Change in facial shape in two cohorts of Japanese adult female students twenty years apart

Introduction: Secular changes in the head and body dimensions of the Japanese population were recorded during the last century, but studies on Japanese adult facial shape were poorly documented. This study aimed to document the secular changes in facial shape and their association with craniofacial measures of Japanese adult female students. Methods: Data were collected from 1998–2001 and 1975–1979 from institutions in Tokyo and Kyoto. The prosopic index (PI) was derived from morphological facial height (n-gn) and bizygomatic breadth (zy-zy). Multiple regression analysis was used to determine