Subjective and objective evaluation of frontal smile esthetics in patients with facial asymmetry-a comparative cross-sectional study.

Abstract

To analyze the relationship between subjective and objective evaluations of pre-treatment posed smiles in patients with facial asymmetry and to assess the influence of dentofacial structures involved in asymmetry on the perception of smile attractiveness. Thirty-five patients (25 males and 10 females) between 18 and 25 years of age with facial asymmetry were selected. Pre-treatment clinical photographs of posed smiles were subjectively evaluated by a panel of 20 orthodontists, 20 oral surgeons, and 20 laypersons. A customized Smile Mesh program was used for objective evaluation of the same smiles. Direct comparison among three smile groups (unattractive, slightly attractive, and attractive) for different Smile Mesh measurements was carried out using two-way anova test. Additionally, linear regression was performed to evaluate whether these measurements could predict the attractiveness of captured smiles. Patients with 'slightly attractive' smiles had a significantly greater distance between the incisal margin of the maxillary central incisor and the lower lip during smiling. The Smile Index was significantly greater in attractive smiles. However, based on the coefficients of linear regression, no objectively gathered measurement could predict smile attractiveness. Attractiveness or unattractiveness of smiles in patients with facial asymmetry could not be predicted by any measurement of Smile Mesh. The presence of facial asymmetry did not significantly influence the perception of smile esthetics.