Angle's classification
What you need to know
- Class I: the mesiobuccal cusp of the upper first molar sits in the buccal groove of the lower first molar. Heads up: there can still be crowded teeth; Class I isn't the same as a perfect bite.
- Class II (distocclusion): the groove of the lower molar sits behind (distal to) that upper cusp.
- Class II, division 1: the upper incisors are tilted forward (proclined).
- Class II, division 2: the upper central incisors are tilted backward (retroclined), often with a deep bite.
- Class III (mesiocclusion): the groove of the lower molar sits in front of (mesial to) that upper cusp.
- Angle published it in 1899 and it's still the most widely used classification. It only describes the front-to-back relationship.
Terms in plain words
Mesiobuccal cuspThe cusp at the front and on the outside of the upper first molar.
Buccal grooveThe groove on the outer surface of the lower first molar, between its buccal cusps.
Proclined / retroclinedTilted forward / tilted backward.
For the exam
The buccal groove of the lower molar sits in front of the upper mesiobuccal cusp. Which class is it?
Show answerHide answer
Class III (mesiocclusion).
Sources
- Agarwal N, et al. Dewey's Modification for Angle's Class I Malocclusion: Revisited. Cureus. 2024;16(2):e53490. View source
- Pathognomonic features of Angle's Class II division 2 malocclusion: a comparative cephalometric and arch width study. View source
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