Compensation trends of the angulation of first molars: retrospective study of 1 403 malocclusion cases

Abstract

Examining the angulation of molars could inform orthodontists about the best way to treat malocclusions, according to a large Chinese study. Malocclusion, or misalignment of teeth, has often been classified based on the position of incisors but molars are arguably more important for maintaining strong tooth anchorage. Tian-Min Xu at Peking University in Beijing and co-workers examined medical records and X-rays from 1, 403 malocclusion patients to extract data on molar angles. The data showed that the upper first molar tended to angle towards the back of the mouth in adolescents but angled forwards in adults. The team also found significant relationships between molar angulation and the relative positions of the maxilla and mandible. This unprecedented dataset should help dental practitioners to understand the long-term effects of orthodontic appliances on tooth anchorage and alignment.

Keywords

Angle classification / angulation / compensation / first molar / growth stages / malocclusion / sagittal skeletal patterns / vertical skeletal patterns

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