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Orthodontist

A dental specialist who has completed an advanced post-doctoral course, accredited by the American Dental Association, of at least two academic years in the special area of orthodontics.

Orthognathic surgery

Surgery to alter relationships of teeth and/or supporting bones, usually accomplished in conjunction with orthodontic therapy.

Overbite

Vertical overlap of maxillary teeth over mandibular anterior teeth, usually measured perpendicular to the occlusal plane.

Overjet

Horizontal projection of maxillary teeth beyond the mandibular anterior teeth, usually measured parallel to the occlusal plane. When not otherwise specified, the term is generally assumed to refer to central incisors and is measured from the labial surface of the mandibular tooth to the lingual surface of the maxillary at the level of the edge of the upper incisor. Unique conditions may sometimes require other measuring techniques