Adjunctive Steps for the Removal of Hard Tissue Debris from the Anatomic Complexities of the Mesial Root Canal System of Mandibular Molars: A Micro-Computed Tomographic Study.

Introduction: This in vitro study sought to compare the efficacy of a sonic irrigant activation device with ultrasonic activation and needle irrigation in removing hard tissue debris (HTD) from anatomic complexities of the root canal system.

Methods: Twenty-seven mesial roots of extracted human mandibular molars with 2 canals connected by an isthmus were selected based on micro-computed tomography scans (12-μm voxel size). The mesial canals were mechanically prepared to ProTaper Next X3 (Dentsply Maillefer, Ballaigues, Switzerland) and anatomically distributed into 3 groups (n = 9) according to the final irrigation protocol: sonically activated irrigation (SAI) using the EDDY system (VDW GbmH, Munich, Germany) for 3 × 20 seconds, ultrasonically activated irrigation (UAI) using a size 20 Irrisafe tip (Satelec Acteon, Mérignac, France) for 3 × 20 seconds, and conventional irrigation using a 30-G needle adapted to a syringe.