Factors contributing to the perception of facial asymmetry in dentists and laypersons

Abstract

The aims of this study were to find differences in how dentists and laypersons evaluate facial asymmetry and to identify factors contributing to the perception of asymmetry. Photographs of young male and female faces were transformed according to lower facial height, lower facial width, the direction of chin deviation, and the angle of chin deviation. Thirty dentists (mean age, 28.0 years; 16 males, 14 females) and 50 laypersons (mean age, 22.2 years; 24 males, 26 females) answered a questionnaire evaluating the asymmetry in 24 photographs (12 males and 12 females) using visual analog scale. The individual t-test and logistic regression analysis were used for statistical analysis. There was no difference between dentists and laypersons in evaluating photographs with a 5° chin deviation angle. Compared with laypersons, dentists evaluated photographs with 10° chin deviation angle as more asymmetric. Faces with a long lower facial height, left deviation of the chin, and a large chin deviation angle were considered to be more asymmetric than those with normal lower facial height, right deviation of the chin, and a small chin deviation angle, respectively (p<0.05). There was no consistent relationship between lower facial width and the perception of facial asymmetry in both the groups. The perception of facial asymmetry was affected by lower facial height, the direction of chin deviation, and the amount of chin deviation.