Related Experiment Video
Updated: Jun 14, 2026

Scanning Electron Microscopic Evaluation of Surface Defects of Remover Retreatment File After Single and Multiple Uses
Published on: October 11, 2024
Micro-computed tomographic comparison of nickel-titanium rotary versus traditional instruments in C-shaped root canal
Xingzhe Yin1, Gary Shun-Pan Cheung, Chengfei Zhang
1Department of Special Dentistry, Peking University School and Hospital of Stomatology, Beijing, China.
Introduction:
The purpose of this study was to assess the efficacy of instrumentation of C-shaped canals with ProTaper rotary system and traditional instruments by using micro-computed tomography (micro-CT).
Methods:
Twenty-four mandibular molars with C-shaped canals were selected in pairs and sorted equally into 2 groups, which were assigned for instrumentation by ProTaper rotary system (ProTaper group) or by K-files and Gates-Glidden burs (Hand Instrument group). Three-dimensional images were constructed by micro-CT. The volume of dentin removed, uninstrumented canal area, time taken for instrumentation, and iatrogenic error of instrumentation were investigated.
Results:
Hand Instrument group showed greater amount of volumetric dentin removal and left less uninstrumented canal area than ProTaper group (P < .01). The time needed for instrumentation was shorter for ProTaper group than for Hand Instrument group (P < .05). No instrument breakage occurred in both groups, but more conspicuous procedural errors were detected in Hand Instrument group than for ProTaper group.
Conclusions:
It was concluded that ProTaper rotary system maintained the canal curvature with speediness and few procedural errors, whereas traditional instrumentation can clean more canal surface.
