Sexual Dimorphism of the Zygomatic Bone

Abstract

This study assessed the posterior contour of left- and right-sided zygomatic bones, hypothesizing that female and male crania would exhibit different contours. The study analyzed lateral cranial views of 252 female and 318 zygomatic bones. The distance from the zygomaticofrontal suture to the jugale was calculated in addition to the length of the posterior border of the frontal process of the zygomatic bone to determine the degree of deviation from a straight line. The contour length between males and females did not differ (t=1.577(593); p=0.12) nor did the degree of deviation from a straight line (t=1.808(593); p=0.07). However, there were significant differences with regard to side (t=5.589(614); p<0.0001 and t=3.742(614); p=0.0002). Discriminant function analysis revealed no significant shape difference between sides or sexes (T2=338.7; p=0.15 and T2=244.3; p=0.94, respectively). However, canonical variate analysis demonstrated statistically significant shape differences among sexes with regard to side. The results of this study reveal morphological variation in the zygomatic bone that may differentiate sex.