Review of a forensic pseudoscience: Identification of criminals from bitemark patterns

Forensic odontology and dental age estimation research: a scoping review a decade after the NAS report on strengthening forensic science

Dental age estimation (DAE) is one of the most reliable and useful scientific methods employed by forensic odontology (FO) for human identification. In 2009, the US National Academy of Sciences (NAS) report highlighted the need to deepen research in many disciplines, among which FO received strong criticism for specific expertise. The aim of this review is to provide a comprehensive overview in order to systematically map the latest original research done in FO, as well as identify DAE within this field. A systematic search was performed from 2014 to 2019. In total, 644 studies were identified for qualitative analysis: DAE was the most studied topic (41.30%). Asia was the most productive continent with 58.27% of the global production on DAE; India was the most productive Asian country, with 32.33% and 55.48% of global and Asian production, respectively. The University of Macerata (Italy), KU Leuven (Belgium), University of Split (Croatia), and University of São Paulo (Brazil) led DAE research. Authors from leading countries on DAE research demonstrated great individual productivity, which is evidence of their scientific efforts, but also possible risks if the continuity of this line of research depends on them. Although FO has significantly focused its research on DAE, the absence of publications on controversial topics but necessary for research according to the NAS report shows the possible lack of interest of authors or journals to address them.

Exploring the degrees of distortion in simulated human bite marks

The properties of the skin and the posture of the body during photographic recording are factors that cause distortion in the bite mark injury. This study aimed to explore the degree of distortion between a ‘touch mark’ (method 1) and a ‘bite mark’ (method 2) on the left upper arm at three different positions (arm relaxed; arm flexed in two different positions). A pair of dental casts with biting edges coated in ink was used to create a mark in 30 subjects (6 ♂, 24 ♀) aged 20–50 years old. Photographs were taken using a Nikon DX digital camera (D5000). The mesiodistal widths and angle of rotations of both upper right central incisor and lower right central incisor and the inter-canine distances were analysed and compared with the true measurements using Adobe Photoshop CC 2017. Statistical analysis was carried out using SPSS Statistics 22 applying a 2 (mark type) × 3 (position) repeated measures ANOVA. For all measures studied, there was a statistically significant difference between mark types and positions. In the case of bite marks, a great degree of distortion was detected, and this increased further when changing the position of the arm. The findings demonstrated that skin properties and posture influence distortion. This could lead to inaccurate measurements and misleading pattern interpretation of bite mark injuries.