7Dowker SE, Elliott JC, Wonq F, et al. Determination of mineral concentration in dental enamel from X - ray attenuation measurements [ J ]. Connect Tissue Re, 1998, 38 ( 1 - 4) : 61 - 72.
8Nielsen RB, Alvassin AM. Microcomputed tomography: an advanced system for detailed endodontic research [J]. J Endod, 1995, 21(11):561 -568.
9Rhodes JS, Ford TR, Lynch JA, et al. Micro - computed tomography: a new tool for experimental endodontology [ J ]. Int Endod, 1999, 32(3): 165 - 170.
10Bramante CM, Berbert A, Borqes RP. A methodology for evaluation of root canal instrumentation [ J]. J endod, 1987, 13 (5) : 243 - 245.
