Effect of maxillary incisor labiolingual inclination and anteroposterior position on smiling profile esthetics.

Abstract Objective: To test the null hypothesis that there is no effect of maxillary incisor labiolingual inclination and anteroposterior (AP) position on smiling profile esthetics in young adult females. Materials and Methods: A facial smiling profile photograph of a Chinese woman with a normal profile, a Class I occlusion, and a Class I skeletal pattern was digitized. The digital image was modified to obtain four series comprising 29 smiling profiles. The sample of individuals rating these pictures comprised 21 orthodontic professionals and 66 undergraduates. Post hoc tests were done with the Student Newman Keuls method to analyze the data. Results: Significant differences (P < .001) were detected when each photograph's ratings were compared. The smiling profile with the highest score was the one with 5° lingual inclination, while the ones with 15° labial inclination or 4-mm retrusion had lower scores than the others. Maxillary incisor protrusion and lingual inclination were preferable compared with ret...