Microscopic characterisation of dental fractures caused by firearm projectiles

The analysis of bone injuries resulting from high-velocity firearm projectile trauma is a complex process, due to the influence of numerous variables on the resultant injury patterns. This complexity is particularly evident in specific skeletal regions, such as the oral cavity and teeth, which have received minimal attention in forensic research. In this study, four fractured teeth from an individual interred in a mass grave dating to the Spanish Civil War (1936-1939) in Seville, Spain, were analysed to assess gunshot-related trauma.The teeth were examined using digital 3D microscopy and scanning electron microscopy (SEM). This analysis enabled the identification of features in the dental tissue indicative of perimortem trauma, including characteristics related to the fracture response of living or hydrated dental tissue. Additionally, variations in damage -such as edges, surfaces, and fracture lines- were observed, depending on the proximity of the teeth to the projectile's impact point in the oral cavity. Notably, surface damage presenting as pits was identified, with morphologies and patterns potentially linked to the forces generated by the projectile. These findings suggest that such microscopic features may serve as indicators of ballistic trauma, even in the absence of prior microscopic analyses of dental tissues.