Esthetic preference of upper central incisor inclination in a smile profile view. A cross-sectional study

Background: The objective of this study was to determine the esthetic preference of the upper central incisor (UCI) inclination from a smiling profile view in laypeople of Latin American origin. Material and Methods: This descriptive and cross-sectional study used a smiling profile photograph that was digitally modified to generate 7 types of UCI inclinations (+15°, +10°, +5°,0°, -10°, and -15°). Thus, 160 evaluators distributed in 4 groups (40 Peruvians, 39 Mexicans, 40 Brazilians and 41 Colombians) assessed the images using a visual analog scale. Kruskal-Wallis and Dunn Bonferroni tests were applied for multiple comparisons of ratings between groups (p<0.05). Results: The general sample of evaluators of the four nationalities considered -5° the most attractive slant and 0° the second most attractive slant, although a significant difference was found in the intensity of preference (p<0.001). Further, Peruvians rated the intensity of preference being -5° (Visual analogic scale (VAS) = 80 points) and 0° (VAS = 77 points) the most attractive inclinations, Mexicans rated 0° (VAS = 90 points) and -5°, -10° and 5° (VAS = 80 points) as the most attractive, Brazilians rated the most attractive inclinations at -5° and 0° (both with VAS = 80 points) and Colombians rated the most attractive inclinations at -5°, 0°, 5° and 10° (VAS = 60 points). Conclusions: Slightly retroclined (-5°) and neutral (0°) inclinations of central incisor were the most preferred by the Latin American individuals. This result should be considered by orthodontists for treatment planning.