Influence of lip protrusion and thickness on the perception of facial profile attractiveness among subjects with different ethnic backgrounds.

Objectives: To evaluate the influence of lip protrusion and thickness on the perception of facial profile attractiveness among subjects with different ethnic backgrounds. Materials and Methods: 424 participants were divided into four groups (European, Black African, Far Eastern, and Middle Eastern) and further subdivided into two subgroups according to age (18 to 40 and 41 to 60 years). An idealized female profile silhouette image was manipulated to generate 18 images with three different lip thicknesses and six sagittal lip positions. To assess perception of facial profile attractiveness, participants completed the developed questionnaire. Results: Statistically significant differences were found among subjects with different ethnic backgrounds for all images (P < .01). Percent agreement averaged 13.89%. Within each group, scores varied with lip thickness and protrusion, with significant interaction between the two factors. Gender and age had a significant impact on profile attractiveness mean scores. Conclusions: Ricketts norms for the most favorable lip position to E-line need to be updated. Middle Eastern and Europeans regarded lips positioned + 1 mm to the norm in relation to E-line as the most attractive. Thick lips that were mildly protruded were preferred by Africans. Far Eastern participants preferred normal thickness and thin lips that were protrusive; thick lips were ranked lowest. Among the thick lips, protrusive lips were ranked higher. More personalized and culturally sensitive orthodontic treatment planning is needed to help patients achieve their desired facial esthetic outcome.