Comparison of objective and subjective assessments for perception of facial symmetry

Abstract

Objectives: Symmetrical patterns of the face are generally preferred by the viewers. However, the process of perception of symmetry is far from perfect and is affected by subjective factors. In this study, we aimed to demonstrate the differences between objective and subjective assessments for perception of facial asymmetry. Methods: For objective evaluation, the anteroposterior photographs of 450 volunteers were analyzed anthropometrically for symmetry. Subjective evaluations were conducted by seven individuals who assessed each face based solely on symmetry. Results: We found a difference between objective measurements and subjective evaluations. No statistically significant difference concerning the rates derived from anthropometric points was found between sexes. After the comparison of these rates, no subject was found to have a perfectly symmetrical face, and all subjects showed some asymmetry in one or more of their anthropometric points. Conclusion: With subjective evaluation, asymmetry was found most commonly in the middle third of the face. Nose and alar margins may be the determining points for the observer during subjective evaluation, thus we think the best region to infer asymmetry from is the middle third of the face. Because of this, thousands of patients complain of asymmetrical noses and undergo rhinoplastic surgery every year. This study also demonstrates individual differences in subjective evaluations. These differences and lack of objectively symmetrical faces for every set of points are very important for patients requesting plastic surgery procedures asuch as rhinoplasty out of aesthetic concerns. Keywords: facial asymmetry; objective assessment; subjective assessment