The Impact of Occlusal Plane Cant Along with Gingival Display on Smile Attractiveness

Abstract

Structured Abstract

ObjectivesTo evaluate the influence of occlusal plane cant in conjunction with maxillary gingival display on perception of smile attractiveness by orthodontists, dentists, and laypersons.

Setting and sample populationFaculty of Dentistry at Baskent University. A total of 204 raters for smile attractiveness.

Materials and methodsA frontal intra-oral photograph of aligned teeth was modified using image processing software. Six different occlusal lines representing 0 degrees to 5 degrees cants were obtained by tilting the photographs. Each occlusal cant was adjusted in five manners resulting in five different gingival display amounts. Attractiveness of the 30 different smiles was evaluated by 204 raters divided into three groups (n = 68 in each group).

ResultsBoth occlusal cant (p < 0.001) and gingival display amount (p < 0.001) had a statistically significant influence on smile attractiveness. Smile attractiveness scores with reference to amount of gingival display showed a significant difference between rater groups (p < 0.001). Orthodontists preferred 1-mm coverage of upper central incisors by the upper lip, whereas dentists and laypersons preferred 2 mm. Significant (p < 0.001) interaction was observed between occlusal cant and gingival display amount, which influenced smile attractiveness.

ConclusionIncrease in both occlusal plane cant and gingival display negatively influences smile attractiveness. The influence of occlusal plane cant becomes less when gingival display increases, whereas the influence of gingival display decreases when occlusal cant increases. Dentists are more generous than orthodontists, while laypersons are the most generous regarding smile attractiveness scores.