Objective: Although various aspects of smile esthetics have been considered in many studies, few of them have compared lay people's preferences for an esthetic smile with regard to the shape of anterior teeth. The aim of this study was to evaluate the effects of the shapes of upper anterior teeth in men and women on perception of the esthetic smile by different age-sex groups of lay people.
Methods: Two pamphlets each consisting of nine smile images, which were only different in cuspids’ and incisors’ shapes, were shown to four groups of judges of different ages and sexes. They were asked to rank feminine and masculine smile images according to their preferences using a 10-cell linear horizontal visual analogue scale.
Results: Neither in men’s nor in women’s pamphlets, were there significant differences between the scores given by four groups of judges to various tooth forms. In both pamphlets, regardless of cuspid shape, all groups of judges gave significantly different scores to square, square-round and round incisors so that the median of given scores to square incisors was significantly lower than those of two other incisor forms.
Conclusions: Gender and age of lay persons did not affect their esthetic perception of the shapes of upper anterior teeth. The incisor shape was the key determinant of the observers’ esthetic preferences as the round incisors were the most esthetic. It is recommended to improve the smile esthetics by mildly rounding the mesial and distal corners of square incisors.