Laypersons' perception of facial and dental asymmetries.

The purpose of this article was to determine the individual visual perception thresholds of certain facial and dental discrepancies for a symmetric face model (SFM). A facial photograph of a female subject's smile was digitally manipulated into an artificially symmetric picture. Modifications were made on the SFM for shifts in the dental midline, nose, and chin (group 1) and cants of dental midline and incisal plane (group 2), resulting in a total of 24 different images divided into two groups. One-hundred randomly selected laypersons divided into two groups were used to evaluate each image according to their own personal beauty and esthetic criteria using a visual analog scale. The visual perception thresholds found for the SFM were 2 mm for a dental midline shift, 4 mm for nose deviation, 5 degrees for dental midline cant, and 3 degrees for frontal incisal plane cant. Chin deviations of 6 mm or less were not noticed. Dental midline shift, nose deviation, dental midline cant, and incisal plane cant relative to an SFM have an impact on the perception of facial attractiveness. Chin deviations did not have a statistically significant impact.