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Updated: Apr 26, 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 evaluation of canal transportation instrumented by different kinematics rotary
Richard Gergi1, Reza Arbab-Chirani2, Nada Osta1
1Faculty of Dentistry, Department of Endodontics, Saint-Joseph University, Beirut, Lebanon.
Introduction:
The purpose of this study was to evaluate and compare canal transportation of curved root canals by using 3 nickel-titanium systems: Reciproc, WaveOne, and Twisted Files Adaptive (TF).
Methods:
Twenty-four extracted human mandibular molars with 2 separate mesial canals and severe angle of curvature were selected. Individual canals were divided randomly to 1 of the 3 experimental groups: Reciproc group, reciprocating instrumentation with Reciproc R25; WaveOne group, reciprocating instrumentation with the Primary WaveOne file; and TF Adaptive group, Adaptive Rotary Motion with the TF files. Each group consisted of 16 root canals. Specimens were scanned before and after root canal preparation with an isotropic resolution of 20 μm by using micro-computed tomography. The degree of canal transportation, in addition to instruments' centering ability, was recorded.
Results:
Less transportation occurred with TF Adaptive rotary instruments (P < .0001). The mean degree of canal transportation in the apical third was significantly lower with TF Adaptive group (P < .0001). No significant difference was found between Reciproc and WaveOne systems (P = 1.000). Mean centering ratio was the highest statistically with TF Adaptive (P < .0001), followed by WaveOne, and was minimal with Reciproc (P < .05).
Conclusions:
The TF Adaptive system was found to have less canal transportation and better centering ability when compared with the reciprocating groups.

