Micro-Computed Tomographic Evaluation of Canal Transportation and Centering Ability of 4 Heat-Treated Nickel-Titanium Systems.

Introduction: This study aimed to evaluate and compare canal transportation and centering ability of 4 different root canal preparation systems produced with thermal treatments by means of micro-computed tomographic imaging.

Methods: Eighty mesial canals of human extracted mandibular molars were selected based on similar morphologic parameters and were randomly assigned to 4 experimental groups (n = 20) according to the canal instrumentation technique: HyFlex CM (HCM [Coltène-Whaledent, Allstätten, Switzerland]), HyFlex EDM (HEDM [Coltène-Whaledent]), WaveOne Gold (WOG [Dentsply Sirona, Ballaigues, Switzerland]), and OneCurve (OC [Micro-Mega, Besancon, France]). The specimens were scanned before and after root canal preparation using X-ray micro-computed tomographic imaging at a resolution of 19.