Effects of vermilion height on lip esthetics in Japanese and Korean orthodontists and orthodontic patients

Objective: To evaluate the influence of vermilion height on the assessment of lip attractiveness by Japanese and Korean orthodontists and orthodontic patients. Materials and Methods: Vermilion heights were modified by increasing or decreasing the vermilion height in 1.0-mm increments from 23.0 mm to 3.0 mm with reference to an average vermilion height. Participants ranged from 15 to 29 years of age and comprised 29 Japanese and 25 Korean orthodontists and 96 Japanese and 72 Korean orthodontic patients. They all rated the attractiveness of seven images with altered vermilion height using a visual analog scale. Results: Across the participant groups, there were significant differences in the median esthetic scores for the seven vermilion height levels tested. The Japanese and Korean raters assigned the highest scores to the average vermilion height and assigned the lowest scores to the +3-mm increased vermilion height. The ranges of vermilion height preferred by orthodontists were found to be within the ranges preferred by orthodontic patients when evaluating the preferences in lip esthetics by country. Conclusions: We conclude that the 21-mm to +1-mm range for the average vermilion height is considered attractive for lips for both Japanese and Korean people.