Accuracy of dental identification of individuals with unrestored permanent teeth by visual comparison with radiographs of mixed dentition

Dental hygiene students' matching accuracy when comparing antemortem dental radiographs and oral photographs to simulated postmortem WinID3® odontograms

Matching dental antemortem (AM) and postmortem (PM) data for human identification is especially challenging when the workforce is limited. Dental hygienists have served mass fatality incidents (MFIs) due to dental-related expertise. However, forensics within dental hygiene education and research on transferable skills is limited. This qualitative balance design study assessed senior dental hygiene students' match accuracy of simulated cases varying in dental identifiers based on AM full mouth series (FMS) radiographs and oral photographs to PM WinID3^® odontograms to demonstrate possible disaster victim identification (DVI) transferable skills gained during formal education. A convenience sample of senior dental hygiene students (n = 31) was presented information on WinID3^® interpretation, then presented with 5 mismatched cases and asked to visually interpret each to make 10 total matches; five based on AM FMS with simulated PM WinID3^® odontograms and five based on AM photographs with PM WinID3^® odontograms. Match accuracy scores ranged from 41.9% to 58.1% for cases with 1-10 identifiers, and 77.4% to 93.5% for cases with 11-40 identifiers. Accuracy when matching AM radiographs to PM odontograms versus AM photographs to PM odontograms was compared and revealed no statistical differences in match accuracy depending on image type (p = 0.388 to 1.000). Results of this pilot study suggests transferable match accuracy skills resulted from the participants' dental hygiene formal education. These baseline skills with additional specialized training support the rationale for dental hygienists serving on DVI teams. More research is needed in education and practice when preparing dental hygienists for forensic-based service.

Automatic human identification from panoramic dental radiographs using the convolutional neural network

Human identification is an important task in mass disaster and criminal investigations. Although several automatic dental identification systems have been proposed, accurate and fast identification from panoramic dental radiographs (PDRs) remains a challenging issue. In this study, an automatic human identification system (DENT-net) was developed using the customized convolutional neural network (CNN). The DENT-net was trained on 15,369 PDRs from 6300 individuals. The PDRs were preprocessed by affine transformation and histogram equalization. The DENT-net took 128 × 128 × 7 square patches as input, including the whole PDR and six details extracted from the PDR. Using the DENT-net, the feature extraction took around 10 milliseconds per image and the running time for retrieval was 33.03 milliseconds in a 2000-individual database, promising an application on larger databases. The visualization of CNN showed that the teeth, maxilla, and mandible all contributed to human identification. The DENT-net achieved Rank-1 accuracy of 85.16% and Rank-5 accuracy of 97.74% for human identification. The present results demonstrated that human identification can be achieved from PDRs by CNN with high accuracy and speed. The present system can be used without any special equipment or knowledge to generate the candidate images. While the final decision should be made by human specialists in practice. It is expected to aid human identification in mass disaster and criminal investigation.

Comparing dental identifier charting in cone beam computed tomography scans and panoramic radiographs using INTERPOL coding for human identification

According to INTERPOL, the comparison of antemortem and postmortem dental identifiers is a scientifically reliable approach for human identification. This study aimed to quantify the prevalence of corresponding INTERPOL coded dental identifiers in cone beam computed tomography (CBCT) scans and panoramic radiographs (PR). The sample consisted of 100 CBCT scans and 100 PR taken the same day from the same patients (35 males and 65 females). Randomly and independently, forty-one INTERPOL coded dental identifiers were searched in each image. Wilcoxon test compared the prevalence of codes in CBCT scans and PR, Chi-square tested the dependence between codes and teeth; and multiple correspondence analyses (MCA) explored the association between codes and teeth in color maps for CBCT scans and PR. No statistically significant differences between the prevalence of identifiers in CBCT scans and PR were detected (p=0.693). In CBCT scans and PR, dependence between teeth and codes was detected (p<0.05). In the study sample, the strongest associations were found between the codes unerupted (UNE), partially erupted (ERU) and impacted (IMV) and third molars, both in CBCT scans and PR. INTERPOL coded dental identifiers registered on CBCT scans and PR can be exchanged during human identification.

Fashion for a reason: Oral jewellery to aid forensic odontology

Jewellery along with other personal effects have been used for human identification and acknowledged in the INTERPOL (The International Criminal Police Organization) DVI (disaster victim identification) forms. It is hypothesised that modified oral jewellery has scope as a unique personal effect that can be used in combination with other identifiers. The main aim of this study was to investigate the opinions on the use of modified tooth/oral jewellery items among 90 subjects. The secondary aim was to create and suggest an elaborated oral charting system to document oral jewellery and tooth modifications and respective abbreviations. A number of 30 dental students, 30 dentists and 30 designers/tattoo & piercing artists (groups G1, G2 and G3) responded to online closed-ended surveys (versions V1, V2 and V3). As results, G1 considered jewellery 'fashion/contemporary' (77%), unique and accepted the idea of wearing a customised oral jewellery (equally 47%). G2 considered oral jewellery as 'disgusting/vile fashion' (46.66%), unique (60%) and person' (60%). 53% accepted the idea of presenting oral jewellery to their patients. G3 associated it to 'a sign of rebellion' (53.3%), unique (40%) and accepted the idea of making customised oral jewellery (50%)Preferable designs were tooth jewel (G1), implant with Hallmark (G2) and fixed tooth ring (G3). As conclusions, oral jewellery and piercings are highly acceptable by the dental students but the uniqueness of oral jewellery was more recognized by the dentists. Modified oral jewellery has been fairly accepted among all but the preferable type of design varied. A recording of those by the dentist could potentially aid in forensic dental identifications. Therefore, an elaborated oral charting system to document oral jewellery and tooth modifications and respective abbreviations were also suggested to grant a useful reason to this fashion.