Does facial growth pattern affect the perception of lower facial asymmetry?

To investigate the influence of vertical facial type on esthetic perception of lower facial asymmetry as evaluated by orthodontists, dentists, and laypeople.

Three adult females were selected with normal growth patterns (NGP), vertical growth patterns (VGP), and horizontal growth patterns (HGP). Frontal photographs were made symmetric and digitally altered, rotating the lower facial third clockwise, ranging from 0° to 6° in 1° increments. A web-based survey was designed with 24 images (eight images for each model) in random order. Each image was rated using a scale ranging from 0 (unattractive) to 10 (the most attractive) by 75 orthodontists, 73 dentists, and 78 laypeople. Kruskal-Wallis test was used to determine whether differences among groups were significant. Pairwise comparisons were made with Mann-Whitney U test. The significance level was set at P = .05.

In NGP, orthodontists and dentists could recognize slighter deviations (2°), while deviations in VGP and HGP under 3° were not recognized by all groups. Severe deviations (≥4°) were distinguished better in HGP by orthodontists and laypeople. In VGP and NGP, there was no significant difference over 4°.

Growth pattern has a significant influence on perception of lower facial asymmetry. Less severe asymmetry can be detected better in NGP. In severe degrees, increments of asymmetry can be perceived more in HGP by orthodontists and laypeople.