Optimal gingival display on smiling based on different facial vertical patterns in Iranians

This study aimed to determine the optimal gingival display on smiling on the basis of different facial vertical patterns in Iranians from the perspective of laypeople, maxillofacial surgeons, and orthodontists.

Photographs were obtained from short-faced, normal-faced, and long-faced males and females (1 male and 1 female from each group) aged 18-30 years. The original photographs were then modified to have 6, 4, 2, 0, -2, -4, and -6 mm gingival display. Three groups of raters (n = 40), including laypeople, orthodontists, and maxillofacial surgeons, were requested to score each photograph regarding smile attractiveness using a 5-point Likert scale. Data were analyzed using analysis of variance and the Kruskal-Wallis test.

Regarding the photographs of the normal-faced female model, all 3 rater groups gave the highest score to a 2 gingival display. In the normal-faced male model, all 3 rater groups gave the highest and lowest scores to 0 and 6 mm gingival display, respectively. In the long-faced female model, all 3 rater groups gave the same score to 0, 4, and 6 gingival display. In the long-faced male model, the 3 rater groups gave the same score to 0, 2, 4, and 6 gingival display. In the short-faced female model, all 3 rater groups gave the highest score to 0 gingival display. In the short-faced male model, the 3 rater groups gave the same score to all values of gingival display except -4 mm.

The laypeople, maxillofacial surgeons, and orthodontists all gave the highest score to the photograph of a short-faced Iranian female model with 0 gingival display.