandibular nerve

n: a part of the trigeminal nerve referred to as the third division. The trigeminal nerve exits the skull via the foramen ovale. The mandibular nerve feeds motor innervation to the muscles of mastication, tensor veli palatini muscle, tensor tympani muscle, anterior belly of the digastric muscle, and mylohyoid muscle. Sensory innervation is provided to the mandibular gingiva and teeth, epithelium of the anterior two-thirds of the tongue, skin of the lower face, and floor of the mouth.

mandibular relationship record

n: a record or registration of the correlation of the mandible to maxilla.

mandibular repositioning

n: a device or method causing the mandible to close in an altered position.

mandibular retraction

n: movement of the mandible posteriorly by surgical or orthopedic/orthodontic means.

mandibular staple

n: a dental implant that is placed transosteally from the inferior border of the mandible with threaded rods that pass through the anterior body of the mandible and emerge through the oral mucosa between the mental foramen.

mandibular translation

n: anterior movement of the mandible on opening.

mandibular trismus

n: tonic contraction of the muscles of mastication that leads to limited opening of the mandibular jaw.

marginal gingiva

n: the terminal edge (most coronal aspect) of the gingiva surrounding the teeth, forming the wall of the gingival sulcus.

marginal ridge

n: the rounded enamel border at the junction of the occlusal and mesial/distal tooth surfaces.

master impression

n: the negative likeness reproduction of the dental arch characterized by high dimensional accuracy and surface detail made for the construction of a master cast on which the prosthesis will be fabricated.

maxillary micrognathia

n: a condition in which the volume of maxillae bone is less than normal and usually visible as smaller bone structures found in the middle third of the face. This smaller middle third of the face occludes with a normal-sized mandible (lower third of the face).

maxillary protraction

n: a condition in which the upper jaw bone (maxillae) volume of bone and its supporting tissue structures are less than normal for the size of the mandibular bone and its supporting tissue structures.

maxillary sinus

n: bilateral anatomic space located superior to the upper jaw (maxillary) posterior alveolus.

maxillary tuberosity

n: most posterior portion of the upper jaw alveolar ridge bone.


n: removal of part or all of the maxillary (upper) jaw bone structure. Also known as a maxillary resection.


adj: concerning or relating to the teeth, jaws, face, head, and neck.

maxillofacial prosthesis

n: a prosthesis used as a substitute for or to reposition stomatognathic or craniofacial structures. The prosthesis is usually removable but may be fixed with the help of teeth or dental implants. Explanatory terminology may be used to describe the time utilization for the prosthesis, such as surgical, interim, and definitive.

maxillofacial prosthetic adhesive

n: a material used to hold or adhere an external facial appliance or device to the skin and its accompanying structures adjacent to the margins of an anatomic defect for the purpose of preventing its dislodgement during normal function.

maxillofacial prosthetics

n: the subspecialty of dental prosthodontics that is concerned with the prosthetic replacement or reconstruction of lost stomatognathic and/or craniofacial structures.

maxillomandibular dysplasia

n: disharmony between the right and left portions of the mandible and the maxillary jaw.

maxillomandibular fixation

n: a temporary fixed connection of the maxillary and mandibular teeth, typically with wire, for use in treating a mandible fracture.

maxillomandibular relationship

n: any spatial relationship of the mandible to the maxilla.

maxillomandibular relationship record

n: a registration of any position of the mandible with respect to the maxillae. These records often capture the vertical, horizontal, and oblique planes of relationship.

maximal intercuspal contacts

n: position that results in maximal tooth contact between the mandibular and maxillary dental arches when the jaws are in a closed position.

maximal intercuspal position

n: sometimes referred to as centric occlusion, this is the best fit of the upper teeth to the lower teeth regardless of the position of the mandibular condyle.

maximum bite force

n: the most load a patient can generate by intentionally biting down on an indicating device so as to measure the greatest load that patient can generate. This measurement may influence prosthetic design, especially if the patient can develop extreme loads.

median line

n: a hypothetical line that divides the body into left and right halves.

median mandibular point

n: an obsolete term referring to a point in the median sagittal plane that is in the center (measuring anterior to posterior) of the mandibular ridge.

median plane

n: a hypothetical plane passing from anterior to posterior that divides a body into right and left halves.


n: movement of the nonworking condyle toward the midfacial sagittal plane.


n: patches of pigmentation on the oral mucosa.


n: thin layer of tissue that lines a cavity, separates a space or organ, or envelops a vessel. An example of a membrane used in surgery is the thin material used in various periodontal or guided bone regenerative procedures. The membrane source may be autogenous, allogeneic, or synthetic.


n: surgical removal of the intra-articular disk. See discectomy.


n: as related to the temporomandibular joint, the crescent-shaped fibrocartilaginous disk that aids in the articulation of the joint.


n: one of two objects whose colors appear to match when viewed under certain conditions but under alternate viewing conditions may appear different.

metameric pair

n: two objects matching in apparent color under some lighting conditions but not others.


n: pairs of objects that match in a given hue of light but not in others.


n: transformation of 1 type of an adult cell from a normal to an abnormal state.


n: transmission of pathogenic microorganisms or cancerous cells from 1 body part or organ, via blood vessels or lymphatics, to other sites elsewhere in the body that are not directly connected.


n: having an abnormally small tongue.


n: abnormal smallness of the jaw, particularly the mandible, that can be congenital or acquired. See also mandibular micrognathia and maxillary micrognathia


n: having an abnormally small oral orifice.

midfacial fracture

n: fracture of the middle third of the face, including zygomatic, maxillary, nasal, and other associated bones of the midface.

mill in

v: a mechanical procedure that involves modifying and refining occluding surfaces by using abrasive materials.


n: a facsimile representation of something; an analog or emulation used for display purposes. See also cast.

modified ridge lap

n: a ridge lap surface of a pontic that is reduced, shaped, and adapted to only the facial or buccal aspect of the residual alveolar ridge.


n: any substance that changes the color or properties of a given substance.


n: a matrix used to fabricate or duplicate a prosthetic device.

mold chart

n: representation of the different dimensions of a denture tooth’s (or teeth’s) shape and size.

mold guide

n: a selection of teeth demonstrating the dimensions and shape of commercially available denture teeth.


n: the chemical initiator of a polymerization process.


m: the occlusal surface of teeth where all cusp heights are within the same plane.

monoplane articulation

n: the arrangement of teeth in a single plane of occlusion.

monoplane occlusion

n: the arrangement of teeth where tooth contact in all excursions occurs in a single plane of occlusion.

MORA device

n: acronym for mandibular orthopedic repositioning appliance; an appliance designed to optimize jaw relationships and neuromuscular balance.


n: the condition of being in a diseased state.


v: the laboratory procedure of attaching a cast to an articulator or cast relater that maintains the occluded relationship of maxillary and mandibular dental casts to each other, yet the casts may be separated as the instrument facilitates the opening and return of the casts to the intended occluded relationship.


n: when maxillary and mandibular dental casts are attached to an instrument (articulator) that maintains the occluded relationship of dental casts to each other, yet the casts may be separated as the instrument facilitates the opening and return of the casts to the intended occluded relationship. See also split-cast mounting.

mounting plate

n: removable flat, round components made of metal or resin that facilitate the attachment of dental casts to the upper and lower members of an articulator

mouth guard

n: a removable dental appliance made of resilient or hard materials that are used to protect the teeth and surrounding tissues from injury. See also occlusal guard.

mouth stick

n: a prosthesis that is held in position by the teeth and used by a disabled person to perform certain functions (eg, as a rod for the purposes of pointing).


adj: pertaining to the oral mucosa and gingiva or to the line of demarcation between them. The keratinized gingiva and adjacent alveolar mucosa tissues cover and protect the alveolar process.

  • mucogingival deformity: Abnormal dimension, morphology, and/or interrelationship between gingiva and alveolar mucosa.
  • mucogingival junction: The meeting point of the gingiva and alveolar mucosa.
  • mucogingival surgery: The intended incision or cutting of the oral mucosal tissues for the purpose of accessing the underlying bone or correcting an anomaly.
  • mucogingival therapy: Procedures intended to correct defects in morphology.

mucogingival deformity

n: see under mucogingival.

mucogingival junction

n: see under mucogingival.

mucogingival surgery

n: see under mucogingival.

mucogingival therapy

n: see under mucogingival.

mucolabial fold

n: the line, bend, crease, or area of change as the oral mucous membrane passes from its role as the mucosal tissue of the mandible or maxilla to form the lip.


n: oral mucosa that contains fibrous lamina propria, contains no submucosa, and is attached to the underlying periosteum covering the bone. Attached gingiva is an example of mucoperiosteum; it is a term synonymous with “full-thickness flap” indicating the inclusion of periosteum and surface mucous tissue during the flap elevation.


n: mucous membrane that forms the soft tissue barrier to the environment, particularly in the oral cavity. It is loosely attached to the periosteum; is movable; and consists of epithelium, basement membrane, and lamina propria.

mucosal implant

n: See mucosal insert.

mucosal insert

n: a mushroom-shaped alloplastic device, used mainly during the 1970s and 1980s, that was embedded in the intaglio surface of a removable maxillary tissue-borne prosthesis that engages surgically prepared undercuts into the palatal mucosal tissue upon which it rests.


n: a painful inflammatory response of the oral mucous membrane. May be caused by local irritants, including prostheses, or may be systemically induced.


adj: (1) refers to oral mucosa at a state of rest, without displacement; (2) prohibiting the flow of mucus.


n: (1) along with serous fluid, one of the 2 main components of saliva; (2) a viscous fluid, consisting of the secretions of mucous glands, along with cells and inorganic components.

Munsell chroma

n: one of the three main components of the Munsell Color Order System. It indicates the purity or saturation of any particular color, from vivid to washed out.

Munsell Color Order System

n: a color classification system that uses numeric nomenclature to characterize any color using hue, value, and chroma. This is the basis for most shade matching systems in dentistry.

Munsell hue

n: one of the three main components of the Munsell Color Order System. It is divided into 5 principal color families: red, yellow, green, blue, and purple.

Munsell value

n: one of the three main components of the Munsell Color Order System. It indicates the relative lightness or darkness of a particular color, from white to neutral gray to black.

muscle contracture

n: a pathologic condition in which there is permanent shortening and loss of strength and flexibility in a muscle.

muscle fiber

n: see under fiber.

muscle hyperalgesia

n: increased awareness of pain in a muscle out of proportion to physical findings.

muscle hypertonicity

n: hyperactivity of a muscle related to increased involuntary contractions.

muscle relaxant

n: a medication used for treating muscle tension or spasm.

muscle spasm

n: an abrupt involuntary contraction of a muscle that is associated with pain and can occur even when the muscle is at rest.

muscle spasticity

n: a clinical situation when opposing muscles have increased contractibility and tension impeding movements of the agonistic muscles.


n: slang for a muscle contraction initiated to avoid the pain associated by passively stretching the muscle.

muscular splinting

n: muscular contraction at a nonrest state that impairs function. It is associated with involuntary movements.

musculoskeletal pain

n: pain that is derived from a muscle and/or skeleton that may also involve the muscular tendons and joints.

mush bite

n: an obsolete slang term for a record of the mandible in relation to the maxilla without using baseplates but instead by using a nonrigid material alone (ie, wax).

mutually protected articulation

n: an occlusal scheme where all posterior teeth disocclude during mandibular movements while the occlusion is supported by the anterior teeth. At maximum intercuspation the posterior teeth reduce the occlusal forces applied on the anterior teeth so the forces applied on the anterior teeth are not excessive.


n: a compound Greek word formed by the word myo, which means muscle, and algos, which means pain or soreness. It indicates pain in 1 or more muscles.


n: a small cell often associated with adult periodontitis in deep periodontal pockets. It characteristically lacks a cell wall.


adj: a clinical situation where fungus has been attributed to an established infection or lesion.

mylohyoid concavity

n: a fossa found in the molar region of the mandible that is inferior to the mylohyoid line.

mylohyoid groove or canal

n: groove (indentation) on the medial surface of the ramus of the mandible beginning at the lingula; it houses the mylohyoid artery and nerve.

mylohyoid region

n: an obsolete term that refers to the area on the lingual surface of the mandible that contains the mylohyoid ridge and the attachment of the mylohyoid muscle. It is part of the alveololingual sulcus.

mylohyoid ridge

n: where the mylohyoid muscle originates and attaches on the medial aspect of the body of the mandible. It forms the floor of the mouth.

myofascial pain dysfunction syndrome

n: a collection of medical and dental conditions represented by chronic pain with numerous myofascial trigger points (knots) and fascial constrictions. Characteristic traits of a myofascial trigger points include focal point tenderness, reproduction of pain upon trigger- point palpation, hardening of the muscle upon trigger point palpation, pseudo-weakness of the involved muscle, referred pain, and limited range of motion following continuous trigger-point pressure. The temporomandibular joint and/or muscles of mastication and related tissues can be affected.

myogenous pain

n: deep somatic musculoskeletal pain initiating in skeletal muscles, fascial sheaths, or tendons. Myogenous pain associated with temporomandibular disorders (TMDs) has usually been connected to hyperactivity or abnormal contraction of masticatory muscles.


n: a digital electronic pulse generator expressly designed to provide a bilateral transcutaneous electrical neural stimulus for the stomatognathic system. Developed as a means of applying electrical stimulation for the purpose of providing muscle relaxation as a prerequisite to obtaining an occlusal position and records.


n: swelling or inflammation of muscle tissue induced by the immune system, injury, or infection.

myostatic contracture

n: shortening of a muscle resulting from a lack of nerve stimulation and movement.


n: a neuromuscular condition that demonstrates increased muscle irritability and contractility accompanied by an impaired ability of the muscle to relax.


Nasal grimace

n: an oronasal compensatory movement of the tissues of the nares that occurs in response to palatopharyngeal insufficiency.

nasal prosthesis

n: a prosthesis inserted into the nose to restore those parts of the nose lost due to trauma, amputation, cancer, or burns.

nasal septal prosthesis

n: a prosthesis inserted into the nose to occlude or plug a perforation or hole within the nasal septum; also known as a nasal septal button or plug.

nasal spine

n: the forward prolongation of the left and right maxillae forming a sharp bony extension at the inferior margin of the anterior aperture of the nares.

nasal stent

airflow through the nasal passages and to reduce snoring.

nasal turbulence

n: air that is forced through a small opening in the nasal passages causing movement of secretions above the opening resulting in a rustling- like noise.


n: the quality of speech sounds when the sounds are produced as a result of the nasal cavity being used as a resonator.


n: on the human skull, it is the point at which the midsagittal plane bisects the intersection between the nasal bones and the frontal bone. It is used as a landmark on cephalometric radiographs.


n: the portion of the pharynx that is superior to the soft palate.

Natural Color System

n: six elementary colors are the basis for the Natural Color System: white, black, yellow, red, blue, and green. The system uses percentages of individual component colors to determine nuances.


n: the death of cells by unprogrammed methods as opposed to apoptosis, which is a programmed death. Pyknosis (shrunken and hyperkeratosis or darkened basophilic nuclear staining), karyolysis (swollen and pale basophilic nuclear staining), and karyorrhexis (nuclear rupture or fragmentation) are typical events in necrosis of cells. The release of intracellular contents leads to an inflammatory response.

necrotizing ulcerative periodontitis

n: see under periodontitis.

nerve fiber

n: see under fiber.


n: inflammation of the nerve(s).

neurogenic pain

n: pain caused by abnormalities in the structure of nerves that innervate affected areas. Pain can occur with nociception. The pain is frequently described as burning or sharp. A sensation may occur along the pathway of the nerve. While the patient may locate the pain, the apparent area may not be the source, and the severity of the pain is usually more intense than expected given the degree of stimulation.


n: an assortment of neuronal pathological conditions that occur as a consequence of trauma, infections, metabolic disorders, or exposure to toxins that induce injury to the nerve axons of the peripheral nervous system. Neuropathy typically induces pain and numbness in the affected area.

neutral zone

n: the potential intraoral space where denture teeth should be preferably located, so the function of the musculature will not unseat the denture and forces generated by the tongue are counterbalanced by the forces produced by the lips and cheeks.

nickel-chromium alloy

n: dental casting alloys made primarily of nickel 70% and chromium 30% with trace amounts of molybdenum, manganese, silicon, carbon, and aluminum. The greater the nickel content, the more ductile the alloy; however, its strength, hardness, modulus of elasticity, and fusion temperature are adversely affected. Chromium, by its passivation effect, ensures corrosion resistance of the alloy.


n: (1) a central point or focus where a morbid process begins; (2) nucleus or center.

night guard

n: see occlusal guard.

noble metal

n: a metal consisting of elements that resist oxidation and corrosion in a moist or humid environment; see also base metal.

noble metal alloy

n: a dental casting material that consists of gold, palladium, and silver with lesser amounts of iridium, ruthenium, and platinum. These metal alloys are used for inlays, onlays, complete metal crowns, and backings for ceramic baking.


adj: caused by or responding to a painful stimulus.

nociceptive pathway

n: an afferent neural path (conduit) initiating at a peripheral site in the body and ending in the central nervous system’s somatosensory cortex where the original peripheral stimulus is perceived as pain.


n: a sensory receptor that is activated by noxious stimuli.


n: a small solid mass of tissue collection; a knot or aggregation of cells that can be easily felt by touch.

nonadjustable articulator

n: an articulator that has limited hinge opening and closing arcs about a fixed axis. Casts are arbitrarily mounted without use of a facebow. The maximum intercuspal position is the only reproducible position using this type of articulator. It does not allow for adjustments to duplicate mandibular movements. See also cast relator.

nonanatomic teeth

n: artificial teeth with occlusal surfaces that are not anatomically correct. These teeth are designed in accordance with mechanical principles and are not intended for anatomic duplication. See also zero-degree teeth.

nonarcon articulator

n: an articulator with the equivalent condylar guidance compartment attached to the lower member and the condyle equivalent hinge axis compartment attached to the upper member.

nonfunctional side

n: the side of the arch located contralaterally to the functional side, which the mandible moves away from during lateral excursive movement.

nonrigid connector

n: a connector that allows a limited movement between the retainer and the pontic components of a fixed partial denture. Its usage is indicated in cases where a single path of insertion cannot be achieved due to nonparalleled abutments.



(occluded; occluding) v: (1) to close or bring together; (2) to bring the teeth together in alignment for chewing.


n: a type of articulator.

occluding jaw record

n: a registration record of maximum intercuspation.


adj: pertaining to the contacting surfaces of opposing maxillary and mandibular posterior teeth, prostheses, or prosthetic baseplates with their associated wax rims.

occlusal adjustment

n: any adjustment (reshaping, selective grinding) to the occluding surfaces of teeth or restorations intended to change or improve the manner in which opposing teeth fit together as in their occlusion.

occlusal embrasure

n: the interdental space located coronally to the contact area.

occlusal force

n: force applied to opposing teeth that results from contraction of the muscles of mastication; the force created during mastication via the action of muscles.

occlusal form

n: the shape on the chewing surfaces of a tooth or a row of teeth.

occlusal guard

(bite guard, mouth guard, night guard) n: a plastic removable dental appliance that covers a dental arch separating opposing teeth from each other so that teeth cannot damage each other during parafunctional activity.

occlusal pivot

n: a raised area placed on the occlusal surface of a tooth (usually on a molar) that acts as a fulcrum and limits mandibular full closure, thereby inducing rotation of the lower jaw.

occlusal plane

n: (1) an imaginary plane formed by the incisal edges of the anterior teeth and the occlusal cusps of the posterior teeth. The plane represents the curvature formed by these edges. (2) The surface of wax occlusal rims used for removable partial and complete dentures that simulates the incisal edges of the anterior teeth and the occlusal cusps of the posterior teeth. (3) A flat or curved guide for making dental prostheses that is used to position the incisal edges of the anterior teeth and the occlusal cusps of the posterior teeth.

occlusal pressure

n: force applied to the occlusal surfaces of teeth.

occlusal reduction

n: the amount (in millimeters) of tooth structure removed from the occlusal surface of teeth in order to provide adequate interdental space for a restorative material.

occlusal reshaping

n: the act of physical recontouring the occlusal surfaces of teeth.

occlusal surface

n: the anatomic masticatory surfaces of posterior teeth as outlined by the mesial and distal marginal ridges and the buccal and lingual cusp eminences.

occlusal vertical dimension

n: a vertical measurement of the relationship of the maxilla and mandible when the existing teeth are in maximum intercuspation. See also vertical dimension.

occlusal wear

n: the loss of tooth structure caused by attrition or abrasion due to functional and parafunctional contact of opposing teeth.


n: closure of maxillary and mandibular teeth together in a static position.

occlusion analysis

n: a study of a patient’s masticatory system of a patient that evaluates how the teeth come together in functional and parafunctional activities. The goal is to discover how all aspects of the system, including teeth, jaws, muscles of mastication, and joints, work together to create either a healthy physiologic occlusion or an unhealthy disease- producing occlusion.

occlusion record

n: a record of the relationship of the maxilla and the mandible as they occlude in any position.

occlusion rim

n: a surface that attaches to a denture base that can be used to record the occluding relationship between the maxilla and the mandible and that may facilitate the arrangement of denture teeth as a step toward the creation of a denture.


n: a condition in which fewer than a complete set of teeth are formed; oftentimes the teeth that are present may be smaller than normal

onlay graft

n: a method of attempting to add de novo bone to the height or width or other dimension of an existing bony structure, for example, onto the alveolar ridge, by adding autologous or another form of bone or bone-forming substitute subperiosteally onto the native bone.


n: a condition characterized by imperviousness to light.


n: a material that does not allow light to pass through; not transparent or translucent.

open bite

n: lack of contact between opposing teeth in centric occlusion.

opening movement

n: the change in position of the mandible as the maxillary and mandibular jaws separate upon opening.

open occlusal relationship

n: lack of contact between opposing teeth in centric occlusion.

opportunistic infection

n: an infection that develops in an immune compromised patient that is caused by endogenous, normally nonpathogenic, flora.

oral flora

n: the microbiota of the oral cavity.

oral mucosa

n: keratinized and nonkeratinized mucosa that lines the oral cavity.

oral orifice

n: the opening of the oral cavity through the face.

oral sepsis

n: infection of oral origin that causes systemic toxicity.

orbital prosthesis:

prosthesis to replace the orbital contents and/or adjacent structures

oroantral fistula

n: see under fistula.

orofacial fistula

n: see under fistula.

oronasal fistula

n: see under fistula.


n: the portion of the pharynx that lies between the upper edge of the epiglottis and the soft palate.

orthodontic ligature

n: see ligature.


adj: having a straight profile, neither a protruding or a receding jaw profile.


n: a panoramic radiograph.

orthopedic craniofacial prosthesis

n: an active maxillofacial appliance used to preserve or position the craniofacial osseous sections that are misaligned due to trauma or craniofacial anomalies.

orthotic device

n: in dentistry, a bite plate used in treatment of temporomandibular disorders.

osseointegrated implant

n: see under implant, oral.


n: the osseous contact to the surface of a dental implant. Much of the contact is formed by osseous cellular hemidesmosomes. Macroscopically, the osseous formation engages the microscopically rough surface of the dental implant much like a Velcro connection, thereby making movement of the implant unlikely without a large dislodging force. Titanium dioxide is biological molecular surface that is engaged by the osseous cells.


adj: bony

osseous coagulum

n: the combination of bone fragments or elements and a blood clot.


n: process of becoming bone or transforming into bone; woven bone to lamellar bone.

ossifying fibroma

n: see fibroma.


n: the surgical use of rotary or osteotomes to form a receptor site for placement of an implant; to reshape bone form to achieve a better or more natural contour.


n: removal of bone or a portion of bone, usually with rotary instrumentation using a diamond or steel bur to reshape or recontour bone to conform to better bone health by itself or around the neck of a tooth.


n: inflammation of bone that may cause resorption or deformation of bone conducive to bone health. May result in higher density of bone or destruction of bone in the same area depending on the pH of the area when osteitis is causing destruction.


n: usually associated with chronic degeneration of cartilage, fibrous connective tissue, and/or bone tissue associated with joint components; usually associated with pain or limited movement of the associated joint and capsule surround the joint.


n: a specialized terminally differentiated cell developed from the mesenchymal stem cell lineage. They have single nuclei and are responsible for synthesizing dense cross-linked collagen and other specialized proteins, such as osteocalcin and osteopontin. When organized into groups of connected cells, they also produce a calcium- and phosphate-based mineral that is deposited, in a highly synchronized manner, into the organic matrix of bone. Individual osteoblasts cannot generate bone. The combination of connected osteoblasts and the produced bone is called an osteon.


n: a large multinucleated cell that is derived from macrophages. Osteoclasts release cathepsin K, which breaks down the proximal bone mineral matrix, thereby allowing the release of bone morphogenetic proteins that induce osteoblasts to deposit new bone mineral matrix.


n: a once-functional osteoblast that has become embedded within the bone mineral matrix and is responsible for controlling bone metabolism.


n: formation or creation of bone.


n: any tissue or material that has the ability to induce growth or repair of bone.


n: the premature organic matrix of bone; bone that is in the developmental stage but has not undergone calcification.


n: chemicals, procedures, or materials that have the ability to induce bone formation (osteogenesis) through the recruitment and/or differentiation of osteoblast precursor stem cells and/or recruitment of mature osteoblasts to the area needing bone growth or repair.


n: infection of bone that is usually caused by bacteria. A long-term infection can lead to bone destruction.


n: relating to bone and the periosteum that covers it.


n: removal or reshaping of the alveolar process with rotary instruments, piezoelectric technology, or hand instruments to accomplish a more physiologic form without removing alveolar bone proper.


n: skeleton pathology distinguished by decreased normal bone mass and mineralized bone density; it is seen most commonly in the elderly.


n: the death of most or all of the bone cells due to irradiation.


n: a beveled chisel for use in cutting or preparing bone.


n: the intended or desired cutting of a bone; often used to describe the tasks of smoothing, leveling, realigning, or altering external contours of the bone.


n: a nonfixed dental prosthesis that sets upon and/or is retained in position by 1 or more teeth and/or dental implants; also known as an overlay denture, overlay prosthesis, or superimposed prosthesis.


Palatal incompetence

n: the muscular inability of the soft palate to adequately seal the port between the nasopharynx and the oropharynx during speech and swallowing. Failure to seal this port results in unintelligible speech and nasopharyngeal regurgitation of food and liquids. Conditions that cause palatal incompetence include degenerative nerve diseases, tumors, myasthenia gravis, strokes, cleft palate, polio, cerebral palsy, muscular dystrophy, and araxia. Also known as palatopharyngeal incompetence.

palatal vault

n: (1) the most superior and deepest portion of the palate; (2) the palatal curvature.


n: a record of the movement of the tongue and soft palate created during function, usually speech.

palatopharyngeal incompetence

n: dysfunction of an anatomically intact soft palate resulting in inadequate palatopharyngeal closure. Palatopharyngeal incompetence is usually a result of neurologic or muscular disease or trauma.

palatopharyngeal sphincter

n: the muscular ring that controls separation of the nasopharynx and oropharynx during swallowing and speech.


n: surgical reconstruction of a cleft palate.


v: to alleviate symptoms or afford relief from a disease or medical condition.


adj: providing relief without effecting a cure.


(palpated; palpating) v: to examine by manipulation or touch—palpation.


n: a significant reduction in blood cells and platelets in circulation.

panoramic radiography

n: a process of radiography made on a single film by a continuous circumferential radiographic exposure of the maxillary and/or mandibular dental arches.


(pl papillae) n: a small, nipple-shaped elevation.

  • circumvallate papilla: one of 8 or 10 protuberances from the dorsum of the tongue making a V-shaped row anterior to and parallel with the sulcus terminalis. A circular trench having a slightly raised outer wall surrounds each papilla. On the borders of the papilla and on the opposed margins of the vellum are several taste buds.
  • filiform papilla: extended conical protuberances covering the dorsum of the tongue.
  • foliate papilla: several parallel protuberances arranged in transverse folds on the posterolateral margins of the tongue.
  • fungiform papilla: several, small, mushroom-like elevations formed on the dorsum of the tongue.
  • incisive papilla: an elevation in the soft tissue that conceals the foramen of the incisive or nasopalatine canal.


n: a benign epithelial, exophytic, pedunculated, cauliflower-like neoplasm. Viral etiology may be the causative agent.


n: a small, superficial, circumscribed, hard elevation of the skin that does not contain pus.


n: abnormal or disordered function, as in bruxism, clenching, or rocking of teeth when using teeth as tools.


n: morbid or perverted normal sensation, such as tingling or burning. The abnormal sensation is usually caused by injury to a nerve and is sometimes a complication after surgical procedures. Also known as paresthesia.

partial dislocation

n: a condition of the temporomandibular joint characterized by a displaced articular disc and partial displacement of the condylar head from its normal, healthy, resting position. As a result of these pathologic changes, the joint function is disrupted either unilaterally or bilaterally to varying degrees.


n: a drainage tract seen in attached and/or mucosal ginigiva that is associated with an oral abscess of odontogenic origin. Commonly known as gum boil.


adj: (1) latent, not active; inert; (2) resistant to corrosion.

passive eruption

n: see under eruption, dental.


adj: open, not obstructed: the specific unobstructed route in which a removable dental prosthesis (or the precementation stage of a fixed dental prosthesis) may be removed.


n: any microorganism that is disease producing.


n: the mechanism that causes a given disease.

pathogenic occlusion

n: an abnormal occlusal relationship with the potential to produce pathologic changes in the masticatory system.


n: a specific characteristic or symptom of a disease that predictably leads to the diagnosis of the disease.


n: the current state of being with disease.


n: a narrow base resembling a stalk or stem that connects tissues (eg, vertebrae) to each other; forms the base of tumors; in dentistry, pedicles are used in grafting procedures. See also pedicle graft.

pedicle graft

n: a flap of skin in which viability is maintained by a vascularized donor stem. In dentistry, these flaps, while still attached at one end, are used to cover exposed root surfaces.

peg lateral

n: a permanent maxillary lateral incisor that is tapered and small. Commonly referred to as a baby tooth or baby teeth.


adj: allowing for the passage of light without distortion; transparent.


n: a rare autoimmune disease that is characterized by skin rashes and blistering on the arms, legs, abdomen, eyes, mouth, nose, and vagina.


n: a general term referring to a group of autoimmune diseases that primarily affect the elderly and result in severe, deep blistering of the skin and mucous membranes.

Peptostreptococcus spp

n: anaerobic, gram-positive cocci that infect the body including soft tissues. In dentistry, these organisms can invade the subgingival flora leading to infection and slow recovery times.

perceived color

n: description of color based on various attributes (eg, names of colors) or based on the senses (eg, smell, touch, sound).


n: to strike objects to produce a sound; in dentistry, tapping with fingers or with a medical device on oral structures can allow for diagnoses regarding the state of inflammation, disease onset, or progression or healing.


adj: of or relating to tissues that surround the apex or root (root tip) of a tooth; may include the periodontal ligament or alveolar bone.

pericoronal abscess

n: a pus-producing lesion that forms above the crown of a partially erupted tooth.


n: inflammation of the soft tissues that surround an osseointegrated implant that presents with bone loss.

peri-implant mucositis

n: inflammation of the mucosa that surrounds an osseointegrated implant that has no bone loss.


n: erosion of the teeth due to chronic gastric regurgitation of stomach acid.


adj: pertaining to or occurring around a tooth.

periodontal abscess

n: pus-producing infection of any periodontal tissue that usually involves the bone and soft tissue surrounding a tooth.

periodontal fiber

n: see under fiber.

periodontal intrabony pocket

n: a periodontal pocket distinguished by its extension into an intrabony periodontal defect.


n: pain associated with the periodontal structures.


n: inflammation of the supportive tissues of the teeth that is a progressively destructive disease leading to the loss of associated bone and periodontal ligament support. A progression of inflammation from the surrounding gingiva into the bone and ligament that supports the affected tooth or teeth.

  • adult periodontitis: a rarely used term. In general, patients previously classified as having adult periodontitis are now included under the chronic periodontitis category.
  • aggressive periodontitis: a specific type of periodontitis with unmistakably identifiable clinical and laboratory findings that make it sufficiently different from chronic periodontitis so as to warrant a separate classification. Aggressive periodontitis occurs in patients who are otherwise clinical healthy (except for periodontal disease). Usual features include rapid attachment loss and bone destruction. Patients with aggressive periodontitis generally exhibit amounts of microbial plaque that are inconsistent with the severity of periodontal destruction, phagocyte abnormalities, and increased levels of Aggregatibacter actinomycetemcomitans and possibly Porphyromonas gingivalis. The generalized form of aggressive periodontitis was formerly referred to as generalized juvenile periodontitis, Aggressive periodontitis usually affects persons younger than 30 years but patients may be older. Normally, there is widespread interproximal attachment loss affecting at least 3 teeth other than first molars and incisors, and there is a well-defined intermittent nature regarding the destruction of attachment and alveolar bone. The serum antibody response may be lacking or insufficient in response to the infecting agents. Aggressive periodontitis localized form was formerly termed localized juvenile periodontitis. It has many of the common features of aggressive periodontitis generalized form but the onset occurs at puberty. Localized first molar/incisor involvement with interproximal attachment loss has been associated with a first molar and/or and incisor and not more than 2 other teeth. Differing from agggressive periodontitis generalized form, the localized form typically demonstrates a vigorous serum antibody response to infecting agents.
  • chronic periodontitis: an infectious disease that presents with inflammation within the supporting tissues of the teeth. Progressive attachment and bone loss are accompanied by pocket formation and/or recession of the gingiva. Chronic periodontitis is the most frequently occurring form of periodontitis. It is found most often in adults but can also occur in young patients. Plaque and calculus accompany chronic periodontitis. The sequence of attachment loss is typically slow; however, periods of fast development may occur. The microbial configuration is not consistent or predictable.
  • early-onset periodontitis: a previously used term. See aggressive periodontitis.
  • juvenile periodontitis: See aggressive periodontitis.
  • necrotizing ulcerative periodontitis: an infection characterized by necrosis of gingival tissues, periodontal ligament, and alveolar bone. These lesions are often associated with systemic conditions: malnutrition, human immunodeficiency virus infection, and immunosuppression.
  • prepubertal periodontitis: a term rarely used to designate the preadolescent existence of periodontitis. These patients are now incorporated under the chronic periodontitis category or the periodontitis associated with systemic diseases category.
  • rapidly progressive periodontitis: a previously used term. See chronic periodontitis and agressive periodontitis.
  • recurrent periodontitis: a condition where periodontitis recurs after having been treated successfully. It is an additional adjective to further describe an existing category of periodontitis, such as recurrent aggressive periodontitis or recurrent chronic periodontitis.
  • refractory periodontitis: a disorder where 1 or more treated forms of periodontitis have not responded to the appropriate treatment. It is an additional adjective to further describe an existing category of periodontitis, such as refractory aggressive periodontitis or refractory chronic periodontitis.


n: the gingiva, alveolar mucosa, cementum, periodontal ligament, and alveolar bone tissues that surround and support the teeth.


n: the scientific study of periodontal tissues in health and disease.


n: a method for measuring tooth mobility.


n: agents that induce and/or initiate periodontal pathology.


n: an inflammatory process involving the periosteum.


(pl, periostea) n: the outer membrane of dense irregular connective tissue that covers all bones except the joints of long bones. The osteoblasts and osteoclasts in this membrane are responsible for the resorptive and additive potential of the bones that it invests. It also contains nociceptive and circulatory elements.


adj: pertaining to the tissues immediately adjacent to a tooth root, often described radiologically or histologically, but it can also be a clinical descriptor.


n: an inflammatory process at the corners of the mouth. More commonly known as angular cheilitis. Often caused by fungal or bacterial infection and can be concomitant with decreased occlusal vertical dimension.

permanent dentition

n: the adult or second set of teeth that remain after childhood.


n: red or purple purpuric eruptions measuring <3 mm in diameter each, occurring from minor hemorrhage of skin or mucous membrane.


n: inflammatory cells capable of ingesting foreign or dead cell matter for elimination.


n: the functional process of a phagocyte.

pharyngeal walls

n: boundaries of the nasopharynx and oropharynx.


(pl, pharynges) n: A funnel-shaped anatomical landmark comprised of musculature that forms a tube that is the pathway for air and food. It is located between the esophagus, nares, and mouth.


n: the physical expression of an individual’s genotype. A compound Greek word formed from the words pheno, which relates to appearance and physical perception, and type, which relates to individual genotype. Phenotype is related to the physical appearance of a subject’s genotype.

physical elasticity of muscle

n: an obsolete term referring to the characteristic of muscle tissue to elongate upon tensile forces.

physical photometer

n: a device that captures and quantifies physical stimuli in lieu of visual stimuli.

physiologically balanced occlusion

n: an obsolete term that refers to occlusion that is in harmony with the neuromuscular system and the temporomandibular joint. It is typically related to maximum intercuspation that coincides with the centric relation position; there are no interferences from posterior teeth during lateral or protrusive movements of the mandible.

physiologic occlusion

n: an obsolete term that refers to occlusion in compliance with the range of motion and function of the masticatory muscles, and temporomandibular joint.

physiologic rest position

n: a mandibular position of relaxation related to the masticatory muscles and is irrelevant to occlusion or position of the teeth. It is the mandibular position where elevator muscles and depressor muscles reach equilibrium. It is characterized by minimal contraction on the antagonistic muscles of the mandible.


n: derived from the compound Greek word physiologia, which is formed from the word physio, which means nature or natural, and logia, which means elaboration or study. As a compound word it relates to the study of the cooperation of the organs (or parts of them) and chemistry that form an organism.


n: a medium or bath used for cleaning, preserving, maintaining, or processing.

pickle (pickled, pickling)

v: to treat, preserve, or clean in or with an agent; as a verb, it refers to the action of preserving, cleaning, maintaining, typically through a medium in liquid.


n: an abutment located between the distal and mesial abutments of a fixed prosthesis.

pier abutment

n: an abutment positioned between adjacent abutments.


n: a branching network; chiefly of nerves, lymphatics, or veins.


n: the furthermost anterior point on the mandible.


n: existing in multiple forms or having numerous morphologic types.

polymorphonuclear leukocyte

n: a type of scavenging white blood cell involved in fighting infections that contains a segmented lobular nucleus and is colorless because of the lack of hemoglobin; eosinophils, basophils, and neutrophils are in this category.


n: an abnormal growth of tissue from the mucous membrane; it has a cylindrical and stalk-like structure.


n: a synthetic rubber used in dental impression materials; it contains chains of sulfur atoms that are anionic or organic in nature.

positional record

n: documentation that uses intraoral and extraoral registrations to capture a specified mandibular position.


adj: located behind; in human anatomy often referred to as caudal; dorsal.

posterior border jaw relation

n: an obsolete term that refers to the border relationship between the maxilla and the most posterior portion of the mandible.

posterior tooth form

n: the morphologic characteristics of the posterior teeth, including the shape of the tooth and its occlusal surfaces.

postmenopausal atrophy

n: deterioration or degradation of tissue, including oral mucosa and bone, that occurs in women after menopause.

postpalatal seal area

n: area of the soft palate located beyond the junction of the hard and soft palate that should be compressed within physiological limits by the post dam part of the maxillary conventional complete denture to achieve an adequate peripheral seal and denture retention.

postsurgical maxillary prosthesis

n: a maxillofacial prosthesis constructed to correct the intraoral/extraoral defect resulting from maxillary resection due to a tumor or reconstruction of acquired or congenital defects of the maxilla to improve esthetics and function.

postural contraction

n: the minimal muscular contraction required to maintain mandibular posture.

postural position

n: any mandibular position occurring during minimal muscular contraction.

pre-angled abutement 1 piece

n: the 1-piece stock dental implant abutment that has a preset angle to the long axis of the implant fixture.

pre-angled abutement 2 piece

n: it is a 2-piece stock dental implant abutment that has a preset angle to the long axis of the implant fixture.

pre-ceramic solder

n: a soldering procedure of the metal framework of a metal-ceramic prosthesis before ceramic buildup at a temperature of 1075°C to 1120°C.

precious metal

n: naturally occurring rare metallic element with a set of physical and chemical properties unrivaled by many other materials. It is less chemically reactive than most elements, e.g., gold, platinum, osmium, iridium, palladium, ruthenium, rhodium, and silver.

precious metal alloy

n: a mixture of metals that contains a precious metal, for example, gold, platinum, osmium, iridium, palladium, ruthenium, rhodium, and silver.

precision attachment

n: a mechanical retainer consisting of male (patrix) and female (matrix) pieces that are closely fitting and use a frictional force to attach fixed or removable partial dentures to the crown of an abutment tooth or a restoration.

preliminary cast

n: a model produced from a preliminary impression for use as a diagnostic tool or special tray construction.

preliminary impression

n: a negative likeness constructed using a stock tray, the cast produced from this impression is mainly used in diagnosis, treatment planning, or special tray construction.


n: the tension created in an implant abutment screw in consequence to torquing the screw.

preoperative wax-up

n: a simulation of the clinical and dental laboratory procedures planned for achieving the desired esthetics and function for the patient’s prosthesis using dental wax on mounted diagnostic casts.

preprosthetic surgery

n: the surgical interventions implemented before prosthodontics treatment to improve the anatomy and/or contour of the residual alveolar ridge and/or its surrounding areas to improve the prognosis of the prosthodontic treatment.

prepubertal periodontitis

n: see under periodontitis.

pressure area

n: a region of the denture supporting area that is subjected to more pressure than other supporting areas from a dental prosthesis.

pressure indicating paste

n: a material injected or spread on the intaglio surface of the denture to determine the pressure area on the supporting tissue of a dental prosthesis.

pressure relief

n: an obsolete term referring to the alteration of the intaglio surface of the denture to eliminate the pressure area of the denture-supporting tissue.

primary pain

n: pain proximately associated with a noxious stimulus versus referred pain, which is nonproximate.


n: a slender instrument, often calibrated, that is used to explore or measure a wound, body cavity, passage, or periodontal pocket.

probing depth

n: the distance measured from an established reference point to the tip of the periodontal probe.


n: (1) a bony projection or prominence; (2) any technical procedure that involves multiple steps; (3) the procedure to polymerize dental resin in the production of dental prostheses or bases.

processed denture base

n: a heat polymerized, dense, color-stable acrylic foundation that attaches to artificial teeth.


n: an early symptom indicating the onset of a disease or condition.


n: an outline image of an object or structure as viewed from the side.

profile record

n: a record or registration of a patient facial profile.

progenitor cell

n: an undifferentiated cell that can differentiate into a specialized cell; also called a stem cell.


n: a protruded position of the maxilla and/ or mandible in relation to the face;


adj: a forward relationship of the jaws, usually used with reference to the mandible.


n: the condition of a protruded position of the maxilla and/or mandible in relation to the face.

progressive loading

n: the gradual applications of force on a dental implant either deliberately, as done through a dental prosthesis, or inadvertently, from forces placed by anatomic structures or parafunction.

progressive mandibular lateral translation

n: the lateral positional change of the mandible as the nonworking condyle translates along the articular eminence.

progressive systemic sclerosis

n: a progressive autoimmune disorder resulting in overproduction of abnormal collagen leading to sclerosis and fibrosis of the skin and internal organs. Oral structures become stiff and indurated leading to a reduction of oral cavity access. The periodontal ligament spaces may appear enlarged on a radiograph. Also called systemic scleroderma.

projected pain

n: the sensation of pain at an area remote from the site of origin.

prophylaxis, oral

n: the art and science of preventing gingivitis through the removal of bacterial plaque, material alba, calculus, and extrinsic stain from the teeth and roots performed by a dentist or hygienist. Also called a prophy.

proportional limit

n: the measurement of stresses that is the point beyond which deformation is not directly proportional to the load being applied.


n: the reception of sensory nerve terminal signals that provide information pertinent to movements and the position of the body; awareness mediated by signals from proprioceptors.


n: sensory nerve terminals that mediate signals related to movement and position of the body and its parts.


n: a family of fatty acids, unsaturated carboxylic acids, generated by arachidonic acid metabolism via the cyclooxygenase pathway. They are produced by most cells and are potent regulators of a number of biological processes. Their production is inhibited by aspirin, ibuprofen, and other inhibitors of cyclooxygenase.


(pl, prostheses) n: (1) a fabricated, artificial replacement of a missing part of the human body; (2) a device to improve or alter the function of a damaged or missing body part; (3) a device used to help achieve a desired surgical outcome.

  • dental prosthesis: replacement of a missing part of the natural dentition or oral cavity by an artificial device; fixed partial denture. See also denture.
  • temporary prosthesis: a fixed or removable restoration that is fabricated to be eventually replaced with a more permanent device.


adj: concerning artificial prosthetics or a prosthesis.


adv: concerning artificial prosthetics or a prosthesis.


n: (1) pertaining to mandibular jaw bone relationships: — projection of the mandible anterior to the position of centric relation; (2) pertaining to teeth or jaw bones — the projection of teeth or bony structures anterior to the normal standard.


adj: forcing forward; adjective signifying protrusion; the forward or thrusting movement of the mandible.

protrusive deflection

n: the displacement of the mandible from the midline during the protrusive movement of the mandible; the symptomatic restriction of mandibular movement.

protrusive deviation

n: the amount of protrusive deflection during the protrusive movement of the mandible. Protrusive deviation indicates interference during movement.

protrusive interocclusal record

n: a registration of the mandibular movement relative to the maxilla during forward movement of the condyles in the temporal fossa.

protrusive jaw relation

n: an obsolete term referring to the relationship of the mandible to the maxilla that results from the protrusion of the mandible.

protrusive movement

n: the movement of the mandible anterior to centric relation.

protrusive occlusion

n: an obsolete term referring to an occlusion that results when the mandible is advanced anterior to centric maximum intercuspation.

provisional cementation

n: the cementation of an interim or final restoration with a weak luting agent such that the restoration can be easily removed at a future date

provisional splint

n: an interim device that stabilizes mobile teeth during diagnostic or therapeutic procedures. Also known as an interim splint.


adj: (1) nearest or adjacent to the reference point; (2) situated near a point of origin, the midline or attachment; (3) in dentistry the tooth surface adjacent to another tooth.


n: a thin, adherent, gray-white exudative layer that forms over mucosa. It appears as a false membrane and is composed of necrotic cells, debris, and bacteria. Pseudomembranes are seen in necrotizing ulcerative periodontitis.


n: a periodontal pocket that forms as a result of tissue hypertrophy rather than as a result of recession and apical migration of the junctional epithelium. See also periodontal intrabony pocket.

  • pseudopocket space: the gingival crevice containing the periodontal ligament.
  • pseudopocket syndrome: a collection of symptoms and clinical signs characteristic of periodontal diseases such as inflammation, loss of the gingiva, tooth mobility, etc.
  • pseudopocket traumatism: see occlusal traumatism.
  • suprabony pocket: a periodontal pocket with its deepest point coronal to the alveolar bone.


adj: a term referring to the relationship between physical stimuli and the sensory perception of physical stimuli.

psychophysical color

n: a measurement of color stimuli by scientifically defined values, such as 3 tri-stimulus coordinates.


n: richly vascularized and innervated connective tissue found at the inner core of a tooth called the pulp cavity. The pulp is divided into the coronal aspect (coronal pulp) and root aspect (radicular pulp).

pulp capping

v: the placement of a material or medicament to serve as a barrier to protect the pulp and promote healing of the pulp tissues. Pulp capping is accomplished either directly or indirectly.


n: complete extirpation of the coronal and radicular pulp.


n: a state of inflammation of the dental pulp that can be reversible or nonreversible.


n: complete removal of the coronal portion of the dental pulp as a means to stop the pain of a pulpitis emanating from inflamed coronal pulp tissue or as a means to allow viable radicular pulp tissue to continue to form the root of a blunderbuss apex unaffected by the irreversible pulpitis of the coronal tissue.

pulp vitality tests

n: tests used to determine whether the pulp of a tooth is without vitality, inflamed, or within normal limits of health. The different tests include electrical stimulation, thermal stimulation, or the more invasive cutting into dentin with a burr to determine sensitivity.


n: sandlike volcanic glass that is used as a polishing agent in dentistry. Different sized particles proceeding from coarser to finer are used to progressively smooth a hard surface. Materials polished may include natural tooth structure, acrylic, and other restorative materials.


(pumiced pumicing) v: to polish the surface of a tooth or restoration with pumice.


adj: in the state of being infiltrated, filled, or releasing pus.


n: a generally viscous, yellowish-white fluid formed in infected and inflamed tissue consisting of white blood cells, cellular debris, necrotic tissue, and bacteria.


n: a reaction of tissue to infection that results in a small superficial elevation caused by the collection of pus under the skin.


adj: pus-producing.


n: a description of periodontal disease not in common use in today’s vernacular.

pyramidal fracture

n: a complex of fractures of the midfacial bones involving the upper jawbone. The main fracture lines meet above the nasal bones and form a triangular section detached from the skull. Referred to as the La Forte II fracture.



n: the second most abundant mineral in the earth’s continental crust. It is an extremely hard material made up of a continuous framework of SiO4.



radiation absorbed dose, a unit of absorbed dose of ionizing radiation equivalent to an energy of 100 ergs per gram of irradiated material.


n: in dentistry, usually refers to ionizing radiation. The energy that comes from a source of unstable atoms, which have excess energy, is then passed through tissue, producing charged particles called ions. These unstable ions are radioactive and become stable by release of energy, which can be in the form of electromagnetic radiation, such as X-rays, or particulate rays, such as gamma rays.

radiation shield

n: a prosthesis used during radiation treatment that serves to protect or shield adjacent areas of tissue not meant to be radiated from orthovoltage during treatment of malignant lesions of the head and neck area. Also known as a radiation positioner.

radiation source prosthesis

n: a prosthesis made for a specific patient to aid in the trajectory and targeting of radiation to an anatomic site in order to treat a tumor at that site.


adj: describing the root component of a tooth.


n: an image generated on a sensitive surface (sensor) by a form of radiation other than visible light, specifically, an X-ray or gamma ray picture.


v: to produce a radiographic image of a hard tissue structure usually composed of varying densities.


adj: having properties such that roentgen rays and radiant energy are minimally absorbed; radiographic film appears darker representing radiolucent areas due to the less effective absorption of such energy.


adj: having properties such that roentgen rays or other forms of radiant energy are absorbed more readily leading to less pass-through of such energy rays; on exposed radiographic film such areas appear lighter or whiter on the exposed negative film.

ramus endosteal implant

n: a dental implant that is inserted at least partially into the ramus of the mandible.

ramus frame endosteal implant

n: a dental implant design comprising a horizontal intraoral supragingival bar-shaped abutment and bilateral posterior endosseous segments that pass through the soft tissues and enter the ramus on each side of the mandible. An anterior segment also passes through the soft tissue covering the symphysis and enters the symphyseal bone. These implants are typically constructed from one piece of metal, although 2 or 5 endosteal sectional implant segments can be placed and connected with fitted parts after placement of the individual segments. See also implant, oral.

range of motion

n: a measurement of the degree to which a joint may be extended or flexed. A measurement describing the degree to which the temporomandibular joint may move as in opening or demonstrating lateral or protrusive excursions.


n: (1) an area marking the line of union; (2) A fibrous area where paired muscles meet.

rapidly progressive periodontitis

n: see under periodontitis.


n: a periodontics term that describes the reconnection of epithelial and/or connective tissues to the surfaces of roots or bone after the connection is disrupted by surgical or other means.


n: a dental laboratory process by which the entire base material of an existing removable prosthesis, but not the teeth, is replaced.

receptor site

n: a reference to a biologic site where molecular binding occurs.

recipient site

n: the receiving area into which a graft or transplant material is placed.


adj: a designed reality in which a force from one part of a prosthetic device is opposed by a different part of the device.

reciprocal click

n: related clicking sounds from the temporomandibular joint, which occur during opening and closing movements.


n: a condition where lateral forces from a retentive clasp moving over the height of the contour of a tooth or crown are opposed by an another (reciprocal) clasp that engages a guiding plane.

recombinant DNA

n: deoxyribonucleic acid (DNA) sequences produced in a laboratory by joining genetic material from multiple sources.


n: retained information that describes facts about something or someone.

record base

n: a denture base that supports material that is used to document the positional correlation of the maxilla to the mandible.

record rim

n: material placed on an interim denture base that may be used to establish and record the positional relationship between the maxilla and mandible; it may also be used to establish the position of teeth. Also known as an occlusal rim.

recurrent periodontitis

n: see under periodontitis.

reduced interarch distance

n: a vertical dimension that allows for overclosure. Compared with the proper relationship, there is a reduced inter-ridge distance when the maxillary and mandibular teeth are in contact and an extreme interocclusal distance when the mandible is at a position of rest. Also known as overclosure.


n: using surgical or manual methods to correct a dislocation or fracture thereby restoring it to its normal anatomic relationship.


n: to reopen a surgical site to observe or alter effects from a prior surgical procedure.

reference plane locator

n: a component of a facebow system used to transfer a reference plane from the patient to an articulator.

referred pain

n: pain that is felt in a site in the body different from the diseased or injured location where the pain would be expected.


n: the measure of the fraction of radiant energy that is reflected from a surface.

refractory cast

n: a cast made of a material that will not deteriorate at the high temperature used in casting removable partial denture frameworks or fixed metal frameworks.

refractory die

n: a die made of a material that will not deteriorate at the high temperatures used during firing or casting procedures.

refractory mold

n: a mold made from refractory material into which metal is cast.

refractory periodontitis

n: see under periodontitis.

refractory prosthodontic patient

n: a patient in whom it is difficult to achieve prosthetic success even when the appropriate prosthesis is provided. The patient may not be able to follow directions or lacks adaptability to prosthodontic treatment.


n: regrowth of lost tissue.

  • guided bone regeneration: refers to alveolar ridge augmentation or bone redevelopment.
  • guided tissue regeneration: techniques for redeveloping (regenerating) lost periodontal tissues.

registration (bite)

n: a record of the occlusal relationship between the maxillary and mandibular jaws.


n: replacement of a tooth into its socket after it is removed surgically or avulsed.

releasing incision

n: an incision made at a right or oblique angle to the main incision to relieve tension on a mucoperiosteal flap and allow more flap reflection than the original incision allows.


n: placement of a measured amount of space in an area under a denture base or removable partial framework to eliminate tissue contact or pressure or to make room for impression material.

relief area

n: a delineated space created on the tissue surface of a removable dental prosthesis to eliminate contact with the tissue.


v: to replace the base material on the tissue side of a removable dental prosthesis with new base material to correct the adaptation of the base to the tissue.


n: the ongoing process by which bone is resorbed and replaced in a dynamic steady-state process that maintains the health of bone.

remount cast

n: a cast made to facilitate remounting the prosthesis on an articulator. Frequently done to refine occlusion.

remount procedure

n: a process in which prostheses are replaced on an articulator after fabrication to refine occlusion.

remount record index

n: a record made on an articulator component to allow remounting of the maxillary cast after processing.


n: excision (removal) of some portion of the jaw, tooth root, or other maxillofacial structure. Typically done for the treatment of pathology.

residual abscess

n: a persistent lesion that remains from a prior infection. It often presents with a radiolucent area.

residual bone

n: fraction of mandibular or maxillary bone that remains after the teeth are removed or lost.

residual ridge

n: the superior portion of the remaining bone with its overlaying soft tissue.

residual ridge crest

n: the most superior portion of the residual ridge.

residual ridge resorption

n: the phenomenon of diminishing volume and density of the residual ridge after the teeth are removed.

resilient attachment

n: a special attachment intended to give a combination tooth- and soft tissue-borne removable dental prosthesis sufficient flexure so as to allow for its placement without introducing unnecessary stress on the abutments.


n: ability of a human, an organism, or an inert material to resist the damaging effects of chemical, microbiological, or mechanical agents.

resistance form

n: features of a tooth preparation that has at least 2 walls approaching parallelism and other walls allowing for thickness of restorative material.


n: (1) in dentistry or medicine: the return to health or improvement of a pathologic state; (2) In digital imaging: a pixel, pel, or picture element that is the smallest recognizable point found in the master image.


n: the progressive loss of soft or hard tissue due to physiologic or pathologic processes.


n: the progressive loss of soft or hard tissue due to physiologic or pathologic processes.

  • bone resorption: bone loss resulting from osteoclastic activity.
  • cavernous resorption: bone loss that leaves a hollow space (decreased bone volume).
  • idiopathic resorption: loss of calcified tissues for no obvious reason.

rest jaw relation

n: an obsolete term for the relationship of the mandible to the maxilla when the patient is in an upright relaxed position and proper physiologic interocclusal distance exists between the teeth as the condyles are resting in the glenoid fossae.


n: any material that replaces lost tooth structure or soft tissue.

rest seat

n: area prepared on a tooth surface or restoration to support vertical or lateral occlusal forces.

rest vertical dimension

n: distance measured between a predetermined point on the maxilla and mandible when the mandible is in physical rest position. One point is on the middle of the face or nose and the other point is on the lower face or chin. See also vertical dimension.


n: device used to stabilize teeth in the desired position; it is usually an orthodontic appliance.


n: (1) in orthodontics, the preservation and stabilization of the teeth in the desired position into which they were moved; (2) in prosthodontics, holding the removable prosthesis in the proper position; (3) in restorative dentistry, capability of a tooth preparation or tooth placement to oppose movement in a vertical or lateral direction.

retention arm

n: extension of metal or plastic arm to add stability to a dental prosthesis.

retention form

n: retention obtained from precise intentional tooth reduction that resists dislodgement of a crown.

retention of the denture

n: an obsolete term that refers to denture retention obtained by utilizing bony undercuts covered with tissue.

reticular fiber

n: see under fiber.


n: instrument used to hold soft tissue away from bony structures in order to visualize an area during surgery or to photograph an area.


n: apical reflection of soft tissue and bone to expose the root tip where a preparation is made and filled with material to seal a root canal.


n: position of the mandible in relationship to the maxilla where the mandible is retruded from its normal position.


n: position of mandible and/or maxilla that is posterior to its normal craniofacial relationship. Typically refers to the mandible.

retromolar pad

n: mass of freely movable, nonkeratinized mucosa tissue located posterior to the retromolar papille of the most distal tooth in the mandible.

retromylohyoid area

n: an obsolete term referring to the area located lingual to retromolar tissue pad extending inferiorly toward the floor of mouth and distally to the retromylohyoid curtain.

retruded contact

n: the contact that occurs during the closure of the mandible in its most retruded path of closure.

retruded contact position

n: the occlusal relationship that occurs when the mandible and the condyles are in their most retruded position. This position may be more retruded than the position referred to as centric relation.


n: movement of the mandible directed posteriorly.


adj: a mandibular position that may be more distal than that described as maximum intercuspation.

reverse articulation

n: positioning of the mandibular teeth that is more buccal than normal relative to the maxillary teeth such that the fossae of the mandibular teeth articulate with the buccal cusp of the maxillary teeth.

reverse articulation teeth

n: artificial teeth that are shaped to allow for the buccal cusp of the maxillary teeth to be arranged in the central fossae of the mandibular teeth.

reverse curve

n: when viewed in the sagittal plane, the occlusal plane position as outlined by the cusp tips and incisal edges of the teeth is curved upward.

reversible hydrocolloid

n: gels that solidify by cooling and return to a flowable state when the temperature is increased.

reversible splint

n: a device used for, or method of, splinting or fixing teeth that does not change or alter the structure of the involved teeth.


n: in dental applications, it refers to a residual dental arch that is a crest of bone covered by soft tissue in its natural state.

ridge augmentation

n: any grafting procedure that increases the lateral and/or vertical dimensions alveolar bone dimensions.

ridge crest

n: the most highly contoured part of an edentulous dental ridge.

ridge lap

n: the tissue approximating portion of an artificial tooth or prosthesis that has been shaped so as to overlap the residual ridge and extends from the buccal to the lingual surfaces.

ridge relationship

n: the position of the mandibular ridge relative to the maxillary ridge.

ridge slope

n: an obsolete term referring to the angulation established by the crest of the mandibular ridge extending from the posterior region toward the anterior area relative to the inferior border of the mandible.

rigid connector

n: part of a removable prosthesis that connects its parts or, in regards to a fixed prosthesis, a portion of the device that connects the retainer to a pontic in such a manner that no movement can occur.

ringless investment technique

n: a method of investing such that no containment is used that may restrict expansion. A paper or plastic cylinder may be used that is less restricting than a metal cylindrical casting ring.

roentgen ray

n: (1) radiation emitted from a tube that results from striking an anode with electrons emitted from a heated cathode; (2) radiation resulting from the excitation of the innermost orbital electron within an atom.


n: the part of a tooth that is typically covered by cementum and is found in the more apical portion. Attached to it is usually a periodontal ligament that allows for connection to the adjacent bone.

  • root concrescence: the fusion of roots of adjacent teeth.
  • root fragment: a part of a tooth that may be retained after an attempt at extraction or that may result from partial resorption of a tooth.
  • root fusion: the connection of roots of a multirooted tooth.
  • root planning: a method of removing contaminated or attached material that may be rough or polluted with toxins or microorganisms.
  • root preparation: the use of chemical or mechanical means to remove contaminants from a root to improve wound healing.
  • root proximity: the distance between adjacent roots.
  • root resection: removal of a portion or all of a tooth’s root.
  • root resorption: loss of part of a root relating to a process that may be idiopathic or may result from tooth movement, trauma, endocrine disorders, inflammation, or neoplastic disease.
  • root retention: preservation of a root, frequently endodontically treated, after the coronal portion has been removed in order to support a prosthesis or preserve the alveolar ridge.
  • root submergence: process of covering a tooth’s root with soft tissue.

root concrescence

n: see under root.

root form endosteal dental implant

n: an implant used in dental applications that is placed into the bone and has some degree of similarity to a natural root. See also implant, oral.

root fracture

n: a fracture, split, or breaks in the otherwise solid part of a tooth that is typically covered by cementum and is found in the more apical portion (root of the tooth).

root fragment

n: see under root.

root rusion

n: see under root.

root planning

n: see under root.

root preparation

n: see under root.

root proximity

n: see under root.

root resection

n: see under root.

root resorption

n: see under root.

root retention

n: see under root.

root submergence

n: see under root.


n: a material made of ferric oxide and binding agents used for polishing and thereby imparting luster to a surface.


abbreviation for the rest, proximal plate, and I-bar, which are the clasp portion of a removable dental prosthesis.


(pl, rugae) n: anatomic ridges of soft tissue that are frequently present on the surface in the anterior portion of the hard palate.



n: one of a series of continuous circles.

scatter radiation

n: any radiation that is not absorbed by the target tissues. This radiation may pass through or be deflected by the tissue. The unabsorbed radiation may then collide with nearby objects or personnel.


n: an induration, thickening, or hardening of a body part, usually induced by a chronic inflammatory reaction or by hyperplasia of interstitial fibrous connective tissue. When found in the jaws it is depicted by an increased calcification as found in condensing osteitis.

screw endosteal dental implant

n: a sterile device that is placed into the jaw bones for the attachment or retention of a tooth or teeth and whose configuration is similar to a screw; it may be hollow or solid, and normally consists of the fixture and the abutment.


adj: relating to or resembling fat or sebum; oily; fatty; discharging fat or a grease-like oil substance.

second-stage dental implant surgery

n: (1) regarding eposteal dental implant surgery, it is the surgical procedure involving placement of an eposteal framework constructed from the first-stage implant surgery impression; (2) regarding endosteal dental implant surgery, it involves the surgical reflection of soft tissue to uncover the superior (tabletop) aspect of the dental implant, the cover screw is removed, and either the healing collar or the interim or definitive dental implant abutment is placed. After this, the relevant tissues are sutured in place as needed.

sectional impression

n: a process of capturing, in segments or parts, any anatomic area using a material that will produce a negative likeness of the area of interest.

sedation, conscious

n: a minimally depressed level of consciousness induced for anxiolysis and fear management that allows the patient to independently maintain an airway and respond appropriately to physical stimulation and verbal commands.

Seibert classification

n: a system of 3 categories used to describe the form of a residual alveolar ridge.

  • Class I defect: loss of tissue width in the facial-lingual or buccal-lingual direction but there is adequate ridge height.
  • Class II defect: loss of ridge height but there is adequate ridge width.
  • Class III defect: loss of both ridge height and width.

Selenomonas sputigena

n: gram-positive, anaerobic, rod-shaped bacteria, mainly from subgingival plaque, that displays a tumbling motility.

self-separating plaster

obs: an impression plaster with the distinguishing characteristic of disintegrating in hot water.

semiadjustable articulator

n: an articulator that allows adjustments to replicate typical mandibular movements. See also Class III articulator.

semiprecious metal alloy

n: an alloy made of both base and precious metals. No specified ratio of components distinguishes 1 group of semiprecious alloys from another group.

separating medium

n: (1) a coating used to keep 1 surface from adhering to a second surface; (2) a material applied on an impression that aids removal of the cast once it has set (hardened).


n: unsafe quantities of pathogenic microorganisms or their products in blood or tissues.


n: systemic disease initiated by the presence of pathological microorganisms or their toxins in the blood.


n: the process whereby necrotic bone separates from native healthy bone and forms a sequestrum.


n: removal of a sequestrum by surgical means.


n: an island of nonvital bone that is separated from native healthy bone.


adj: having a wide base of attachment; lacking a stem; not pedunculated.


n: generally, the sixth part of anything. In dentistry, it is a one-sixth subdivision of dental arches. The anterior sextants are composed of the incisor teeth and canines; the posterior sextants are composed of the premolar and molar teeth.


n: the color selected for a coronal or gingival portion of a dental prosthesis (crown, bridge, or implant restoration).

shearing stress

n: the stress induced in a material as a result of sliding forces over 2 areas.

shelf, buccal

n: the bony area of the mandible extended from the alveolar ridge distal to the mental foramen to the external oblique ridge. This area is covered by cortical bone and provides attachment to the buccinator muscles. It has considerable resistance to resorptive changes and is considered a primary stress-bearing area for a conventional complete mandibular denture or a mandibular partial denture with a free-end distal extension.

shim stock

n: a thin strip (8-12 μm) used to mark or confirm the point(s) of contact on natural teeth, artificial teeth, or a restoration. It is used to facilitate occlusal and proximal contact adjustment.


n: a term used to refer to salivary gland inflammation.


n: any substance or agent that stimulates salivary secretion.


n: salivary flow more than the normal rate.


n: a cavity or hollow space in the body.

sinus tract

n: a communication between a pathologic space and an anatomic body cavity.


n: slang for any osseointegrated dental implant fixture that is not in function.


n: the process of shedding necrotic tissue.

SNA angle

n: acronym for sella-nasion-A point; in analysis of a cephalometric radiograph, it is an angle that indicates the relationship of the maxillary basal arch to the anterior cranial base. It denotes whether the maxilla is in a normal, prognathic, or retrognathic position.

SNA angle

n: acronym for sella-nasion-B point; in analysis of a cephalometric radiograph, it indicates the relationship of the anterior limit of the mandibular basal arch to the anterior cranial base. It denotes whether the mandible is in a normal, prognathic, or retrognathic position.

socket preservation

n: - any graft material that maintains the alveolar bone dimensions post tooth extraction.

soft splint

n: (1) a dental device (appliance), fabricated from a resilient material, such as flexible acrylic or vinyl, which covers the upper, lower, or both arches to protect them from trauma or disclusion. An athletic mouthguard is an example. Unlike its hard counterpart, this appliance is used only for shortterm indications because of its lack of durability. (2) A characteristic of a portion of an occlusal splint; generally, resilient acrylic placed on the intaglio surface for comfort or increased retention.

soldering index

n: (1) using a heat-stable investment material to form a refractory cast in order to capture the exact orientation of the units to be soldered that were retrieved via a pickup impression; (2) fixing the relative positions of units to be soldered through a rigid connecting material. Fixation of this type is often used in conjunction with an implant analog master cast to accurately capture implant prosthetic unit positions on their respective fixtures.


n: the art and science of artificial replacement of missing or deformed parts of the body with medical-grade silicone, glass, and/or acrylic. Often these prostheses are anchored to the body through the use of osseointegrated implants with clips, snaps, or magnets.


(sonicated, sonicating, sonication) v: application of sound energy to agitate particles in a solution. Often used to create air bubbles through cavitation in order to disrupt microorganisms.


n: serial measurement of the thickness of intraoral soft tissue in order to map the topography of the underlying bone.

speaking space

n: the dynamic air space between intraoral structures (eg, the incisal or occlusal surfaces of the opposing teeth) during speech.


n: a representative sample removed from the whole for analysis in order to make a diagnostic or histologic characterization.


n: a slight, pointed, needlelike bone piece. In dentistry, a small bony fragment that is either loose or attached to the maxilla or mandible soft or hard tissues following a tooth extraction.


n: a rigid or flexible appliance that retains or protects a displaced, fractured, or movable part in a specific position.


v: (1) regarding dentistry, the connection of 2 or more teeth into a nonmobile unit by means of fixed or removable restorations or appliances; (2) regarding physiology, protracted muscle spasms that impede or prevent movement.

split-cast method

n: (1) technique for mounting indexed casts on an articulator to facilitate their removal and replacement on the instrument in the same relationship; (2) method of checking an articulator’s ability to accept or be adjusted to a maxillomandibular occlusal record.

split-cast mounting

n: a technique of mounting casts where the base of the dental cast is grooved and indexed to the mounting ring’s base. The procedure allows for verification of the mounting accuracy, ease of removal, and precise replacement of the casts.

split-thickness graft

n: a transfer of a partial thickness (depth-wise) skin or mucous membrane tissue composed of epithelium and a portion of the dermis to a desired site different than the site of origin.

spontaneous fracture

n: breakage of bone occurring without any apparent external damage or trauma. Also known as a pathologic fracture. The fracture may be caused by osteoporosis, osteosarcoma, or other necrotic condition.

spoon denture

n: an obsolete term for a claspless maxillary interim removable dental prosthesis that has a spoon-shaped palatal resin base. The resin base is limited to the central portion of the palate and therefore does not contact the lingual surfaces of the maxillary teeth. Frequently, it is used during periodontal treatment because the design of the resin base does not contact the teeth, so it permits surgical procedures and does not promote plaque collection around the teeth.

Staphylococcus aureus

n: aerobic bacteria characterized as being gram-positive and nonmotile that presents as cocci, chains, clusters, or pairs; frequently found in the nares, gingiva, and sputum; appears as a white, pink, or red pleb on the skin.

Staphylococcus epidermidis

n: aerobic bacteria characterized as being gram-positive, nonmotile, and spherical in nature; frequently found in the supragingival plaque; they can cause infection in compromised hosts.

stay plate

n: a temporary partial denture that is used while a patient’s gums and supporting bone are healing after tooth removal. It replaces the missing tooth or teeth and can help the patient with chewing and speaking until a more permanent solution is achieved. A stay plate also helps maintain the patient’s appearance and keeps the remaining teeth in the same arch from shifting.

steam cleaning

n: using pressurized steam, debris is removed from objects; in dentistry, this process is used to remove debris from a restoration, framework, or dental prosthesis.


(pl, stenoses) n: a narrowing in the diameter of a passage; may occur by constriction, occlusion, or inflammation adj, stenotic.


n: prosthesis used to hold grafts together or to maintain patency of orifices, vessels, or ducts; in dentistry; a prosthetic device used to prevent movement of hard and soft tissues to promote healing and protect from infection.


adj: complete absence of all microbial life, including transmissible agents (eg, fungi, bacteria, viruses, spore forms) on a surface; contained in a fluid, in medication, or in a compound, such as biological culture media.

sterile technique

n: the process of establishing an aseptic environment during a surgical operation by using various sterilization and asepsis methods for all materials, instruments, and surfaces involved in the surgical procedure, including the surgical site.


n: all forms of viable microbial life are nonexistent.


n: a term referring to any process that eliminates or kills all forms of microbial life.

Stillman’s cleft

n: a localized V-shaped, apostrophe- shaped, or a slitlike indentation or recession at the midline of the gingival margin of a tooth. It may extend several millimeters toward the mucogingival junction or even to or through the junction.


v: the process of producing a stippled appearance of the attached gingiva or its artificial replacement.


n: the pitted orange-peel appearance of the attached gingiva, which is considered a structural characteristic of a healthy gingiva.

stock tray

n: a metal or plastic prefabricated impression tray used principally for preliminary impressions; available in several standardized sizes and shapes.


(pl, stomata or stomas) n: any surgically constructed opening made for drainage or other purposes.


n: inflammation of the mucosal tissues of the oral cavity.

stress-bearing region

n: area of the maxillary or mandibular jaws that are capable of supporting a denture prosthesis. This represents the residual ridge, buccal shelf area, and retromolar pad for the mandibular arch and the residual ridge and the palate for the maxillary arch.

stress concentration

n: a location in a subject or a system where there is a remarkably higher stress compared with other areas or points in response to a particular load.

stress director

n: any device, appliance, or system that redirects the occlusal forces of the stomatognathic.


n: the connective tissue that forms the framework of an organ, gland, or structure.

stylus tracing

n: a planar tracing showing the marginal movement of the mandible as it is scribed on a plate attached to an arch by means of a stylus device attached to the opposing arch. The produced shape depends on the location of the marking point relative to the tracing table during marginal mandibular movement.

subantral augmentation

n: modification of a maxillary sinus involving the lifting (elevation) of the sinus membrane and placement of a hard tissue graft in order to provide or build a host site for dental implants. Also known as sinus lift, sinus graft.


adj: a disease falling before or between the acute and chronic stages.

subcondylar fracture

n: a fracture located below the condylar head and within the limits of the condylar neck.

subgingival margin

n: the restoration or tooth preparation finish line that is positioned apical to the free gingival margin.


adj: below or beneath the tongue.

sublingual fossa

n: a shallow concavity on the lingual surface of the mandible above the mylohyoid line that accommodates the sublingual gland.


n: in reference to the temporomandibular joint, an incomplete dislocation or misalignment of the condyle in its fossa.

subocclusal connector

n: a nonrigid interproximal connector placed apical to and not in alignment with the occlusal plane.

subocclusal surface

n: an obsolete term for a segment of a tooth’s occlusal surface that is beneath the level of the occluding portion of the tooth.

subperiosteal dental implant

n: a type of dental implant placed beneath the periosteum that rests on the surface of the bone with abutments that protrude through the oral mucosa and are used to support a dental prosthesis. See also implant, oral.

subperiosteal dental implant abutment

n: an obsolete term for the component of a subperiosteal implant that protrudes through the oral mucosa and is used for retention of a dental prosthesis. See also abutment.

subperiosteal dental implant substructure

n: the component of a subperiosteal implant located beneath the periosteum that provides support for a dental prosthesis via abutments that protrude through the oral mucosa. Also known as the implant body.

subperiosteal dental implant superstructure

n: dental prosthesis metal framework that is supragingival in location and provides support for artificial teeth and/or denture base material that fits onto the subperiosteal implant abutments.

subtraction radiography

n: manipulation of a radiograph photographically or digitally where background images are eliminated to highlight areas for comparison.


adj: more than the routine or normal number.


n: the upper (most superior) part of a fixed or removable dental prosthesis of which the replacement teeth and associated gingival/alveolar structures are parts


n: the formation or discharge of pus.


n: eruption of a tooth or teeth above the standard occlusal plane.


adj: (1) located above the gingival tissue; (2) portion of a tooth structure that is coronal to the gingival crest.

surgical curettage

n: see under curettage

surgical occlusion rim

n: an occlusion rim used for recording the maxillomandibular relationship and for guidance in positioning replacement or denture teeth.

surgical prosthesis

n: any ancillary prosthesis intended for a short-term application that can be inserted at the time of surgery.

surgical splint

n: an ancillary appliance used to maintain tissues in a new position after surgery. It is commonly used to reset normal occlusal relations during a period of immobilization. The appliance is frequently designed to make use of existing teeth and/ or alveolar processes as points of anchorage to help stabilize and immobilize broken bones during the healing phase. Often a patient’s existing prosthesis can be used with modification to serve this purpose.

surgical stent

n: a device used to facilitate and guide surgical procedures.

surgical template

n: (1) a guide conforming to the tissue surface and used for surgically shaping the alveolar process; (2) a guide for the surgical placement of implants in the correct position and angulation in the alveolar bone; (3) a guide for establishing proper occlusion during orthognathic surgery.


v: to connect tissues that have been separated by a traumatic injury or an intentional surgical wound. The cut ends of the tissue are approximated and kept together with an appropriate thread-like material called a suture.


(pl, symphyses) n: (1) a type of cartilaginous joint that connects opposing bony surfaces with a plate of fibrocartilage; (2) the immovable dense bony connection between the right and left halves of the adult mandible at the midline.


n: any characteristic of a disease or medical condition that is subjectively perceived.

synovial fluid

n: a viscid fluid secreted by the synovial membrane found inside joint cavities.

synovial membrane

n: the articular membrane consisting of specialized endothelial cells that have the ability to produce a fluid that fills the joint cavity.


Table, occlusal

n: the occlusal surface of posterior teeth (premolars and molars).


n: in dentistry, the amount of convergence of opposing external surfaces of a tooth or tooth preparation. The extension of lines representing the external walls form the angle of convergence


n: permanent dilation of blood vessels near the surface of the skin or mucous membranes that results in small focal red lesions that are commonly seen on the nose, cheeks, and chin. Also called angioectasias or spider veins.

telescopic crown

n: a secondary crown that fits over a fixed or nonremovable prosthesis, such as a primary crown, coping, bar, or any other suitable rigid support for the dental prosthesis.


n: a guide or pattern that helps determine the shape of an object being fabricated or aids tooth arrangement.

temporary prosthesis

n: see under prosthesis.

temporomandibular disorder

n: any abnormality of the temporomandibular joint and/or muscles of mastication or associated tissues leading to pathologic symptoms or impaired function of the temporomandibular joint. Disorders may be acquired, such as myofacial pain, disc displacement with or without reduction, degenerative joint disease, or disorders acquired from trauma or neoplasms; they may be developmental, such as those of systemic or genetic origin; or they may be caused by abnormal facial growth.

temporomandibular joint

n: connection between the condylar head of the mandible and the articular fossa of the cranial temporal bone. The joint consists of 2 compartments (upper and lower) separated by a disc. Movement in the upper joint partition is generally translational, while that in the lower joint partition is typically rotational. The joint is classified as ginglymoarthrodial, as it is both a hinge and sliding joint. Also known as the mandibular joint.

temporomandibular joint hypermobility

n: pathologically excessive mobility of the temporomandibular joint commonly associated with internal disc derangement.

tensile stress

n: the resistance of a material to longitudinal force, measured by the smallest amount of longitudinal force required to break up the material; axial stress that causes elongation of a material along the direction of the applied force.


n: the condition of being stretched or strained.


n: the production of birth defects in a fetus or embryo.

terminal jaw relation record

n: a record of the mandible in relation to the maxilla in the terminal hinge position.

therapeutic prosthesis

n: an appliance that assists in the treatment of periodontal disease.

thermal expansion

n: heat-induced expansion of a material or substance.


adj: the ability of a material to soften with heat application and harden with cooling.


n: a raised helical ridge found on screws, nuts, and bolts.

thread crest

n: the superior or outer portion of a screw thread.

thread flank

n: the portion of a screw thread that joins the thread root to the screw crest.

thread root

n: the apical portion of a thread that comes in contact with the screw shaft.

thread run out

n: the end section of a threaded shank that is not cut or rolled to full depth providing the transition between the fastener shank and full depth threads.


n: a disorder of blood characterized by overproduction of platelets.


n: a disorder of blood characterized by a reduction of platelets.

tinted denture base

n: coloration of a denture base to resemble the natural appearance of oral mucosal tissues.


n: specialized cells organized into a unit so that desired or intended functions can be accomplished.

tissue displaceability

n: the quality of tissue that allows it to be displaced to a position not achieved by the natural and relaxed state, different tissues allow for varying degrees of displacement.

tissue displacement

n: alteration in form or position of tissues that can occur when pressure is applied; this may alter the accuracy of oral tissue impressions during impression taking.

tissue integration

n: the ability of tissue to attach to nonliving materials as with the osseous integration of dental implants, eg, a dental implant

tissue registration

n: an obsolete term for the process of recording the shape of tissues with a material suitable such that distortion does not occur.


n: an element that has qualities making it biocompatible, bioinert, and nontoxic.

titanium alloy

n: a mixture of titanium with other elements so as to achieve advantageous qualities. Dental implants are frequently made of titanium with the addition of 6% aluminum and 4% vanadium to increase the tensile strength and resistance to fatigue. These alloys form a titanium oxide (TiO2) surface layer that interfaces with the bone.

titanium oxide

n: a substance that forms on the surface of titanium and is 10 to 100 angstroms thick, forms almost instantly, and has properties that allow for resistance to corrosion, thereby reducing the opportunity of chemical breakdown in biological fluids.


n: a radiograph that demonstrates images at various depths based on a method of moving the film during exposure.


n: an apparatus that is used to create a tomogram. The machine allows for the movement of the film in one direction, while the source of radiation moves in an opposite direction to produce images at a targeted depth within the tissues.


n: a method of acquiring images of a selected plane within a body produced by moving the radiation source and the film in directions so as to rotate around the targeted axis blurring all but the chosen area of study. Also known as body section radiography.

tongue thrusting

n: the infantlike tendency to push the tongue between the incisors or anterior alveolar ridges during swallowing, which can lead to malocclusion, such as anterior open bite, altered/abnormal jaw growth, or abnormal jaw functions.

tonus, muscle

n: (1) regarding the skeletal system, it is the minimal muscle contractions that maintain posture; (2) regarding the vascular system, it helps blood return to the heart.

tooth arrangement

n: the art of placing teeth into determined ideal positions on a denture base so as to achieve the desired results related to esthetic and functional objectives. Trial placements are frequently done allowing for further movement to enhance the initial results.

toothbrush trauma

n: toothbrush-induced damage to teeth or gingiva.

tooth color selection

n: to choose an appropriate shade of a tooth or teeth so as to harmoniously match the appropriate needs of a patient.

tooth extrusion

n: the tendency of a tooth to continue the state of eruption. It can be excessive when the forces that naturally limit eruption are not present. Also known as overeruption.

tooth form

n: the totality of various physical contours that allow for differentiation of teeth to establish their esthetic and functional value.

tooth preparation

n: shaping a tooth to accept a restoration; this may involve the removal of decayed and/or healthy enamel, dentin, and/or cementum.

tooth selection

n: choosing the size, color, and shape of a tooth or teeth for a prosthesis.

tooth-size discrepancy

n: teeth that are not within normal size parameters compared with the rest of the arch or opposing arch.

tooth supported

adj: a prosthetic device that is completely supported by adjacent teeth.

tooth-supported base

n: the base of a prosthetic device that is completely supported by adjacent teeth.

tooth-supported denture

See overdenture.


n: surface application.


n: surface characteristic.


n: measurement or application of a force to rotate an object around an axis.


(pl, tori) n: rounded protruding bony projection found at the maxillary midline of the hard palate or on the mandible’s lingual surface in the premolar/ molar region. It is often bilateral.


n: the ability of a material to resist fracture when stressed.


n: the degree to which a substance can damage an organism. The reaction can be localized or systemic and the response level depends on the toxin’s dose, rate of release, route of administration, duration of exposure, and specific characteristics.


n: a poisonous substance produced by an organism or within living cells.


n: interconnected bony spicules in cancellous bone

transcranial oblique radiograph

n: a radiographic view of the temporomandibular joint taken by projection from a superior position on the opposing side of the skull.

transcutaneous electrical neural stimulation

n: application of intermittent electrical stimulation through the skin to nearby nerves for the purpose of relieving pain.


adj: something that passes through epithelium.

transepithelial abutment

n: a slang term for a dental implant abutment that attaches to a dental implant and passes through the epithelium into the oral cavity.

transfer coping

n: a thin cap used to accurately transfer the position of a die or analog into an impression.


n: examination of a body structure by passing an intense light through it.

transit dose

n: measurement of the amount of primary radiation that has transmitted through (beyond) the patient and is in line with the transmission axis of the central ray.

transitional contour

n: the shape that exists at the point where a dental implant abutment and the corresponding dental implant body meet or join.

transitional denture

n: a denture to which artificial teeth are added when a natural tooth (teeth) are removed or lost. This transitional denture is intended to serve as an interim prosthesis and may be replaced once the soft tissue has healed after tooth (teeth) extraction.


n: the quality of a substance that permits light to partially pass through it. In dentistry, it refers to giving the appearance of partial transparency that allows for the natural shading of an artificial tooth (teeth).


n: portion of a dental implant that traverses through the mucosa and attached or unattached gingiva.


adj: transition of an object through the internal and external cortical plates of bone into and beyond the oral cavity mucosa.

transosteal dental implant

n: (1) a dental implant that transverses inferior and superior cortical plates of bone and passes through the full thicknesses of the alveolar bone and oral cavity mucosa. (2) A dental implant that achieves its foundational support from the inferior border of the mandible. Additional support pins may penetrate the alveolar bone through the inferior cortical plate of the bone or may penetrate inferior and superior cortical plates of the bone. The support pins may exit into and beyond the oral mucosa. This implant supports a dental prosthesis and is usually limited to the symphysis of the mandible. Also known as a staple bone implant.


n: (1) regarding tissue transplantation, it is the removal of tissue from one person’s body and placing it in another person’s body or the removal of tissue from a donor site in one’s own body and placing it in another location in one’s body. The intent is to replace the recipient’s damaged, diseased, or missing organ. (2) Regarding bone transplantation, it is transporting bone tissue from one location of the body to another part of the body, usually to increase the volume of bone for latter implant placement; autogenous, or allographic.


n: exudate fluid that passes through a tissue surface or membrane; usually associated with inflammation.

transverse horizontal axis

n: an imagined line about which the mandible rotates within the sagittal plane.


n: eruption of a tooth into a position naturally occupied by another; transposition of a tooth.


n: the physical condition consequential to an injury or wound.


adj: having the ability to produce injury.

traumatogenic occlusion

n: an obsolete term for a malocclusion that can injure the occlusal tooth surface or supporting bone and/or soft tissue structures.

treatment denture

n: a temporary dental prosthesis used to support and retain tissue during the healing phase in preparation for construction of the definitive prosthesis. See also interim prosthesis.

treatment plan

n: the recommendations for a patient to follow to improve oral health after a comprehensive examination and diagnosis.


n: hollow rotary circular instrument that removes a disk or cylinder of bone or tissue; it can be used to create a trough around an endodontic post to assist in its removal from a natural tooth or to remove a dental implant from bone.

trial base

n: a device or material that represents the base of a removable dental prosthesis and usually has an attached wax rim. The device is, used to record the maxillomandibular relationship for the purpose of setting denture teeth in their proper functional and esthetic location.

trial denture

n: placement of teeth, usually in wax, to evaluate the proposed maxillomandibular relationships, esthetics, and function of the prosthesis.

trial flask closure

n: preliminary closure of a dental prosthesis processing flask that ensures that the mold is completely filled with finishing material and allows excess material to be eliminated.

trial placement

n: a setup of denture teeth (usually in wax) on a base material so that a try-in denture may be placed in the patient’s mouth to verify esthetics and necessary records or to verify any other necessary steps before completion of the denture.

tricalcium phosphate

n: an inorganic porous particulate biodegradable ceramic material made up of a calcium-phosphate mixture and used as a scaffold for bone regeneration.


n: tooth root that is divided into 3 distinct individual roots.


adj: concerning the fifth cranial nerve (trigeminal nerve).


n: a small, rounded, bony nodule, eminence, or projection.


n: a projection or protuberance on a bone that often serves for the attachment of muscles.

tunnel dissection

n: a surgical procedure in which the periosteum is dissected from bone through a small opening made by an incision; access to the desired bone site is through a tunnel-like opening under the soft tissue.

tunnel preparation

n: a surgical procedure implemented on a multirooted tooth (usually mandibular molar) that results in a totally opened furcation. The procedure is performed to allow easier and complete access to the area between the roots for the purpose of oral hygiene and improved tissue health.


adj: swollen and distended or in a state of congestion.


n: a model used in training dental students that represents the oral cavity. The model includes a replica of the natural dentition and alveolar mucosa and is set to average condylar movements. Also known as a typodent.


UCLA abutment substand

n: an informal term used to describe a screw-retained dental crown that is screwed directly into the implant body without an intervening abutment


(ulceration) n: a lesion on the surface of skin or mucosa that is usually associated with inflammation that results in the loss of soft tissue integrity in the area. It is characterized by absence of the epithelium.

ultimate strength

n: the maximum stress a material can withstand at its point of rupture. Also known as ultimate tensile strength


n: the detailed structure of a biological specimen that is beyond the resolution power of the light microscope; eg, it may be observable using electron microscopes or technologies that provide greater resolution.


adj: a wavelength of electromagnet radiation that is shorter than the violet end of the visible spectrum but longer than that of X-rays. Normally it refers to wavelengths <380 nm.


v: to create irregular areas that provide mechanical retention for dental material placement.


adj: a surface that may be irregular, wavy, surged, swollen, heaved, rippled, billowed, flowing, or rolled. Can be used to describe a colony of microorganisms.

uniform color space

n: if a color space is perceptually uniform, it means a change of length x in any direction of the color space would be perceived by a human as the same or an equal change.


adj: confined or relating to only 1 side.

unilateral subperiosteal implant

n: an eposteal dental implant that provides for 1 or more abutments and that supports and/or retains a removable or fixed dental prosthesis on 1 side of a partially edentulous dental arch.


adj: the vertical or normal position of a tooth.


n: a vascular reaction of the skin that presents with pale red, raised, and itchy bumps. Commonly referred to as hives and may be associated with the sensation of burning or stinging. It often occurs in response to an allergic reaction; however, it can be induced by nonallergic conditions. Allergic-induced reactions usually last less than 6 weeks and are called acute urticaria. Nonallergic reactions usually last longer than 6 weeks and are called chronic urticaria.



n: the development of blood vessels in a tissue by natural or surgical means.

vascular pain

n: a type of deep pain that develops when blood flow is interrupted to a tissue, organ, or nerves.


n: a mechanism that results in a decrease in vessel lumen diameter, especially in arterioles, which in turn increases pressure within the vessel or creates a state of hemostasis.


n: any agent that promotes vasoconstriction. Used in dentistry to extend the duration of local anesthesia and/or to reduce bleeding during surgical procedures.


n: any agent that reduces blood pressure by reducing peripheral vascular resistance.


n: the process of increasing the lumen diameter of a blood vessel, especially an arteriole.


n: a membranous structure that partly obscures an opening or covers another structure.


n: a thin sheet of material used in the outermost aspect of a body (tooth, denture) as a protective or ornamental finish.

vertical dimension

n: measured by determining the distance between 2 arbitrarily selected points on the face that are easily located and reproduced as needed. On the facial midline, one reference point is above the mouth and the other point is below the mouth.

  • occlusal vertical dimension: the vertical dimension of 2 designated points on the face when the teeth are in contact in centric occlusion.
  • rest vertical dimension: the vertical dimension of 2 designated points on the face when the mandible is in its postural position.

vertical dimension decrease

n: an obsolete term for a change in the teeth, denture base, soft tissue, or bony tissue that brings the maxillary and mandibular dental arches closer together while in occlusion.

vertical dimension increase

n: an obsolete term for a change in the teeth, denture base, soft tissue, or bony tissue that increases the distance between the maxillary and mandibular dental arches while in occlusion.

vertical dimension of speech

n: an alternative to the conventional vertical dimension technique. This distance is frequently measured while the patient is emitting an “s” sound.

vertical opening

n: see vertical dimension.


n: a record of the vertical dimension of occlusion with the jaws in centric relation. It is used in complete removable dental prosthesis fabrication.


n: an elevation of the skin or mucous membrane <5 mm in diameter that contains watery fluid. See also bulla.


n: plastic surgery of the vestibular region of the mouth designed to restore alveolar ridge height (deepen the vestibular trough) by lowering the muscles that attach to the buccal, labial, and lingual aspects of the jaws.

vibrating line

n: an imagined line across the posterior part of the maxillary palate marking the division between the mobile and nonmobile tissues of the palate that can be visualized when the mobile tissues are in function.

Vincent’s angina

n: painful membranous ulceration of the oropharynx, throat, or gums that may be caused by Fusobacterium nucleatum infection. It is usually associated with necrotizing ulcerative periodontitis and referred to as trench mouth.

visceral pain

n: deep somatic pain that results from the activation of nociceptors of the mucosal linings, walls of hollow viscera, parenchyma of organs, glands, dental pulps, and vascular structures. These visceral structures may not respond to stimuli that normally evoke pain, such as cutting or burning; however, they are sensitive to distention (stretch), ischemia, and inflammation.

visible spectrum

n: the portion of the electromagnetic radiation spectrum detectable by the human eye. It is referred to as light or visible light and involves wavelength from approximately 390 to 700 nm.


n: an instrument used in determining pulp vitality that measures a tooth’s response to variable intensities of electrical stimulus.


Wandering abscess

n: a localized abscess formed by pus burrowing along fascial planes and forming fingerlike projections that may discharge exudate at a distance from the primary focus of infection. Also known as a migrating abscess.


v: the process of contouring wax into a needed shape, such as making a wax base for a trial-fit denture.

wax pattern

n: a wax form that represents an item to be made

wedge procedure

n: a surgical technique designed to remove unwanted or excessive soft tissue from an edentulous area (ie, maxillary tuberosity).


n: washed and ground pure white chalk (calcium carbonate) used for polishing dental materials

wire splint

n: a dental appliance used to stabilize trauma- induced or periodontally involved teeth that are loose. The wire is attached to the mobile tooth (or teeth) and then also fixed to stable teeth on either or both sides of the mobile tooth (teeth). An appliance that consists of 1 component attached to each dental arch that are connected by intermaxillary wires or elastic bands and is used to reduce or stabilize maxillary or mandibular fractures.

Wolff’s Law

n: theory which states that a bone in a healthy person will develop or adjust to a shape or structure that is most suited to resist the loads (forces) being applied to it.


n: force moved over a distance.

work authorization

n: a signed prescription that the dentist provides to the dental laboratory specifying the type of dental appliance or prosthesis to be made and the materials to be used for its construction.

working articulation

n: the points of occlusal contact of the teeth on the side toward which the mandible is moved.

working contacts

n: an obsolete term for the points of occlusal contact the opposing teeth make on the side toward which the mandible has been moved.

working model

n: the dental cast used to construct a dental appliance or prosthesis.

working occlusal surface

n: an obsolete term for the external area of a tooth or teeth on which mastication occurs.

working occlusion

n: an obsolete term referring when the mandible is moved from its centric occlusal position; it is the occlusal contacts made on the side toward which the mandible is moved.

working side

n: when the mandible is moved from its centric occlusal relationship into a lateral excursion it is the side toward which the mandible is moved.

working side condyle

n: when the mandible is moved into a lateral excursion it is in reference to the condylar process (the rounded protuberance at the superior end of the mandible that forms the articulation with the skull) on the side toward which the mandible is moved.

working side condyle path

n: when the mandible is moved into a lateral excursion it is the path the condyle travels on the working side.

working side contacts

n: when the mandible is moved from its centric occlusal relationship into a lateral excursion it is the point(s) of contact made by the teeth on the side toward which the mandible is moved.


n: loss of integrity of a tissue due to injury, trauma, or surgery.


adj: shaped into a form by use of hands or tools.


Xenogenic graft

n: placement of a tissue obtained from an animal species over, or into, an affected area of another species. Also known as a heterologous graft.


n: the dry photoelectric process by which an X-ray image is captured using metal plates coated with a semiconductor, such as selenium.


n: dryness of the mouth due to lack of or inadequate secretions (eg, inadequate salivary secretions).



n: classified in the kingdom Fungi, these eukaryotic microorganisms are mostly unicellular but can become multicellular through the formation of pseudohyphae or strings of connected budding cells. Yeast can reproduce by mitosis, asymmetric division. or budding. Yeast can become pathogenic in the body, including the oral cavity, especially in people who are immunocompromised through disease or drug therapy.

Young’s modulus

n: describes the rigidity or stiffness of a material usually given the symbol E. It is a measure of elasticity equal to the ratio of the stress acting on a substance to the strain produced. A higher modulus (GPa, psi) signifies a greater rigidity or stiffness to the material. Also called modulus of elasticity.


Zero-degree teeth

n: posterior denture teeth having flat planes or zero-degree cusp angles relative to the horizontal occlusal surface of the tooth. See also nonanatomic teeth

zirconia ceramic post

n: a ceramic post used instead of metal posts in the restoration of endodontically treated teeth. The ceramic material is preferred to the metal posts for esthetic reasons. Ceramic posts are usually used with a composite resin or compression ceramic to form the core.