Automated Neoclassical Vertical Canon Validation in Human Faces with Machine Learning

The proportions defined by the neoclassical canons for face evaluation were developed by artists and anatomists in the 17th and 18th centuries. These proportions are used as a reference for planning facial or dental reconstruction treatments. However, the assumption that the face is divided vertically into three equal thirds, which was adopted a long time ago, has not been verified yet. We used photos freely available online, annotated them with anthropometric landmarks using machine learning, and verified this hypothesis. Our results indicate that the vertical dimensions of the face are not always divided equally into thirds. Thus, this vertical canon should be used with caution in cosmetic, plastic, or dental surgeries, and reconstruction procedures.