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Scanning Electron Microscopic Evaluation of Surface Defects of Remover Retreatment File After Single and Multiple Uses
Published on: October 11, 2024
Effects of two nickel-titanium instrument systems, Mtwo versus ProTaper universal, on root canal geometry assessed by
Guobin Yang1, Guohua Yuan, Xiaofei Yun
1Key Laboratory for Oral Biomedical Engineering of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China. Guobin.yang@163.com
Introduction:
The aim of this study was to compare the effects of Mtwo and ProTaper Universal (PTU) on root canal geometry three-dimensionally by using micro-computed tomography.
Methods:
A total of 20 canals were prepared with Mtwo or PTU system. Micro-computed tomography scanner was used to scan the specimens before and after instrumentation. Three-dimensional images were reconstructed. The parameters evaluated included canal surface area, volume, structure model index, thickness, straightening, canal transportation, and uninstrumented surface area.
Results:
Preparation significantly changed canal surface area, volume, structure model index, thickness, and canal curvature. There were no significant differences between instrument types concerning these parameters and uninstrumented surface area. The canals prepared with PTU showed larger values of transportation compared with those in Mtwo group at the apical third.
Conclusions:
Both of the instrumentation systems produced canal preparations with adequate geometry. PTU produced larger transportation at apical third.