Kanavakis G, Alamoudi R, Oeschger E S, Tacchi M, Halazonetis D, Gkantidis N. Third molar agenesis relates to human craniofacial form. Eur J Orthod 2023; DOI: 10.1093/ejo/cjad057.

There is a strong association between third molar formation and craniofacial shape.

This study investigated the association between the number of third molars and craniofacial shape. The sample comprised 470 individuals out of whom 310 had a full permanent dentition including third molars and 160 had at least one missing third molar. Pre-orthodontic treatment cephalometric images were digitised using 127 landmarks to describe the shape of the entire craniofacial configuration, the cranial base, the maxilla, and the mandible. The shapes of the various configurations were described by principal components (PCs) of shape. There was a strong association between third molar agenesis and the shape of all craniofacial configurations in both sexes. Individuals with missing third molars presented a less convex craniofacial configuration, a shorter anterior facial height and a more retrusive maxilla and mandible. In cases with third molar agenesis only in one jaw, shape differences were also evident in the opposing jaw.