Application of optical dental impression data for personal identification

Abstract

The identification of corpses is according to physical characteristics. Among these, teeth are often used for personal identification because they are insusceptible to post-mortempostmortem alterations. Recently, different types of digital data, like optical impressions, have been employed in dentistry. This research identified three indices on the teeth of Standard Triangled Language (STL) data collected using optical impression-taking and evaluated the possibility of personal identification by examining the area of the triangle obtained from three indices. STL data generated from intraoral plaster models (n ＝140) were fabricated virtual antemortem (VAM) data. STL data collected directly from the intraoral cavity (n ＝24) were employed as virtual post-mortempostmortem (VPM) data. Three indices were identified for each first premolar, second premolar, and first molar. Two techniques were devised to find the three points. The area of the triangle created utilizing the three measurement points were employed to assess the conditions under which each VPM data could be excluded from the VAM data group. Although no significant difference existed between the two techniques, one method was preferred for screening. Optimal conditions for both methods were screening carried out with two teeth, including the second premolar. In both methods, only the individual was screened out of 140 individuals when the second premolar was added in the two-teeth condition. This study demonstrated the possibility of personal identification by assessing the area obtained using three measurement points on teeth as indices, indicating a potential application in forensics in the future.