Tomographic-cephalometric evaluation of the pars petrosa of temporal bone as sexing method

Abstract

This study assesses a common issue in Forensic Anthropology: sex determination in fragmented or incomplete human skeletal remains. Previous studies have reported a significant sexual dimorphism in adult individuals for the lateral angle and acoustic pore of the pars petrosa of temporal bone. Our aim is to test the usefulness of pars petrosa as method for estimating sex using standardized CT axial images and cephalometric techniques. We evaluate four cephalometric markers of the pars petrosa (lateral angle, acoustic pore diameter, the divergence of the medial-posterior and medial-anterior segments, and a proposed angle named “Cephalometric Angle of pars petrosa”) in 150 adult individuals of known sex and age treated in the Hospital Beneficência Portuguesa (São Paulo, Brazil). Discriminant analysis using these four parameters allows correct sex classification in 72 % of individuals, however, the Cephalometric Angle, individually, reaches 74 % of correct classifications. Our results suggest that tomographic-cephalometric evaluation of the pars petrosa of temporal bone can be employed as indicial method for differentiating sex in some contexts.

Keywords

• Lateral angle
• Forensic anthropology
• Internal acoustic canal
• Sexual dimorphism
• Human identification