Using 3D images of Korean's mastoid process to estimate sex: A metric study

This study reports an approach for forensic anthropological sex estimation by examining the mastoid process in Koreans using three-dimensionally reconstructed computed tomography images of skulls. The purpose was to validate this metric sex estimation method using only the mastoid process in a Korean population compared to a non-metric sex estimation method derived from a previously used non-Korean method. In this study, 661 images were gathered and 100 of these were randomly set aside for use in the non-metric method. We then applied our metric analysis to the remaining 561 images. Our findings showed that the volume of the mastoid process in males was greater than that in females. As a result, using the mastoid process volume in a metric method increased the accuracy of sex estimation by 20% compared to that using the non-metric method. Our metric methods for sex estimation are more applicable to skulls found in Korea than to those from non-Korean populations, and the metric methods for sex estimation are more useful than non-metric methods. In future studies, it is necessary to derive new equations from measurements of the glabella, mental eminence, supraorbital margin, and nuchal crest for Korean skulls; this method contributes to increased accuracy and reliability of sex estimation using Korean skulls.