Cephalometric determinants of facial attractiveness: A quadratic correlation study.

Introduction: This research aimed to determine the nonlinear correlation between lateral cephalometric measurements and facial attractiveness, evaluated in the frontal and profile views. A quadratic correlation was studied, in which the vertex of the function indicates the cephalometric value corresponding to the maximum attractiveness.

Methods: Frontal and profile facial attractiveness of 60 patients with Class I (n = 20), Class II (n = 20), or Class III malocclusion (n = 20) aged 18-35 years without previous orthodontic treatment was evaluated by 14 laypersons (7 men and 7 women) with a visual analog scale. Soft- and hard-tissue measurements were collected on lateral cephalometric radiographs. Pearson and nonlinear quadratic correlations between the attractiveness of the face and cephalometric measurements were calculated. Maximum attractiveness values (MxAt) were determined for the significant cephalometric variables.

Results: Significant quadratic correlations were found between frontal facial attractiveness and the following variables: Ls-SnPog' (r = 0.45; MxAt = 3.1 mm), Li-SnPog' (r = 0.41; MxAt = 3.8 mm), the ANB angle (r = 0.42; MxAt = 0.2°) and MPA (r = 0.51; MxAt = 31.9°). Profile attractiveness correlated nonlinearly with Ls-SnPog' (r = 0.42; MxAt = 3.2 mm), Li-SnPog' (r = 0.41; MxAt = 3.9 mm) and MPA (r = 0.46; MxAt = 32.4°).

Conclusions: Significant quadratic correlations were found between facial attractiveness and cephalometric measurements, which were stronger than linear correlations. The maximum attractiveness points indicated a tendency for laypeople to consider a more protrusive lower lip and an ANB angle lower than the norm as the most attractive.