Preferences for vertical position of the maxillary lateral incisors

To evaluate the preferences for vertical position of the maxillary lateral incisors among orthodontists, general dentists, and laypeople.

The study group consisted of 120 judges, 40 in each of 3 study groups. Judges were asked to give their preference for maxillary lateral incisor position while viewing an animation of an idealized smile. Perceptometrics software animated the photograph and collated responses. Each judge participated in 2 similar experiments, 1 to determine what he/she found to be the most pleasing position and another to define that position's range of acceptability. The processed data were analyzed with ANOVA (analysis of variance) and post-hoc Scheffé tests to determine mean differences among the 3 study groups.

The most pleasing protocol revealed no significant difference (P >.05) in the mean preferences of the 3 groups. The average preference was 0.6 mm above the incisal plane. No subjects chose a level incisal plane as being most pleasing. Orthodontists and general dentists had a smaller range of acceptability than laypeople. The means for lower and upper limits of acceptability for all subjects were 0.3 mm and 1.0 mm, respectively, above the incisal plane.

The judges in this study preferred that the maxillary lateral incisor to be set about 0.5 mm above the incisal plane, slightly offset from the incisal plane, and not level. The lateral incisors were best perceived when they were offset slightly from the incisal plane, and there was an acceptable range within which the lateral incisors may be placed.