Validity of Metric Assessment of Mastoid Triangle in Sex Determination: An Anatomical Study

Objective: This study aimed to evaluate the validity of the mastoid triangle anthropometric measurements and area between the three craniometric points, namely porion (po), asterion (ast), and mastoidale (ms) as a sex determinant. Materials and Methods: A total of 60 dry skulls (30 males and 30 females) were assessed for 10 morphometric measurements with a compass, and a total of 120 mastoid triangles were evaluated. Results: Statistically significant differences were found in all the mastoid triangle measurements between males and females (p=0.01). Discriminant function analyses revealed that the left po-ms length and the total area of the mastoid triangle were two variables with the highest sensitivity at an accuracy rate of 90%. The models with three mastoid triangle variables including the total po-ms, total ms-ast, and total po-ast measurements, in combination, provided high discriminant potentials of 96.7% and 93.3% in females and males, respectively. When the total po-ms, total ms-ast, and total po-ast were used together, a greater sexual dimorphism was observed, correctly classifying the sex with a 95% accuracy rate. The mean value of the total area which is preferred due to the asymmetry between the sides of the skull was 1455.2 mm(2) in males and 1341.2 mm(2) in females. Conclusion: In the light of the obtained results, the discriminant function analyses of the mastoid triangle measurements are concluded to be reliable in sex determination and preferable in forensic medicine and anthropology.