Jin Hong, DDS,(a) Wenwei Xia, DDS,(a) Yaqin Zhu, DDS,(a) Xiaoyi Wang, DDS,(a) and Huanguo Xiong, PhD(b)
(a)Ninth People’s Hospital, Shanghai Second Medical University, and bFaculty of Mechanical Engineering, Shanghai Second Industrial University, Shanghai, P. R. China.
Purpose: To analyze the stress variations of the root canal wall of pulpless tooth by different root canal preparations (RCPs).
Materials and Methods: A finite element model was set up for the mandibular first molar with standard root shape and treated as control. Routine root canal preparation (R-RCP) and root canal preparation by step-back technique (RCP-SBT) were modeled. The study was performed under the loading at the top of the molar occlusal rest in vertical and oblique 45-degree orientations. The maximum von Mises stresses were calculated in each part of the tooth, the wall of mesial-buccal, mesial-lingual, and distal root canal.
Results: Compared with the control model, R-RCP model and RCP-SBT model showed that the maximum von Mises stress have no significant changes in each part of the tooth except in the amalgam layer, which became a little larger. There are also no larger changes on the wall of mesial-buccal, mesial-lingual, and distal root canal.
Conclusion: R-RCP and RCP-SBT will not affect greatly the root and dentin in biomechanics.
(Int Chin J Dent 2003; 3: 111-114.)
Clinical Significance: The results of the current study demonstrate that R-RCP and RCP-SBT are satisfied techniques for tooth.
Key Words: finite element analysis, root canal preparation, step-back technique.