Effect of the interproximal contact level on the perception of smile esthetics

Many dental and facial components affect smile esthetics, and dental professionals' opinions regarding dental esthetics may not always coincide with the perceptions and expectations of the patients.

This work is designed to determine the dimensions of the interproximal contact areas that are considered the most or least attractive according to a group of laypersons, dentists and technicians.

Two photographs of female and male smiles showing a full smile were taken with a Nikon® camera and digitally altered using Adobe® Photoshop. The length of the interproximal contact areas was altered to generate 2 sets of images (3 images of the female and 3 images of the male smile in each set). A group of 40 laypersons, 40 dentists and 40 dental technicians were asked to select the most and the least attractive image in each set.

An interproximal contact ratio of 50:40:30 [%] was the most attractive arrangement (40.00% and 38.33% for the female and male smiles, respectively). The 'reversed' ratio of 30:40:50 [%] was the least attractive to the participants (57.50% and 44.17% for the female and male smiles, respectively). There were differences in the rankings of the most and the least attractive smiles among the 3 groups of evaluators.

The 'ideal' interproximal contact ratio of 50:40:30 [%] is perceived to be the most attractive. However, the smile esthetics perception among dental professionals is not always in agreement with the perception of laypersons.