Abstract
Surgical alterations of the face have been shown to be a defining factor in alterations of physical appearance. It is estimated that 5% of the population undergo corrective procedures of the jaws for aesthetic or health purposes.
To date, however, practitioners have been lacking guidelines specifying the way facial identification should be conducted. The present study explores the effect of oral and maxillofacial surgeries on landmark-based algorithms when conducted on 3D imagery.
The sample composed of 50 pre-op and post-op 3D face images of individuals who had undergone corrective surgeries was tested against a set of 500 faces from the general European population. An approach based on discrete points was employed while the number of landmarks was gradually reduced to minimize intra-person and maximize inter-person variance.
The results showed that the presence of surgical modifications resulted in misclassifications based on the mid-face and lower face features, particularly upper lip protrusion and shape, lower lip protrusion, and chin protrusion. The optimal set of landmarks which avoided the surgically affected regions reached an accuracy of 92% at the rank of 1% and 98% at the rank of 5.
Across all tested landmark configurations, males were consistently less prone to mismatches than females.