Novel approach for forensic dental identification using maxillary homologous models

As three-dimensional (3D) intraoral scans are becoming popular in modern dentistry, they also offer a new category of antemortem data for forensic identification. This study proposes a novel methodology for individual identification based on 3D homologous models of the maxilla.

Data from 100 maxillary plaster casts (40 monozygotic twin casts, 28 dizygotic twin casts and 32 singleton casts) were used. From the initial sample, 10 casts were randomly chosen and duplicated four times, resulting in 40 duplicates. These were divided into four groups and subjected to the following alterations: molar attrition (n = 10), canine attrition (n = 10), molar and canine attrition (n = 10), and no alteration (n = 10). All the casts were converted to 3D models and then to homologous models using a template with 24 landmarks. The 3D coordinates of each vertex in the homologous model were then calculated and used for statistical comparison of similarity between two given homologous models using the average Hausdorff distance.

All four groups achieved accurate matching with their original maxillary casts, with a minimal average Hausdorff distance.

This method accurately identified individuals, including monozygotic twins, and exhibited robustness against minor tooth attrition, demonstrating its feasibility as an identification method in actual forensic settings.