It is well known that the head and face are smaller in females than in males. However, almost all previous studies have quantified the size difference between males and females as simple numerical values, which might not clarify the difference. The pr...
It is well known that the head and face are smaller in females than in males. However, almost all previous studies have quantified the size difference between males and females as simple numerical values, which might not clarify the difference. The present study evaluated the female-to-male proportions of the head and face so as to clarify the sex-related differences. Totals of 1939 females and 1398 males were divided into three age groups: young (20-39 years), middle-aged (40-59 years), and elderly (60-79 years). The dimensions were classified into three categories: five cephalic, three frontal facial, and six lateral facial. Cephalic and frontal facial dimensions were measured directly on the head and face, and lateral facial dimensions were measured indirectly on standardized photographs. The female-to-male proportions of individual dimensions were compared in the three age groups using the following formula: female measurement value × 100 / (mean of male measurement value).
The female-to-male proportions of the cephalic dimension increased with age, with the female cephalic dimensions overall being about 96% of the male cephalic dimensions. The female-to-male proportions of the frontal facial dimension were constant across the age groups, with the female frontal facial dimensions overall being 95% of the male frontal facial dimensions. The female lateral facial dimension increased markedly from the young to middle-aged group, and was constant or decreased slightly from the middle-aged to elderly group. Overall the female lateral facial dimensions were about 97% of the male lateral facial dimensions. The presence of cephalic and facial dimensions that were greater in females than in males varied with the measured dimension. Overall 14.8%, 16.1%, and 38.6% of cephalic, frontal facial, and lateral facial dimensions, respectively, were greater in females than in males.