5Zhang R, Wang H, Tian YY, et al. Use of cone-beam com- puted tomography to evaluate root and canal morphology of mandibular molars in Chinese individuals[J]. Int Endod J, 2011, 44(11):990-999.
6La SH, Jung DH, Kim EC, et al. Identification of indepen- dent middle mesial canal in mandibular first molar using cone-beam computed tomography imaging[J]. J Endod, 2010, 36(3):542-545.
7Mouyen F, Benz C, Sonnabend E, et al. Presentation and physical evaluation of Radio Visio Graphy[J]. Oral Surg Oral Med Oral Pathol, 1989, 68(2):238-242.
8Versteeg CH, Sanderink GC, van der Stelt PF. Efficacy of digital intra-oral radiography in clinical dentistry[J]. J Dent, 1997, 25(3/4):215-224.
9Hess W, Zurcher E. The anatomy of the root canals of the teeth of the permanent and deciduous dentitions[M]. New York: New York Willion Wood, 1925:1-39.
10Barker BC, Lockett BC, Parsons KC. The demonstration of root canal anatomy[J]. Aust Dent J, 1969, 14(1):37-41.
