RESUMO
OBJECTIVE: This study aims to measure and analyze the lip and tooth dynamic esthetic characteristics at rest and during speech in order to provide a reference for its esthetic design and restoration among the Hani and Han populations in Yunnan Province, China. METHODS: Subjects of Hani and Han ethnicity in Yunnan were selected using multistage stratified sampling and inclusive criteria. The lip and tooth dynamic esthetic characteristics of the subjects at rest and during the pinyin pronunciation of "me", "yi", "fu", and "si" were recorded using digital photography and analyzed with computer software. RESULTS: No statistical difference was detected between the Hani and Han groups in the upper central-incisor display, when pronouncing the pinyin "yi". Furthermore, there were no statistical differences in lip dynamic esthetic parameters between the Hani and Han groups, except for the distance between the upper and lower lips when pronouncing "si". There were three kinds of correlation between the upper central-incisor edge and lower lip: separation, contact, and overlap. CONCLUSION: The display of upper central incisors and the mouth width of Hani people are larger than those of Han people when at rest. When the pinyin "si" is pronounced, the display of upper central incisors and the upper-lower lip distance of Hani people is less than that of Han people due to labial muscle movement.