Forensic Summary by Emma-Rae Ranger
Forensic facial approximation is the application of clay to a skull or a replica of the skull in order to produce an approximate image of the individual. There are three common approaches used for the approximation: anatomical method, tissue depth method, and combination method. Anatomical method involves modeling the facial muscles on the skull. This is generally predicated on the origins and insertions of the facial muscles on the skull. Tissue depth method involves the use of facial thickness averages. This method is generally more favored by law enforcement because of the already published data on facial thickness. The third and final method, the combination method, combines facial muscle and tissue depth (facial thickness). Using any of these methods does not show the overall shape of the face, but rather a relationship between the features.
Three of the most important features for human recognition are the eyes, mouth, and nose. There is a great deal of speculation on how the nose should be reconstructed. This is due to the direct effect that age has on the nasal passages. There are two dimensional and three dimensional analyses. Using the Gerasimov two tangent method, 66 cranial CT scans were examined to see if the method of comparison was statistically accurate. Upon running multiple ANOVA scenarios, the resulting conclusion was that the method, even with revisions was not statistically accurate.
Maltais Lapointe, G., Lynnerup, N. and Hoppa, R. D. (2016), Validation of the New Interpretation of Gerasimov’s Nasal Projection Method for Forensic Facial Approximation Using CT Data,. J Forensic Sci, 61: S193–S200. doi:10.1111/1556-4029.12920