Use of intraoral three-dimensional images for the identification of dental morphological traits related to ancestry estimation

A new approach for sex prediction by evaluating mandibular arch and canine dimensions with machine-learning classifiers and intraoral scanners (a retrospective study)

In circumstances where antemortem information concerning the deceased individual is unavailable, forensic experts prepare biological profiling for unidentified human remains that aids in narrowing the search for identity. Biological profiling includes basic demographic information such as sex, age, stature, and ethnicity. Sex identification is the first and key step in the biological profiling of unidentified human remains, as it effectively reduces potential matches by excluding nearly one-half of the suspected cases and facilitates the subsequent stages. This study was conducted to assess the accuracy of artificial intelligence (AI) in predicting sex by analysing mandibular canine dimensions, mandibular intercanine distance (MICD), and mandibular canine index (MCI) obtained from three-dimensional (3D) digital impressions captured by using an intraoral scanner (IOS). The results of the receiver operating characteristic (ROC) test indicated that mean mandibular canine width (MeanMCW) had the highest sexual dimorphism with the area under the curve (AUC) of 0.912, and the Gaussian Naive Bayes (GNB) classifier demonstrated the highest testing accuracy among all machine learning (ML) models, achieving an accuracy of 92.5%. While the outcomes of this study are promising, further studies are imperative to validate these findings with larger sample sizes in different ethnic populations.

Digital intraoral and radiologic records in forensic identification: Match with disruptive technology

While clinical dentistry has seamlessly integrated the digital revolution, there is a gap in the technological capabilities of forensic dentistry.The study aimed to compare the superimposition accuracy of two different three-dimensional record formats, namely the intraoral scanner and cone beam computer tomography, in the context of forensic identification.The sample consisted of randomly selected adults (n=10) of both sexes aged between 20 and 50 years. Following the acquisition of data using the Medit i700 wireless scanner and the iCAT Tomograph with InVivo software, the records were analysed and compared through superimposition using Medit Scan Clinic software to assess the technical precision of anatomical identification details.The results obtained through the superimposition of dental and bone records following intra- and inter-observer analysis enabled an accurate comparison and identification of an individual. This method can differentiate between positive and negative matches, achieving exclusion results and offering a potential solution to overcoming the absence of a standardisation procedure in human identification.

Quantitative and qualitative evaluation on the accuracy of three intraoral scanners for human identification in forensic odontology

The purpose of this study was to analyze the accuracy of intra oral scanner (IOS) to confirm the applicability of IOS for the recording and analysis of tooth morphology in forensics. The less damaged mandible specimen with many teeth remaining was scanned three times using three types of intraoral scanners (CS3600, i500, and Trios3). For quantitative comparisons of the scanned images produced by these intraoral scanners, root mean square (RMS) values were computed using a three-dimensional analysis program and a one-way ANOVA was conducted with Tukey HSD (honestly significant difference) as a post-hoc analysis (α=0.05). The repeatability of the full scan data was highest with the i500 (0.14±0.03 mm), and the post-hoc analysis confirmed significant differences between the CS3600 and the i500 outcomes (P-value=0.003). The repeatability of the partial scan data for the teeth in the mandible was highest with the i500 (0.08±0.02 mm), and the post-hoc analysis confirmed significant differences between the CS3600 and the i500 (P-value=0.016). The precision of the full scan data was highest with the i500 (0.16±0.01 mm) but the differences were not statistically significant (P-value=0.091). Meanwhile, the precision of the partial scan data for the teeth in the mandible was highest with the Trios3 (0.22±0.02 mm), but the differences were not statistically significant (P-value=0.762). Considering that the scanning of other areas of the oral cavity in addition to the teeth is important in forensic odontology, the i500 scanner appears to be the most appropriate intraoral scanner for human identification. However, as the scope of oral scanning is generally limited to teeth in the practice of dentistry, additional discussions of how to apply the IOS in forensic odontology are needed. Ultimately, the results here can contribute to the overall discussion of the forensic applicability dental data produced by intraoral scanners.