Quantifying the asymmetries of the human face.

Abstract

Asymmetries in the human face are quite common but do not get enough attention with regard to forensics and criminalistics. A face with asymmetries has a higher recognition value than a face without such morphological deviations. Therefore it is useful to determine the frequency of facial asymmetries to be able to evaluate the individual asymmetries focusing their rarity. This can be used primarily in forensic anthropology, particularly in the identification of persons. This aspect is the basis of this study. Therefore several structures in the faces of 130 volunteers (65 male, 65 female) from southern Germany were examined for asymmetries based on 3D laser scans. The study showed that asymmetries frequently occur in the eyes, the mouth and the ears. Rarer are asymmetries in the bridge of the nose and the shape of the chin. There is also considerable variation in the degree of asymmetry. Basically it can be said that small-scale structures, such as those in the eye area, have less pronounced asymmetries than large-scale structures such as the nose, mouth, chin and ear.