Determination of sex using mastoid process of dry skull in North East Region of India

Background: Identification of individuals is of utmost important during manmade disaster or natural calamities. Determination of sex is the primary priority in the process of identification. When the pelvis is not available, the skull is used for sex determination. Mastoid process of temporal bone is situated at the basolateral region of skull and is resistant to damage due to its well-protected anatomical position. Aims and Objectives: The aim of the study was to determine the sex using morphometric measurements of mastoid process in the North East Indians. The objectives were to measure length, breadth, and anteroposterior diameter of the mastoid process and to use these parameters to analyze sexual dimorphism. The application of these measurements is to determine the sex in unidentified skeleton in Forensic medicine. Materials and Methods: 72 dry human skulls (50 male and 22 female) were taken from the department of Anatomy and Forensic Medicine department of Jalpaiguri Government Medical College of West Bengal. Length, breadth, and anteroposterior diameter of mastoid process of both sides of the skulls were measured using Vernier Calliper. Results: The values of length, breadth, and anteroposterior diameter are larger in male than female. The P values for all comparisons are ≤0.004 which means that the differences are statistically significant. Here, breadth (0.234) is the most powerful discriminator in Equality test of group means. Wilk’s lambda and F values together show that mastoid breadth is a strong discriminator in determining sex along with length and anteroposterior diameter. Conclusion: Mastoid breadth has the highest discriminative power in this study. The knowledge of measurement of different parameters of mastoid process by this study will be helpful to forensic medicine and anthropology for determination of sex from unknown skull, especially in the North East India.