AAO - The American Association of Orthodontists is a professional association of educationally qualified orthodontic specialists dedicated to advancing the art and science of orthodontics and dentofacial orthopedics, improving the health of the public by promoting quality orthodontic care, and supporting the successful practice of orthodontics.
ABFRACTION - Loss of tooth tissue not caused by cavities that usually occurs at the gingival margin.
ABRASIVE - Substance used for smoothing or polishing teeth.
ABRASIVE STRIPS- Thin strips that are coated with abrasive particles of different grain size and are used to smooth, polish, and finish tooth contour.
ACRYLIC- Methyl methacrylate, an organic resin often used for the construction of dental appliances, including appliances for active orthodontic tooth movement.
ACTIVATOR- Removable orthodontic appliance that helps growth guidance.
ADHESIVE RESIN- Agent used with composite resins to bond brackets to the tooth structure.
ALVEOLAR BONE- Bone that supports and surrounds the roots of the teeth.
ANCORAGE- A resistance to force that comes from a variety of anatomical components including teeth, bone, soft tissue, and implants.
ANGLE CLASSIFICATION OF MALOCCLUSION-
Class I malocclusion- (neutroclusion) The mesiobuccal cusp of the maxillary (upper) first molar occludes in the buccal groove of the mandibular (lower) first molar. "Class I" is sometimes incorrectly used as a synonym for normal occlusion, whereas it signifies only a normal sagittal relationship of maxillary and mandibular posterior teeth where they meet.
Class II malocclusion- (distoclusion) A posterior)placement of the mandibular (lower) molar, an anterior relationship of the maxillary (upper), or a combination of the two. The mesiobuccal cusp of the maxillary first molar occludes mesial to the buccal groove of the mandibular first molar, usually near the embrasure between the mandibular molar and second premolar.
Class III malocclusion (mesioclusion)- Anterior relationship of the mandibular first molar to the maxillary first molar, a retruded relationship of the maxillary first molar to the mandibular, or a combination of the two. The mesiobuccal cusp of the maxillary first molar will often occlude near the embrasure between the mandibular first and second molars.
ANKYLOGLOSSIA- Attachment of the tip of the tongue to the floor of the mouth or the lingual alveolar ridge, which restricts mobility of the tongue and may lead to speech impediments. This is also called “tongue-tie”.
ANKYLOSIS- Fusion of a tooth to alveolar bone which prevents both eruption and orthodontic movement. In a growing child, an ankylosed tooth can appear to 'submerge' as adjacent unaffected teeth and alveolar bone continue their normal pattern of eruption and growth.
APPLIANCE- Any device designed to influence the shape and/or function of the teeth, jaws, and other oral structures.
Fixed appliance - A bonded or banded appliance affixed to an individual tooth or groups of teeth.
Functional appliance - A device, removable or fixed, designed primarily to effect skeletal and/or dental changes by modifying and utilizing the neuromuscular forces of the stomatognathic system (e.g., activator, bionator).
Orthodontic appliance - A device used to influence the position of teeth and jaws.
Orthopedic appliance - A device used to influence the growth or position of bones.
Removable appliance - A device that can be removed from the mouth and replaced at will by the patient.
ARCH- Collectively, the teeth of either jaw, i.e., the term maxillary arch would include all teeth in the upper jaw arch.
ARCH WIRE- A wire capable of guiding tooth movement that is placed into orthodontic attachment which are affixed to the crowns of two or more teeth.
BAND - A thin metal ring, often stainless steel, which serves to secure orthodontic attachments to a tooth. A band, with orthodontic attachments soldered to it, is closely adapted to fit the contours of the tooth and subsequently cemented into place.
BILATERAL - Relating to both sides of the body.
BIOMECHANICS - Study of mechanical principles applied to biological functions- in the case of orthodontics, oral structures.
BISPHOSPHONATES- A class of drugs that inhibit osteoclast action and the resorption of bone to treat osteoporosis, ostetis deformans, bone metastasis (with or without hypercalcemia), multiple myeloma and other conditions that feature bone fragility.
BITEBLOCK- A orthodontic removable appliance, usually covering the occlusal surfaces of the teeth, used for vertical control or for TMJ problems.
BITEPLATE- A removable orthodontic appliance designed to open the bite and/or prevent specific teeth from occluding.
BOARD CERTIFIED- The status of an orthodontist who has successfully finished both the Written and the Clinical Examination administered by The American Board of Orthodontic.
BONDING- The process by which orthodontic attachments are affixed to the teeth with an adhesive.
Fixed appliance - A bonded or banded appliance affixed to an individual tooth or groups of teeth.
Direct bonding - orthodontic attachments are placed directly on a tooth surface.
Indirect bonding - A two-step process by which orthodontic attachments are affixed temporarily to cast teeth and then transferred to the mouth by means of a molded matrix that preserves their predetermined orientation and permits them to be bonded simultaneously.
BRACES- Fixed devices used in orthodontics that straighten teeth and help position them relative to an individual's bite, while also aiming to improve dental health. They are used to correct underbites, malocclusions, overbites, open bites, deep bites, crossbites, crooked teeth, and various other flaws of the teeth and jaw.
BRACKET- An orthodontic attachment made from metal, ceramic, or plastic that is secured to a tooth (either by bonding or banding) for the purpose of engaging an archwire.
BRUXISM- The parafunctional grinding of teeth (also called tooth-grinding) usually due to an involuntary oral habit.
BUCCAL- Toward the cheeks.
BUCCAL TUBE- A small metal part of the bracket welded to the buccal side of the molar band. The tube may hold an archwire, lip bumper, headgear facebow or other appliances an orthodontist may use to move teeth.
CEPHALOMETRIC RADIOGRAPH - A standardized radiograph of a person’s head characterized by a precisely defined relationship among x-ray source, subject and film.
CEPHALOMETRIC TRACING - A fine line tracing on an acetate film overlay of important cephalometric structures, landmarks and pertinent measurements, used for diagnostic purposes.
CERAMIC BRACES - Crystalline alumina tooth-shade or clear synthetic sapphire brackets that are aesthetically more attractive than conventional metal brackets.
CERVICAL APPLIANCE - Mostly an extraoral appliance that, when activated, delivers responsive force, by means of a pad, placed on the back of the neck.
CHAIN - A stretchable series of connected elastic o-rings that are placed around each bracket to hold the archwire in place and move the teeth.
CHIN CAP - Part of an extraoral orthopedic appliance capable of delivering superiorly and posteriorly directed force to the chin.
CLEFT LIP - A unilateral or bilateral congenital fissure in the roof of the mouth (palate.)
CLEFT PALATE - A unilateral or bilateral congenital fissure in the roof of the mouth (palate.)
CLICKING - A term applied to abnormal soft tissue sounds (usually audible or by stethoscope or upon palpation) emanating from one or both temporomandibular joints during jaw movement.
CLOSED BITE - Excessive vertical overlap of the anterior teeth by the posterior teeth.
COMPREHENSIVE ORTHODONTICS - Coordinated treatment including diagnosis leading to the improvement of a patient's craniofacial dysfunction and/or dentofacial deformity which may include anatomical, functional and/or esthetic relationships.
COMPUTERIZED CEPHALOMETRICS - The process of entering cephalometric data in digital format for analysis by any one of a variety of analyses available in software format.
COMPUTERIZED DIGITAL IMAGING - Substitution of a radiation detector plate for radiographic film inside the film cassette. The detectors store radiation energy at each pixel as a latent image for release into the 13 computer in digital format. Advantages include a radiograph with a much wider dynamic range for improved edge enhancement as well as the ability to change contrast in specific regions.
COSMETIC ORTHODONTICS - Orthodontic therapy for which the purpose is limited to improving the appearance of the teeth or face.
CROSSBITE - An abnormal relationship of an individual tooth or teeth to the opposing teeth, in which normal buccolingual or labiolingual relationships are reversed.
CROWDING - Malalignment of teeth caused by inadequate space for the teeth.
CURVE OF SPEE - The anatomic curve established by the occlusal and incisal surfaces of the tooth crowns, as projected into the median plane in either of the dental arches. The curve is generally concave upward in the mandibular arch and convex for the maxillary arch.
CURVE OF WILSON - Because the long axes of the mandibular molars and premolars converge towards the midline, the occlusal surfaces of these teeth bilaterally, form a curve in a buccolingual direction.
DEBANDING - The removal of cemented orthodontic bands.
DEBONDING - The removal of bonded orthodontic attachments.
DECOMPENSATION - Orthodontic tooth movement done to bring teeth into optimum position in their respective jaws in preparation for orthognathic surgery.
DEMINERALIZATION - A loss of calcium from the hydroxyl-apatite crystals, which leaves teeth more vulnerable to further bacterial attack.
DDS OR DMD - two equivalent doctorate degrees awarded by dental schools to graduates of the doctoral dental program.
DEEP BITE - Excessive overbite.
DEHISCENCE - A fissural defect of the facial alveolar plate extending from the free margin apically.
DENTAL PLAQUE - A “conglomeration” of bacteria and organic matter which adheres to teeth and related structures.
DENTIN - The hard tissue of the tooth surrounding the central core of nerves and blood vessels (pulp) which forms the bulk of a tooth and is covered by enamel on the coronal part and cementum on the radicular portion of the tooth.
Fixed appliance - A bonded or banded appliance affixed to an individual tooth or groups of teeth.
Primary dentition - Often called baby-teeth, these are teeth that develop and erupt first in order of time and are normally shed and replaced by permanent (succedaneous) teeth.
Transitional dentition - A phase in the change from primary to permanent dentition and having characteristics of both, in which the primary molars and canines are in the process of exfoliating and the permanent successors are emerging.
Adolescent dentition - The dentition present after the normal loss of primary teeth and prior to cessation of growth that could affect orthodontic treatment.
Adult dentition - The dentition present after the cessation of growth that could affect orthodontic treatment.
DENTOFACIAL DEFORMITY - Malformation of dental and/or facial structures characterized by disharmonies of size, form and function, malocclusion, cleft lip and palate and other skeletal or soft-tissue deformities, including various types of muscular dysfunction.
DIAGNOSTIC SET UP - Procedure in which teeth are removed from a plaster cast and repositioned in wax. It can be used as a diagnostic tool to evaluate alternative treatment plans, particularly in interdisciplinary treatment, when a tooth size discrepancy exists or when orthognathic surgery is required along with orthodontic treatment.
DIASTEMA - A space or gap between two adjacent teeth in the same dental arch.
DISCREPANCY- A disparity in the ratio of tooth size to arch length in the mouth.
DISTAL - A direction oriented along the dental arch away from the dental midline or body’s center.
DOLICHOCEPHALIC - Long and narrow cranial form and the opposite of brachycephalic.
DOLICHOFACIAL - The anatomic curve established by the occlusal and incisal surfaces of the tooth crowns, as projected into the median plane in either of the dental arches. The curve is generally concave upward in the mandibular arch and convex for the maxillary arch.
DYSFUNCTION - Abnormal function or partially impaired.
DYSPLASIA - Abnormality in development of tissue or organ.
EARLY ORTHODONTIC TREATMENT - Orthodontic treatment that is started while the patient is still in the transitional or primary dentition.
EDGE-TO-EDGE OCCLUSION - An occlusion often associated with a Class III molar relationship in which the anterior or posterior teeth of both jaws meet along their incisal or buccal cuspal edges.
EDGEWISE APPLIANCE - A fixed appliance characterized by attachment brackets that have a rectangular slot for engagement of a rectangular orthodontic wire.
ELASTICS - Bands usually made of latex that are worn to provide individual tooth movement or jaw alignment.
ELASTOMERIC LIGATURE - A polymeric,rubber band, or thread that is stretched around the tie-wings of an orthodontic bracket for the purpose of preventing disengagement of an archwire or auxiliary from the bracket-slot.
EMBRASURE - The space formed around the adjoining contact of two teeth.
ENAMEL - The hardest material in the human body and is a thin, translucent layer of calcified tissue that surrounds the dentin in the coronal part of the tooth.
ENAMELPLASTY - Often done as occlusal adjustment, reshaping of the enamel.
ERUPTION - Movement of teeth in an incisal or occlusal direction into the oral cavity through the gingival tissue and supporting bone.
EXPANSION - Used to describe the mechanical widening of the dental arches and simply means enlarging.
EXPANSION SCREW - A mechanical device incorporated in a removable or a fixed appliance that is used to expand the dental arch in some dimension.
EXTRA ORAL - Outside of the mouth.
EXTRACTION - Removal of a one or more teeth.
EXTRUSION- A translational form of partial tooth displacement with movement occlusally directed and parallel to the long axis of the tooth.
FACIAL ASYMMETRY - In the negative sense, a term used to describe a reduction of similarity or proportion between the right side and left side of the face or the craniofacial skeleton. Can also be applied to any structure that is too large or small so as to be out of balance or not proportional to other structures.
FACIAL CONCAVITY - A term applied to the analysis of a human profile. The shape is described as an inwardly rounded curve from the forehead to the lips to the chin and a concave facial profile is often associated with a Class III malocclusion.
FACIAL CONVEXITY - A term opposite to facial concavity, describing an outwardly rounded curve from the forehead to the lips to the chin. A convex facial profile indicates a fullness in the lip region and is associated with a Class II malocclusion.
FACIAL ESTHETICS - Pertaining to facial symmetry, beauty, balance, and proportion.
FACIAL FORM - The configuration, shape, or appearance of the face from a frontal view.
FACIAL GROWTH - The process of enlargement of soft tissues and the craniofacial skeleton.
FACIAL PROPORTIONS - An assessment of the balance of the face from a frontal or profile view. The intent of the assessment is to determine asymmetry or imbalance.
FACIAL TYPE - A classification of the face with 3 types described: brachycephalic or euryprosopic (wide, short), dolichocephalic, or leptoprosopic (long, narrow), and mesocephalic or mesoprosopic (average).
FINISHING - A stage of treatment toward the end of comprehensive orthodontic care in which the teeth are placed in their final positions.
FIXED APPLIANCE - An orthodontic appliance whose attachments are bonded or cemented to the teeth and cannot be removed by the patient with one type usually referred to as braces.
FREE-WAY SPACE - The distance between the maxillary and mandibular teeth when the mandible is in its resting position.
FRENECTOMY - The surgical removal or repositioning of a frenulum to enhance the stability of a corrected diastema or to alleviate a “tongue-tie”.
FRENULUM / FRENUM - A fold or ridge of mucous membrane and underlying fibrous tissue that connect lip, cheek or tongue to the alveolar mucosa. (May be labial or lingual).
FUNCTIONAL OCCLUSION- An arrangement of the teeth that is intended to minimize stress on the temporomandibular joint; maximize function, stability and esthetics of the teeth; and provide for protection and health of the periodontium.
GENIAL - Relating to the chin.
GENIOPLASTY - A surgical procedure designed to reshape the contour of the chin via by augmentation or reduction.
GINGIVA - Colloquially referred to as the gums, fibrous investing tissue, covered with epithelium, which immediately surrounds the teeth and is contiguous with the periodontal ligament and with the mucosal tissues of the mouth.
GINGIVAL ATTACHMENT - The fibrous attachment of the gingiva to the teeth.
GINGIVAL GRAFT - A surgical procedure usually performed to establish an adequate amount of attached gingiva around one or more teeth.
GINGIVAL RECESSION - Shift of the gingival edge apically so that part of the root of the tooth is exposed.
GINGIVITIS - Inflammation of the gingiva.
GRAFT - A portion of tissue that is used for implantation.
GROUP FUNCTION - Multiple simultaneous contacts of several maxillary and mandibular teeth on the working side in functional movement of the mandible during which forces are distributed on a number of teeth.
GROWTH FORECAST - A educated estimation of change in the location or size of the bones of the craniofacial skeleton due to expected growth and development and/or the effects of treatment.
GUIDE PLANE - A fixed or removable orthodontic appliance designed to deflect the functional path of the mandible and alter positions a single tooth, an arch segment, or an entire arch.
GUMMY SMILE - A colloquial term for excessive exposure of maxillary gingival tissue during a full smile.
HABIT - In dentistry, a term applied to frequently repeated negative activity such as finger/lip sucking or tongue thrusting that may alter the normal development of the teeth or bones.
HAWLEY APPLIANCE - A Hawley retainer that has been modified to allow for minor corrective procedures.
HAWLEY RETAINER - A passive removable acrylic and wire appliance, used to stabilize teeth in their new position after orthodontic correction.
HEADCAP - The component of an (primarily) extraoral appliance that distributes and transfers responsive force to the head.
HEADGEAR - Common generic term for an extraoral traction appliance that can be used for growth modification, anchorage, and tooth movement.
HERBST APPLIANCE - Much like an activator, a fixed or removable appliance designed to effect an orthopedic change of the mandible.
HYPODONTIA - Congenital absence of one or more teeth (excluding the third molars) .
HYPOPLASIA - Incomplete development of a tissue or organ.
IMAGING - The process of acquiring representations of structures like teeth and bone, in either two or three dimensions.
IMBRICATION - An overlap of canines and incisors due to crowding.
IMPACTION - A condition that describes the partial or total lack of eruption of a tooth well after the normal age for eruption.
IMPLANT - Either a graft placed into soft tissue, or an artificial structure placed into bone which provides for prosthetic replacement of some missing structure.
IMPRESSION - When an elastic compound like alginate is placed into a preformed tray, the loaded tray is then placed over the teeth until the material stiffens and then it may be filled with plaster to produce an exact positive reproduction of the teeth or dental arch.
INFECTION CONTROL - Guidelines set forth by the CDC or OSHA which are practiced by personnel in healthcare and dental facilities to decrease transmission and acquisition of infectious agents (e.g., proper hand hygiene, scrupulous work practices, use of personal protective equipment (PPE) [masks or respirators, gloves, gowns, and eye protection].
INFORMED CONSENT - An agreement by the patient or parent/guardian of the patient to proceed with or decline treatment after the benefit and risks of treatment options have been presented.
INTERCEPTIVE ORTHODONTICS - An extension of preventive orthodontics that may include localized tooth movement as soon as the malocclusions are detected.
INTERDENTAL SPACING - Spacing between the teeth.
INTERMITTENT FORCE - An orthodontic force that is inactive for intervals of time during the between-appointments period, often exhibiting a cyclic, long-term, magnitude-time pattern (e.g., force exerted by an extraoral appliance worn only at night).
INTRAORAL - Inside of the mouth.
INVISALIGN - A technology used only in minor cases that is developed using computer scanners and virtual reality to move teeth gradually using the construction of clear overlay retainer appliances.
JAW - A common term for either the maxilla (upper) or mandible (lower).
JAW RELATIONSHIP - The position of the maxilla in relationship to the mandible; usually an anteroposterior or transverse assessment.
LABIAL - Relating to the lip, a term that describes a tooth surface facing the lips and has the same meaning as 'facial' in the anterior portion of the dentofacial complex.
LEEWAY SPACE - The difference between the combined widths of the three buccal primary teeth (canine and first and second molars) and their permanent successors (canine and first and second premolars).
LE FORT SURGICAL PROCEDURE - Surgical jaw procedure in which parts of the upper face are completely separated from their supporting structures and repositioned to effect corrective alignment.
Le Fort I surgical procedure - A horizontal segmented fracture of the alveolar process of the maxilla, in which the teeth are usually contained in the detached portion and used to treat upper jaw malocclusion and cleft palate.
Le Fort II surgical procedure - Involves movement of the nose and upper jaw together due to a pyramidal fracture of the midfacial skeleton with the principal fracture lines meeting at an apex of the superior aspect of the nasal bones.
Le Fort III surgical procedure - Movement of the entire face forward due to a craniofacial dysjunction fracture in which the entire maxilla and one or more facial bones are completely separated from the cranial base.
LEVELING - To align the teeth in the same plane also known as a phase of comprehensive orthodontic treatment when fixed appliances are used to change the line of intercuspation from a curve to a straight line.
LIGATION - The act of tying or of applying a ligature. In orthodontics, used to denote tying a wire to the orthodontic brackets.
LIGATURE - A tie that secures the archwire in the bracket-slot typically rubber, a polymer, or wire that has been heated and then cooled to decrease brittleness.
LIGHT-WIRE TECHNIQUE - An orthodontic treatment in which small force values, active over long time periods are used and the appliance components to be activated are relatively flexible.
LIMITED ORTHODONTICS TREATMENT - Typically focuses on limited corrective objectives, not necessarily involving the entire dentition. Can be directed at the only existing problem, or at only one aspect of a larger problem in which a decision is made to defer or forego a more comprehensive plan of therapy.
LINGUAL - Related to the tongue. A term used to describe surfaces and directions facing toward the tongue.
LINGUAL APPLIANCES - Orthodontic appliances fixed to the lingual surface of the teeth.
LINGUAL ARCH - A single wire, that traverses the lingual surfaces of the teeth, usually from molar to molar that is generally used for stabilization, as a holding arch for space maintenance, for expansion, or to provide anchorage for intermaxillary traction.
LIP BUMPER - An appliance designed to eliminate excessive lip pressure on the anterior teeth from soft tissue and transfer that force to the molars. Typically consists of a labial archwire with or without an anterior pad made of plastic, fitted into tubes on the molars.
LIP INCOMPETENCE - A gap between the relaxed upper and lower lips because of a vertical hard and soft tissue imbalance, showing strain in the muscles around the face when a lip seal is attempted.
LONG FACE SYNDROME - Potentially thought be the result partly from lack of an adequate airway, a craniofacial pattern characterized by a long and narrow face, an increased mandibular plane angle, an anterior open bite malocclusion and lip incompetence.
MACRODONTIA - Abnormally large teeth.
MALOCCLUSION - Often associated with other dentofacial deformities, a deviation in intramaxillary and/or intermaxillary relations of teeth from normal occlusion. See Angle classification for more detail.
MANDIBLE - The bone of the lower jaw.
MANDIBULAR OSTEOTOMY - Surgical cutting, moving, or modifying of bone of the mandible into two or more parts to allow repositioning of the resulting components.
MASTICATION - The process of crushing food by chewing for swallowing and digestion
MAXILLA - The bone of the upper jaw that form the base for the upper dental arch, floor of the nose and much of the lower border of the orbit and cheek bones.
MAXILLARY - Relating to the upper jaw.
MAXILLARY OSTEOTOMY - Surgical cutting, moving, or modifying of maxillary bone structure to alter bone and jaw relationships.
MAXIMUM FORCE - An orthodontic force having the greatest magnitude that will produce tooth movement at a clinically acceptable rate.
MESIAL - Toward or facing the midline of the face, following the dental arch. Used as a direction as well as surfaces of teeth.
MICRODONTIA - Abnormal small teeth.
MICROGNATHIA - Abnormally small jaw.
MIXED DENTITION - The developmental stage, usually around 6 to 12 years of age, during which both primary and permanent teeth are present in the mouth.
MOUTHGUARD - A removable plastic appliance used to protect the teeth and supporting tissues during contact sports.
MS - Master of Science, a degree awarded by a university graduate school after completion of an advanced dental specialty program.
OCCLUSION - The relationship of the maxillary and mandibular teeth as come together into functional contact.
OCCLUSAL PLANE - The imaginary surface on which maxillary and mandibular teeth meet in occlusion. It is actually a compound curved surface, but is commonly approximated by straight line from the side view based on specific reference points within the dental arches.
OPEN BITE - Malocclusion which involves no vertical overlap or contact between anterior teeth in an occluding position.
ORTHO - A prefix denoting straight, upright, or correct.
ORTHOGNATHIC SURGERY - Usually accomplished in conjunction with orthodontic therapy, surgery to alter relationships of teeth and/or supporting bones.
ORTHOPEDIC - Correction of abnormal form or relationship of bone and associated structures. May be accomplished surgically or by the application of appliances to stimulate changes in the bone structure by natural physiologic response.
ORTHOGENESIS - Development or formation of bone.
OVERBITE - Vertical overlap of upper teeth over lower front teeth in the normal occlusal plane.
OVERJET - Horizontal projection of upper teeth beyond the lower front teeth in the normal occlusal plane.
PALATE - The bone and soft tissue that forms the roof of the mouth separating the cavities of the nose and the mouth.
PALATAL EXPANSION - Enlarging of the maxillary dental arch and the palate to increase palatal width.
PANORAMIC RADIOGRAPH - A radiograph of the jaws, taken with a specialized machine designed to present a panoramic view (from ear to ear) of the full circumferential length of the jaws on a single film.
PERIAPICAL - Pertaining to the area and tissues around the apex of the root of a tooth.
PERIODONTAL MEMBRANE - The fibrous tissue around teeth that occupies the space between tooth root and alveolar bone which provides a physical attachment of the tooth to the bone and nourishment to the surface of the root and the cells that permit tooth movement.
PULP - The soft tissue consisting of specialized loose connective tissue, blood vessels and nerves occupying the inner chamber of a tooth.
RADIOGRAPH - A permanent image, typically on film, produced by x-rays, gamma rays, or similar ionzing radiation.
REPROXIMATION - In order to reduce combined tooth width, abrasive elimination of small amounts of enamel from the proximal surfaces of the teeth.
RESORPTION - Physiologic or pathologic removal of hard, mineralized tissue like bone or root.
RETAINER - A fixed or removable appliance that is used to maintain the position of the teeth following corrective treatment.
ROOT - The part of the tooth not covered by enamel that normally lies within the alveolus where it is attached to the bone by the periodontal membrane (ligament).
SELF LIGATION - A permanent image, typically on film, produced by x-rays, gamma rays, or similar ionzing radiation.
SEPERATOR - An object or agent (elastic module, brass wire, spring) used for separating teeth.
SERIAL EXTRACTION - A program of selective or guided extraction of primary and sometimes permanent teeth over a period of time, with the objective of relieving crowding and facilitating the eruption of remaining teeth into corrected positions.
SINUS - Air cavities within the facial bones or other tissue, lined by mucous membranes similar to those in other parts of the airways.
SPACE MAINTAINER - An orthodontic appliance prosthetic replacement for prematurely lost primary teeth intended to prevent closure of the space before eruption of the permanent successors.
SUPERNUMERARY TEETH - Teeth, often malformed or erupting abnormally, that are in excess of the normal number.
SUPRACRESTAL FIEROTOMY - The procedure of severing the gingival fibers from the tooth; used as an aid to retain the correction of rotation.
TEMPORARY ANCHORAGE DEVICE - A temporarily device fixed to bone for the purpose of enhancing orthodontic anchorage either by supporting the teeth of the reactive unit or by obviating the need for the reactive unit altogether, and which is subsequently removed after use.
TINNITUS - Noise in the ears, such as buzzing, ringing, roaring, clicking that is often a symptom reported in TMJ dysfunction problems.
THERAPEUTIC DIAGNOSIS - An assessment of the objectives and available methods of treatment in light of conditions existing in a patient.
THUMB SUCKING - A normal infantile activity that sometimes extends into middle or late childhood that may produce or exacerbate malocclusion.
TMD - Temporomandibular dysfunction.
TMJ - One of the two paired articulations that hinges the temporal bones of the skull and the mandible.
TONGUE CRIB - An appliance used to control undesirable and potentially deforming tongue movements, i.e., viseral swallowing or thrusting of the tongue between the front teeth.
TONGUE THRUST - The positioning of the tongue between the front teeth, especially in the initial stage of swallowing which often combined with a resting position of the tongue between the teeth, can inhibit normal eruption and produce an open bite.
TOOTH SIZE DISCREPANCY - Relative spacing or crowding in different parts of the dentition caused by lack of proportional harmony in the width of various tooth crowns and the available space in the dental arch.
TRAUMA - In dentistry, tissue damage caused by an external force, such as a blow in an accident or abnormal clenching or grinding of the teeth.
UNDERBITE - An non-technical term for negative overjet, or when the lower anterior teeth are positioned in front of the upper anterior teeth when biting.
UNILATERAL - Relating to only one side.
WAX - Thermoplastic materials which are solids at room temperature that can be placed on the brackets or archwires to prevent them from irritating the lips or cheeks.
WAX BITE - An impression made by closing the teeth on modeling composition or wax.