Analysis of dynamic smile and upper lip curvature in young Chinese

Abstract

Research in China to classify smiles could help guide future oral reconstruction surgery in the world’s most populous country. A team led by Wen-Jie Hu of Peking University analyzed smiles from 188 young adults of Han Chinese ethnicity and categorized them according to overall shape and upper lip curvature. Consistent with studies from other populations, the researchers showed that around 60% of the participants had what’s known as a ‘commissure’ smile, typically shaped like a Cupid’s bow. Another third had a ‘cuspid’ smile, in which the lips are commonly visualized as a diamond, and the final 6% had ‘gummy’ smiles. However, unlike a previously reported Caucasian cohort, the Chinese subjects, like Koreans, had lips that tended to be straight or downward-facing, rather than curving upwards.

Keywords

Chinese Han nationality / image processing / smiles / upper lip curvature

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