[Preliminary study on analysis method of spontaneous smile and application].
OBJECTIVE
To investigate the smile esthetic elements of Chinese Han-nationality female based on high definition (HD) digital camera with computer-image measuring technique.


METHODS
HD digital camera was used to capture spontaneous smile process combined with computer-image measuring technique to establish the analysis method of smile. Ninety-nine Han-nationality female with normal gingiva, aged from 20 to 30 years were recruited. The lip-incisor edge distance, gingival display were measured. The data was statistically analyzed.


RESULTS
A standard and objective method to analyze spontaneous smile was established. Forty-three percent (43/99) of the subjects studied were classified as having a high smile and average smile respectively, 13% (13/99) as having a low smile. Gingival display accounted for (1.34 ± 0.98) mm in high smile type.


CONCLUSIONS
Average smile and high smile type were most common in the Chinese Han-nationality female studied.
Department of Periodontology, Peking University School and Hospital of Stomatology, Beijing 100081, China.
Yan-ling
YL
Zhang
Hao
H
Zhang
Wen-jie
WJ
Hu
Zhan-qiang
ZQ
Cao
D000328:Adult; D000704:Analysis of Variance; D044466:Asian People; D002508:Cephalometry / Q000379:methods; D004955:Esthetics, Dental; D005260:Female; D005881:Gingiva / Q000033:anatomy & histology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007180:Incisor / Q000033:anatomy & histology; D008046:Lip / Q000033:anatomy & histology; D012904:Smiling; D055815:Young Adult