Automatic removal of soft tissue from 3D dental photo scans; an important step in automating future forensic odontology identification.

The potential of intraoral 3D photo scans in forensic odontology identification remains largely unexplored, even though the high degree of detail could allow automated comparison of ante mortem and post mortem dentitions. Differences in soft tissue conditions between ante- and post mortem intraoral 3D photo scans may cause ambiguous variation, burdening the potential automation of the matching process and underlining the need for limiting inclusion of soft tissue in dental comparison. The soft tissue removal must be able to handle dental arches with missing teeth, and intraoral 3D photo scans not originating from plaster models. To address these challenges, we have developed the grid-cutting method. The method is customisable, allowing fine-grained analysis using a small grid size and adaptation of how much of the soft tissues are excluded from the cropped dental scan. When tested on 66 dental scans, the grid-cutting method was able to limit the amount of soft tissue without removing any teeth in 63/66 dental scans. The remaining 3 dental scans had partly erupted third molars (wisdom teeth) which were removed by the grid-cutting method. Overall, the grid-cutting method represents an important step towards automating the matching process in forensic odontology identification using intraoral 3D photo scans.

Skin lesions in 397 children referred for forensic medical examination on suspicion of physical abuse.

INTRODUCTION: Physical child abuse is a well-known global health problem. Considerable efforts have been devoted to identifying predictors of physical abuse. METHODS: This study included all 397 cases in the cohort of children aged 0-18 years referred to the Department of Forensic Medicine, Aarhus University, Denmark, between 2000 and 2020 on suspicion of exposure to physical abuse. The number, character and location of skin lesions were described. Bone fractures were recorded. A total of 59 cases involving weapons and sharp force violence related to attack or fighting between young people were assessed as a separate group. RESULTS: The annual number of cases referred increased. The male-to-female ratio in the cohort was 6:4. Bruising was the most common skin manifestation in the blunt force violence (BFV) group; 72.2% of the individuals had skin lesions on the head and neck, thus visible on a normally dressed child. Lesions on the hands and arms were present in 69.8% of the BFV cases and may partially reflect defensive reactions. One or more bone fractures were recorded in 19.5% of the BFV group. Occult fractures were observed in 40% of the children in the BFV group ≤ 2 years of age. CONCLUSIONS: More than 70% of the children in the BFV group had lesions on the head and neck visible on a normally dressed child. Skin lesions on hands and arms, which are visible on a lightly dressed child, were just as frequent. Persons with close relation to children should be aware of this opportunity to spot non-accidental skin injuries. FUNDING: none. TRAIL REGISTRATION: not relevant.

Odontological identification dental charts based upon postmortem computed tomography compared to dental charts based upon postmortem clinical examinations.

Since the beginning of this century, the use of postmortem computed tomography (PMCT) in forensic autopsies has increased. In this study we examined how similar dental charts created using PMCT as a solitary examination mode were to dental charts created using the conventional method of a clinical inspection including intraoral radiographs. A total of 100 previously performed dental identification cases were retrospectively included in the study. For each case, a dental chart was created solely based upon PMCT. The PMCT based dental chart was subsequently compared with the chart created from the previous conventional identification examination. Based upon the accuracy, sensitivity and specificity values PMCT performed very well compared to the conventional method in the identification concerning presence or absence of teeth, the presence of crowns, bridges and endodontic treatments as well as the presence and types of fillings. PMCT performed poorly concerning the extension of fillings and identification of small, tooth-colored fillings. The use of PMCT is a valuable supplement to the conventional methods available for forensic odontologists and may be of great value for initial screening in mass fatalities.