Classification and Terminology of Malocclusion

Angle’s Class I (Neutroclusion)

Triangular ridge of the mesiobuccal cusp of the maxillary first permanent molar articulates in the buccal groove of the mandibular first permanent molar.

Class I, Type 1

Crowded anterior teeth

Class I, Type 2

Maxillary incisors in labioversion

Class I, Type 3

Anterior crossbite (maxillary anteriors are in linguoversion)

Class I, Type 4

Posterior crossbite

Class I, Type 5

Mesial drifting of permanent molars

Angle’s Class II (Distoclussion)

The mesial groove of the mandibular first permanent molar articulates posteriorly to the mesiobuccal cusp of the maxillary first permanent molar

Class II, Division 1

Distoclusion in which the maxillary incisors are typically in extreme labioversion

Class II, Division 2

Distoclusion in which the maxillary central incisors are near normal anteroposteriorly or slightly in linguo- version, whereas the maxillary lateral incisors have tipped labially and mesially

Class II, Subdivisions

When the distoclusion occurs on one side of the dental arch only, the unilaterality is referred to as a sub-division of its division.

Angle’s Class III (Mesioclusion)

The mesial groove of the mandibular first permanent molar articulates anteriorly to the mesiobuccal cusp of the maxillary first permanent molar

Class III, Type 1

Edge-to-edge incisor bite

Class III, Type 2

Mandibular incisors are crowded and in linguovesion

Class III, Type 3

Maxillary incisors are crowded and in crossbite

Protraction

When the dental arch, or part of it, is more anteriorly placed than normal with respect to the orbital plane

Retraction

When the arch, or part of it, is more posteriorly placed than normal with respect to the orbital plan

Contraction

When the dental arch, or part of it, is nearer to the midsagittal plane than the normal position

Distraction

When the arch, or part of it, is farther away from the midsagittal plane than the normal position

Attraction

When the dental arch, or part of it, is nearer to the Frankfurt plane than the normal position

Abstraction

When the dental arch, or part of it, is farther away from the Frankfurt plane than the normal position

Mesioversion

mesial to the normal position

Distoversion

distal to the normal position

Linguoversion

lingual to the normal position

Labioversion or buccoversiom

toward lip or cheek

Infraversion

away from the line of occlusion

Supraversion

extended past the line of occlusion

Axiversion

tipped; wrong axial inclination

Torsiversion

rotated on its long axis

Transversiom

Wrong order in the arch; transposition

Deep overbite

excessive vertical overlap of the incisors

Open bite

there is localized absence of occlusion while the remaining teeth are in occlusion

Crossbite

abnormal buccolingual (labiolingual) relationship of the teeth

Align,ent

Intra arch; crowding, spacing, or ideal alignment

Profile

convex, straight, or concave

Transverse (crossbite)

buccolingual discrepancies

Sagittal

anterior-posterior

Vertical

bite depth (open or deep bite)