Differences Among Deviations, Genders, and Observers in the Perception of Eye and Nose Asymmetry.

This study investigated the degree and range of recognition of canting of the interpupillary line and deviation of the nose, which were regarded as "normal," "acceptable," and "needing surgical correction," according to different observer groups.Four different groups (40 each for laypeople, dental students, general dentists, and orthodontists) rated 11 simulated asymmetric images with canted eyes and a deviated nose separately. The raters categorized each image as normal, socially "acceptable" and not requiring correction, or abnormal and would benefit from correction. Survival analysis was used to evaluate the scope of perception.The degree of recognition for eye-canting and nose deviation was 2.31 and 2.92, respectively. Eye-canting and nose deviation had lower degrees of recognition in the clockwise direction (2.13°) and on the left side (2.65°), respectively. Women showed a lower degree of the "upper limit of the acceptable range" for canted eyes, and men showed a lower "degree of recognition" and "upper limit of the acceptable range" for a deviated nose. Orthodontists showed a larger upper limit of the acceptable range for eye-canting (P < .001).The perceptions of asymmetry of canted eyes and deviated nose were affected by gender, direction of asymmetry, and observer groups.