Personal identification by morphometric analyses of intra-oral radiographs of unrestored teeth*

The aim of this study was to work out a biometric method for personal identification by comparing simulated antemortem and postmortem digital radiographs of unrestored teeth. Intra-oral radiographs of the inferior right first molar, without restorations, were acquired at two different times in 70 subjects using a standardized technique followed by a morphometric analysis. The program automatically supplied values of the absolute distances, relative distances, shape factors, moments, perimeter values, and the areas of the triangles, which were obtained by joining key reference points. The values for the homologous samples were compared with the heterologous samples. Statistical analysis was then carried out, resulting in a section point value of 0.9992. Higher correlation coefficients indicate positive identification, with less than 2% risk of false positives, and approximately 3% of false negatives. We have also tested the method on dental records from 30 patients in order to demonstrate the specificity and sensitivity of the system.