Factors Affecting Smile Attractiveness: An Eye Tracking Study

Objective: The purpose of this study was to evaluate the effects of the buccal corridor width, gingival display, and upper midline deviation on smile aesthetics. Methods: A frontal posed smile photograph (reference photograph) of a young female was rearranged using digital imaging software to produce artificially created photographs that exhibited different buccal corridor widths, midline deviations, and gingival displays. A total of 21 images were obtained with reference photograph. While an eye tracking device was recording, each image was evaluated and assigned aesthetic scores by 16 laypeople (8 males, 8 female). A total of 336 laypeople participated in the study. A 5-point Likert scale was used for scoring. One-way ANOVA, Welch's T-test, Tukey’s HSD test, and Tamhane's T2 test were used for statistical analysis. P values of less than 0.05 were considered statistically significant. Results: The highest and lowest scores were assigned to 2- and 8-mm buccal corridor widths, respectively. Gingival displays of +2 and above, and +5 mm and above were scored significantly lower than the reference image (p<0.05) by female and male participants, respectively. There was a significant difference in 6-mm gingival display for males (p<0.05). Conclusions: The different buccal corridor widths yielded no significant difference in attractiveness scores or focusing times for either gender. In the midline evaluation, even a deviation of 6 mm was not noticed by laypeople and was not found to be less attractive.