[Downs cephalometric analysis between juveniles of She and Han nationality in Lishui area of Zhejiang province].

PURPOSE: To investigate the clinical normal values of juveniles with normal occlusions of She and Han nationality in Lishui area of Zhejiang province, and compare the craniofacial characteristics between She and Han nationality. METHODS: Two hundred juveniles of She nationality and 200 juveniles of Han nationality with normal occlusion were recruited. Lateral cephalometric radiographs were taken, and Downs cephalometric analysis was performed. The data were compared using paired samples t test with SPSS 12.0 software package. RESULTS: There was no significant difference between males and females in the values of juveniles of both She and Han nationality. Compared to the male and female juveniles of Han nationality, MP-FH and U1-L1 of the She juveniles increased (P<0.05), while convexity decreased significantly (P<0.05). In addition, L1-MP of She female juveniles decreased significantly in comparison to that of Han female juveniles (P<0.05). There was no significant difference in other values between She and Han nationality. CONCLUSIONS: Compared to Han juveniles, She juveniles present an orthognathous and long face with vertical growth pattern. Sex differences are not apparent in juveniles of both She and Han nationality.