Point taken: An unusual case of incisor agenesis and mandibular trauma in Early Bronze Age Siberia

This paper focuses on the mandible of an adult male individual (radiocarbon dated to 4420-3995cal BP) from the Early Bronze Age Cis-Baikal cemetery of Ust'-Ida I (Siberia, Russian Federation). The mandible contains two features of interest: (1) bilaterally missing central incisors, and (2) the tip of a lithic projectile point embedded in the symphyseal region. Despite the absent teeth, the mandible presents a dental arcade without diastemata, appearing normal and complete on first glance. Three different levels of CT (computed tomography) imaging-ranging from clinical to synchrotron-based-were employed in order to establish the aetiology behind the missing dentition, whether subsequent to the projectile trauma or entirely unrelated to it. Results indicate that the mandible exhibits two highly unusual but unrelated features: probable bilateral agenesis of the central incisors and perimortem trauma to the mental symphysis. In addition, the embedded tip was successfully matched via digital imaging to photographs of a broken projectile point, an artefact recovered from the facial region of the skeleton.