Buccal corridors and smile esthetics

Purpose: The purpose of this study was to determine the influence of buccal corridors on smile attractiveness when judged by lay persons. Material: Full-face color slides of 10 randomly selected smiling subjects (5 women, 5 men) were digitized. The maxillary posterior dentitions for all subjects were digitally altered to produce a range of smile fullness: narrow (28% buccal corridor), medium-narrow (22% buccal corridor), medium (15% buccal corridor), medium-broad (10% buccal corridor), and broad (2% buccal corridor). The 5 images of each subject were paired into 11 possible combinations, and the resulting 110 pairings were randomly projected to a panel of 30 adult lay persons who compared the 2 images in each pair for smile attractiveness. Results: Statistical analysis with the Wilcoxon signed-rank and rank-sum tests showed that (1) a broader smile (minimal buccal corridor) was judged by lay persons to be more attractive than a narrow smile (larger buccal corridors), and (2) no significant differences were found in judging between male and female subjects or between male and female judges. Conclusions: Having minimal buccal corridors is a preferred esthetic feature in both men and women, and large buccal corridors should be included in the problem list during orthodontic diagnosis and treatment planning.