Micro-computed tomographic evaluation of canal transportation instrumented by different kinematics rotary nickel-titanium instruments

摘要

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.