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Record - Information committed to and preserved in writing or in any medium capable of preserving the information.

Facebow R. - Registration, by means of a facebow, or axis transfer bow, relating the maxillae to the transverse mandibular axis of the mandible. (See also Facebow).

Interocclusal R. - A record of the positional relation of the teeth or jaws to each other.

Centric I.R. - A record of the centric relation jaw position.

Eccentric I.R. - A record of the jaw in any position other than centric relation.

Lateral E.I.R. - A record of the jaw in any lateral position.

Protrusive E.I.R. - A record of the jaw in any protruded position.

Recorder, mandibular movement - (See pantograph; tracing, needlepoint).

Recording - (See pantograph; tracing, needlepoint).

Reference plates - (See plates, reference).

Reflex - A reflected action or movement, the sum total of any specific involuntary action.

Jaw R. - An extension, flexion that is initiated by a downward tapping on the symphysis area of the mandible.

Stretch R. - The reflex contraction of a muscle in response to longitudinal stretching.

Registration - The record of desired jaw relations made in order to transfer casts to an articulator maintaining these same relations.

Occlusal R. (occlusal markings) - Clinical detection of the patterns and disharmonies of occlusion by the interposition of articulating paper, wax, etc., between the teeth during mandibular closure and excursive movements.

Rehabilitation - Restoration of form and function; to restore to a former capacity or position; to re-establish. (See also resolution).

Mouth R. - (See rehabilitation, oral).

Occlusal R. - Restoration of the form and function of the occlusal surfaces of the teeth.

Oral R. (Oral reconstruction) - To restore form and function to the gnathic system by rebuilding the parts in need of repair.

Relation - The designation of the position of one object as oriented to another.

Acentric R. - (See relation, jaw, eccentric).

Centric Relation - The physiologic relationship of the mandible to the maxillae and the cranial base when both condyles are properly related to their articular discs. The condyle-disc assemblies are stabilized against the posterior slopes of the articular eminences of the glenoid fossae. At this point the condyles are in a braced position that can be recorded. This relation may occur at varying vertical dimensions of rotation of the mandible preceding any translation of the condyles.


     1. Centric relation is considered a border position that may be related to the mandibular transverse axis.

     2. Centric relation is therefore an anatomically and physiologically stable, repeatable posture of the mandible and can be considered a most acceptable treatment and reference position.

     3. Centric relation is a position that is not commonly coincident with the maximum intercuspation of the dentition.

     4. Centric relation when coincident with the maximum intercuspations of the teeth can be considered in the mandibular posture known as centric relation occlusion.

Cusp-embrasure R. - The relation of a stamp cusp to the appropriate occlusal embrasure in the opposing arch. (Tooth-to-two teeth).

Cusp-fossa R. - The relation of a stamp cusp to the appropriate fossa in the opposing tooth. (Tooth-to-tooth).

Eccentric R. - (See relation, jaw, eccentric).

Jaw R. - Any relation of the mandible to the maxilla.

Acquired J.R. (convenience jaw relation) - An eccentric relation that is assumed by habit in order to bring the teeth into a convenience occlusion; habitual occlusion.

Centric J.R. - (See relation, centric).

Eccentric J.R. - Any jaw relation other than centric relation.

Relationship - The condition of being associated or interconnected.

Occlusal R. - The individual and collective relationship of the mandibular teeth to the maxillary teeth and the relationship of the adjacent teeth in the same dental arch.

Abnormal occlusal R. - Occlusal relationships that deviate from the regular and established type in such a manner as to produce esthetic disharmonies, interference with mastication, occlusal traumatism and/or speech difficulties.

Repositioning splint - (See appliance, occlusal orthopedic).

Resolution - The re-establishment or rehabilitation of a system to a state of health and function. (See also rehabilitation).

Rest position - (See position, rest).

Retainer - An orthodontic appliance used to hold and allow stabilization of the position of the teeth following orthodontic treatment in an attempt to prevent relapse of the corrected result. (See also appliance, orthodontic).

Retrognathic - Having a recessive lower face.

Retrusion - (See movement, dynamics of mandibular).

Ridge - A linear elevation of the surfaces of teeth.

Central R. - The greatest convexity on the facial or lingual surfaces of cusp units from their cervical line to the incisal or occlusal surface.

Marginal R. - (Peripheral Marginal R., Occlusal Marginal R.). The ridges bordering the occlusal table of the tooth; the highest perimeter of the occlusal surface of a tooth.

Distal M.R. - The marginal ridge that extends distally from each cusp tip.

Mesial M.R. - The marginal ridge that extends mesially from each cusp tip.

Transverse M.R. - The parts of the marginal ridges which extend from the facial segments across (trans) to the lingual segments of posterior teeth. Each posterior tooth would have a mesial transverse marginal ridge and a distal transverse marginal ridge.

Oblique R. - A variable ridge crossing obliquely the occlusal surfaces of maxillary molars. It extends from the distal aspect of the mesio lingual cusp in a distofacial direction and coalesces with the triangular ridge of the distofacial cusp at the central developmental groove.

Triangular R. (major primordial) - A triangular shaped ridge running from the cusp tip to the central developmental groove.

Rotating condyle - (See condyle, working).

Rotating path - (See path, working).

Rotation - To revolve or turn round a center or axis.


Selective cutting, grinding - (See equilibration, occlusal).

Sella turcica (S) - Cephalometric landmark; the center of the pituitary fossa of the sphenoid bone.

Shearing cusp - (See cusp, shearing).

Side - A place, space or direction with respect to a center of a line of division.

Chewing S. - (See side, working).

Non-working S. - The side of the mouth opposite the working side; the side that is not working when the other side is working. The non-working movement that results would be inward, downward and forward for the non-working condyle. (See also condyle, non-working).

Working S. - The side to which the mandible is moved; the side of the mouth on which the food bolus is formed to facilitate chewing; the chewing side. (See also condyle, working).

Side shift (transtrusion) - The bodily side thrust of the mandible, across thrust. (See also movement, dynamics of mandibular).

Immediate S.S. - A term affixed to the immediate side thrust capabilities of the condyles that precede their rotational movement.

Progressive S.S. - The side thrusting capabilities of the condyles that occur with the rotational movements. A fixed ratio of transtrusion with rotation. The gradual side shift.

Space - A delimited, three-dimensional region.

Freeway S. - The interocclusal distance or separation between the occlusal surfaces of the teeth when the mandible is in its physiologic rest position. (See also distance, interocclusal).

Spasm - A sudden involuntary contraction of a muscle or muscle group.

Muscle S. - Increased muscular tension and shortness of a muscle that cannot be released voluntarily and that prevents lengthening or relaxation of the muscles involved.

Spee, curve of - (See Curve of Spee).

Spiral, dynamic - The three-dimensional imaginary spiral that can be observed by visualizing planes of space that intersect the cusp tips of all teeth. The cant or attitude of the teeth in the bony arches are such that tooth positions are a resultant composite subservient to a two control system, e.g., the lingual cusps of the maxillary molar teeth are longer than their facial cusps, but the evolution of the spiral is apparent form posterior teeth to anterior teeth, as the second premolar cusps are the same height and the first premolar lingual cusp is shorter than its facial cusp.

Splint - A somewhat rigid appliance for the fixation of displaced or moveable parts, e.g., surgical splint. (See also Stent).

Occlusal S. - (See appliance, occlusal; occlusal orthopedic).

Stamp cusp - (See cusp, stamp).

Stent - Immobilization by pressure (e.g. surgical, radiation or hemorrhagic). (See also Splint).

Stomotognathic system - (See system, stomatonathic).

Study model - (See cast).

Stylus - A sharp-pointed writing instrument. It is commonly used in dentistry as the writing device on markable plates to capture the three-dimensional effects of mandibular movement, e.g., mandibular movement recorder, pantographic tracings.

Subluxation - Term used to characterize the downward, eccentric position of the condyle as it relates to its fossa and articular eminence; inferior displacement of the condyle(s).

Subspinale - (See Point A).

Supplemental grooves - (See groove, supplemental).

Supramentale - (See Point B).

Surface - The outer portion of a mass or object.

Buccal S. - (See Surface, facial).

Facial S. - The side of a tooth or any structure adjacent to and facing either the lips or cheek. This term includes both labial and buccal surfaces.

Labial S. - (See Surface, facial).

Lingual S. - The side of a tooth or any structure adjacent to and facing the tongue.

Occlusal S. - The working surface of the coronal portion of posterior teeth; the occluding surface.

Proximal S. - The surface of a tooth or portion of a tooth that is nearest to the adjacent tooth in the same arch.

Surgery, orthognathic - Surgical procedures and techniques utilized in repositioning all or parts of the maxillae or mandible to obtain better functional relationships of their parts. Also used in cosmetic corrections of malrelated jaws. The different procedures may be classified or named as to the part being altered in the surgical technique, e.g., mandibular advancement, premaxilla shift, etc.

Surtrusion - (See movement, dynamics of mandibular).

Syndrome - A group of signs and symptoms that occur together and characterize a disease or condition.

Costen-s S. - Various symptoms of discomfort, pain or jaw pathosis claimed by Costen to be caused by lack of posterior occlusion, loss of vertical dimension, malocclusion, trismus or muscle tremor. He also claimed that auditory symptoms developed from impingement on the auriculotemporal nerve.

Myofascial Pain Dysfunction S. - Term used to define the painful episodes of the musculature of the gnathic system associated with mandibular dysfunction.

TMJ Pain Dysfunction S. - (TM disorders, TMJ dysfunction, cranio-mandibular dysfunction). An all-encompassing term used to define the painful episodes from all or any structures associated with mandibular dysfunction. It is thought to be caused by a postural occlusal imbalance associated with muscular tension induced by psychological stress. This combination may result in bruxism, clenching or grinding which is thought to trigger or precipitate the pain in the structures of the stomatognathic complex.

System - A set of organs or parts that unite in common function.

Masticatory S. - The organs and structures primarily functioning in mastication; the jaws, the teeth and their supporting structures, the temporomandibular articulation, the mandibular musculature, the tongue, the lips, the cheeks and the oral mucosa.

Stomatognathic S. - The combination of all the structures involved in the functional capabilities of the mouth.


Table, occlusal - That portion of the occlusal surface of a posterior tooth that lies within the perimeter of the cusp tips and the marginal ridges.

Table, stop, guide - That part of an articulator, usually on the anterior portion of the mandibular member, when contacted by the stop pin, that stops the closure of the articulator. It is usually the anterior point of the articulator tripod, the other two points being the right and left condyles in the articulator fossae.

Custom guide T. - (See table, guide).

Guide T. - A stop table which provides an initial centered stop for the articulator stop pin. It can be mechanically adjusted (mechanical g.t.) or custom fabricated (custom g.t.) providing a bearing surface that reflects the condylar pathways and disclusive angles in eccentric excursions.

Mechanical guide T. - (See table, guide).

Teeth - (See tooth).

Temporomandibular articulation - (See articulation, temporomandibular).

Temporomandibular joint - (See joint, temporomandibular).

Terminal hinge axis - (See axis, hinge, terminal).

Therapy - The treatment of disease or conditions.

Myofunctional T. - Use of muscle exercises to retrain or reprogram the muscles of the stomatognathic system in an attempt to help correct malocclusion and malpositioned teeth.

Tic - An involuntary spasmodic twitching or movement of muscles.

T. Douloureux - Spontaneous trigeminal neuralgia associated with a -trigger zone- and causing spasmodic contraction of the facial muscles and excruciating pain.

Tomogram - A radiographic procedure whereby shadows of various internal layers of the head and body are separated for the purpose of obtaining a radiograph showing distinct shadows of a certain layer and at the same time blurring out everything above and below the layer.

Tooth - One of the hard bodies or processes usually protruding from and attached to the alveolar process of the maxilla and mandible. Designed for the mastication of food.

Teeth - Plural of tooth.

Anterior T. - One of the incisor or canine teeth.

Posterior T. - The premolars and molars of the permanent dentition.

Tracing - A line or lines or a pattern scribed by a pointed instrument or stylus on a tracing plate or tracing paper.

Arrow point T. - The character of a needle point tracing when the stylus is attached to the mandible. (See also tracing, needle point).

Cephalometric T. - A line drawing of pertinent features of a cephalometric radiograph made on a piece of transparent paper placed over the radiograph.

Extraoral T. - A tracing of the mandibular movement made outside the oral cavity.

Gothic arch T. - The character of a needle point tracing when the stylus is attached to the maxillae. (See also tracing, needle point).

Intraoral T. - A tracing of mandibular movement made within the oral cavity.

Needle point T. (arrow point T., gothic arch T.) - A tracing made by a mechanical device consisting of a magnetized, weighted, spring-loaded or pressure activated stylus that is attached to one jaw and contacts a coated plate attached to the other jaw. Movement of the mandible causes a tracing to be formed on horizontal, vertical or both coated plates. When the stylus point is on the apex of the tracing, the mandible is said to be in the position of centric relation.

Pantographic T. - (See tracing, needle point).

Stylus T. - (See tracing, needle point).

Tragus - A prominence anterior to the opening of the external auditory meatus.

Translation - Movement of a body in which all parts move in the same direction at the same speed. The sliding, movement capabilities of the mandible.

Transtrusion - (See movement, dynamics of mandibular).

Transverse marginal ridge - (See ridge, marginal, transverse).

Traumatism - A state of injury to tissues caused by destructive forces.

Occlusal T. - Pathologic changes in a tooth and surrounding structures produced by abnormal occlusal forces.

Triangular ridge - (See Ridge, triangular).

Tripodism - Pertaining to three contacts and considered to be the most stable principle of mechanics. A term commonly used to denote contacts between the stamp cusps with their opposing fossa. The mandible can also be said to be tripodized with the condyles serving as two contacts and the occluded teeth collectively providing the third contact.

Trismus - Spasms of the muscles of mastication, resulting in an inability to open the mouth.


Unilateral - One sided.


Vertical - Perpendicular; up and down direction.

V. dimension - (See dimension, vertical).

V. opening - (See dimension, vertical).

V. overlap - (See overlap, vertical).


Waxing (waxing-up) - The contouring of a wax pattern or the wax base of a trial denture into the desired tooth and tissue forms.

Functionally generated W. - The prescribing of the occlusal surfaces of the teeth as dictated by the opposing teeth when using the mouth as the articulator; a technique in dentistry generally utilizing wax to determine the functional pathways of opposing teeth for the purpose of fabricating the necessary occlusal anatomy of a waxed tooth.

Wax Additive W. - The technique of forming, by wax additions, the occlusal elevations in a sequence that assures proper occlusal form to obtain the desired contour, occlusion and disclusion.

Wear - A loss of substance or a diminishing through use, friction, etc.

Interproximal W. - The wear of proximal surfaces of the teeth resulting in broader interproximal contacting surfaces and a decrease of the mesiodistal dimension of the teeth and the dentition as a whole.

Occlusal W. - Attritional loss of substance on opposing occlusal surfaces attributed primarily to bruxism.

Pathologic W. - (See abrasion, pathologic).

Physiologic W. - (See abrasion, physiologic).

Wear facet - (See facet, wear).

Wilson curve - (See Curve of Wilson).

Working contact - (See contact, working).

Working side - (See side, working).

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