68 страниц. 2013 год. LAP Lambert Academic Publishing The objective of this study was to define age-related changes in the human smile. The areas of interest were: upper lip length at smile and repose, upper lip thickness at smile and repose, maxillary incisal display at smile, interlabial gap height at smile,smile index, percent buccal corridors, intercommissural width at rest, smile height, and smile arc.Video equipment was used to capture video for 150 subjects. Two frames for each subject were selected; one frame representing the lips at rest and the second representing the widest smile. After excluding 50 subjects the data for the remaining 100 subjects was analyzed with equal number of males and females.This study helps to establish age related dynamic changes. As the person ages the smile gets narrower vertically and wider transversely. The dynamic measures indicate that the muscles' ability to create a smile decreases with increasing age.