The influence of varying maxillary incisal edge embrasure space and interproximal contact area dimensions on perceived smile aesthetics.

Objective: The aim of this study was to determine the influence of incisal edge embrasure space and interproximal contact area dimensions on perceived smile aesthetics.
Design: Cross-sectional study.
Setting: Postgraduate dental teaching hospital.
Methods: A photograph of a smiling female, displaying only the lips and maxillary teeth was digitally altered. First, the proportions of the incisal edge embrasure spaces were modified to produce five different images. Secondly, the lengths of the interproximal contact areas were altered to produce five different images. The two sets of photographs were ranked from 'most attractive' to 'least attractive' by 35 dentists, 35 dental technicians and 35 patients.
Results: An embrasure space arrangement where the size of the embrasures increases progressively distally from the midline was deemed most attractive; absence of embrasure spaces was deemed least attractive. In assessing the interproximal contact areas, all groups assessed an arrangement where the areas between the teeth were equal (and 50% the length of the central incisor) as most attractive, and where the contact areas increased in length progressively distally from the midline as least attractive. There were few statistically significant differences between the groups in these perceptions.
Conclusion: Whilst there is broad agreement in what the participant groups deem to be aesthetic, our findings do not wholly correspond to the 'ideals' that have been previously suggested in the dental literature.