The effect of sex and age on facial shape directional asymmetry in adults: A 3D landmarks-based method study.

The DA patterns were similar in both sexes and in all age categories (a slightly bent C shape of the midline); however, some significant local differences between male age groups were found. A significantly more pronounced asymmetry compared to other age groups was found only in the youngest males from 20 to 40 years. Moreover, significant sexual dimorphism of DA rapidly decreased after middle age, likely caused by the same age-related changes of the face during aging.