4Kawamata A,Fujishita M.Panoramic three dimensional XCT imaging.Dent Rodiol,1998,(3):193.
5Checchi L,Bonetti GA,Pelliccioni GA,et al.Removing highrisk impacted mandibular third molar:A surgical-orthodontic approach.J Am Dent Assoc,1996,127(8):1214.
6Freisfeld M, Dahl IA,Jagar A, et al. X-ray diagnosis of impacted upper canines in panoramic radiographs and computed tomography[J]. J Orofac Orthop, 1999,60 (3): 17-184.
7Freisfeld M, Dahl IA, Jager A, et al. X-ray diagnosis of impacted upper canines in panoramic mdiographs and computed tomographs[J].J Orofac Orthop, 1999,60(3): 177-184.