Objective:To study the morphologic standard values of craniofacial hard-tissue of the youths in Xi'an.Methods:CBCT scanned cephalometric data of 100 selected volunteers (50 males and 50 females)with individual normal occlusion were collected.31 landmarks and 31 measurements were compared between sexes and between 3D and 2D data with software InvivoDental 5.2,WinCeph 8.0.and SPSS 19.0.Results:1.In the 3D measurements,vertical growth of mandible in the females was more than that in the males. The values of torque of lower incisor,basis length,height of rumi mandibulae and length of corpora mandibulae in the males were bigger than those in the females.2.Compared with 2D measurements,there existed statistically significant differences in most parameters except U1-NA(mm).Conclusion:3D analysis with CBCT may provide more accurite morphologic data for craniofacial hard tissues.

Objective: To investigate the development rules of craniofacial development in patients with cleft lip and palate after surgical repair. Methods: 50 patients with repaired complete unilateral cleft lip and palate (UCLP) and 28 with complete unilateral cleft lip (UCL) were included. The subjects were divided into 3 groups according to their cervical vertebral maturation. Lateral cephalograms of all subjects were obtained. The data were analyzed and compared by PRISM 6. 0. Results: The values of face height (N-Me and ANSMe), mandibular size (Co-Go, Go-Gn, Co-Gn) of the patients in CS5 CS6 stage were bigger than those of the patients with the same type of cleft in CS1 and CS2 stage (P ＜ 0. 05) . The values of maxilla length and location showed no statistical difference between the development periods of the same type of cleft (P＞ 0. 05) . Conclusion: After surgical reair, with development, the maxilla of the UCLP/UCL patients may not change significantly. The mandible may grow significantly.