Determining the genuine and the imposter pair of the dental arch pattern through the 3D point cloud analysis for forensic identification

Objective. The objective of this study was to investigate the efficient parts of the dental arch for human identification. Materials and Methods. A total of 120 pairs of superimposed 3D point cloud data of dental casts that met the inclusion criteria were involved in this study. Rapidform XOS/SCAN (INUS Technology, Inc., South Korea) software was used to create the group for 3D data superimposition as follows: anterior teeth (A), right and left side (B), and posterior teeth (C), six teeth were involved in each group. The corresponding dental arch segments were registered in 3D space and the resulting Root Mean Square Errors (RMSE) were evaluated using MATLAB (The MathWorks, Inc., USA). Statistical analysis. Statistical analysis was conducted using ANOVA test and multiple comparison post hoc test. Results. The result of the ANOVA test showed that the RMSE discrepancies were not significant among these three groups. Multiple comparison post hoc test results indicate that there was no significant difference in the RMSE value between groups A and B, p>0.05. However, the difference was significantly observed when comparing group C to group A and B, p<0.05. Conclusion The result of this study suggests some information that can be considered in forensic dental identification. First, the RMSE value between the genuine and the imposter pairs was influenced by how many teeth were involved in the superimposition. Second, the difference was clearer when superimposing two bilateral dental arches rather than the unilateral arch. Third, the anterior teeth have sufficient performance as a parameter for dental identification.