Morphometric Analysis of Sri Lankan Mastoid Processes and Its Application for in Gender Verification in Bioarcheology and Forensic Medicine

Objective: The present study aimed to determine sex from morphometry of the mastoid process and surface area of mastoid triangle among Sri Lankans.  
Methods: The research was conducted on 60 dry skulls collected from three locations in Sri Lanka. Eight morphometric parameters of the mastoid process were measured bilaterally and the surface area of the mastoid triangle, which is formed between the  porion, mastoidale, and asterion was calculated. Statistical analysis was performed using SPSS 23 software. An independent t-test was applied to evaluate the significance of sex-based differences for each parameter.  
Results: The findings indicated that the mean measurements were consistently larger in males compared to females for all parameters measured bilaterally. The independent t-test revealed significant sex differences in mastoid height 1, mastoid height 2, mastoid height 3, mastoid length 1, porion-mastoidale distance, and asterion-mastoidale distance. No significant differences were found for mastoid width and mastoid length 2. Mean surface area of the mastoid triangle was significantly greater in males than in females on both sides.  
Conclusion: These morphometric features of the mastoid process and mastoid triangle surface area could be effectively used for sex determination in the Sri Lankan population.