Stereophotogrammetry to reveal age-related changes of labial morphology among Chinese women aging from 20 to 60

Background The lip is of important aesthetic value and highly subjected to aging. Collecting anthropometric baseline data and understanding age-related changes of labial morphology can help with diagnosis of deformity, assessment of aging, and planning of cosmetic procedures. Many studies have focused on Caucasians, while there is a lack of anthropometric data on Chinese women. Methods A total of 169 women were enrolled in this cross-sectional study and divided into four consecutive age groups. Linear distances, angles, and surface area data were obtained via stereophotogrammetry. Intergroup comparisons between different age groups were performed to find age-related differences. Results Lip width significantly increased with age while philtrum width seemed to show no obvious change. Cutaneous upper and lower lip height increased, lengthening the lip in the vertical dimension. Decrease of upper vermilion height and changes in angles indicated that aging process shortened the upper vermilion and flattened the vermilion border. Surface area also showed age-related changes. Intergroup comparison showed no statistical significance in most variables between 20s and 30s or 30s and 40s, while age-related changes in some variables were significant between 40s and 50s. Conclusion This study provided anthropometric data of labial morphology across a wide age range. Aging process affected a variety of labial anthropometric variables. Age-related changes accelerated after 40 among Chinese women.