Apical Extrusion of Debris in Flat-oval Root Canals after Using Different Instrumentation Systems

• The amount of apically extruded debris in teeth with flat-oval root canal systems after cleaning and shaping using the ProTaper Next, the WaveOne, the Twisted File Adaptive, or the Self-Adjusting File system was assessed.
• To our knowledge, there is no study performed using these instrumentation systems. It is known that apical extrusion of debris may impact treatment outcome and postoperative symptoms.
• We found that the Self-Adjusting File system caused more apical extrusion of debris.

IntroductionThe purpose of this study was to evaluate the amount of apically extruded debris in flat-oval root canal systems during cleaning and shaping with different instrumentation systems.MethodsSeventy-two mandibular incisors were randomly assigned to 4 groups (n = 18) according to the instrumentation system to be used: the ProTaper Next rotary system (PTN; Dentsply Tulsa Dental, Tulsa, OK), the WaveOne reciprocating system (WO, Dentsply Tulsa Dental), the Twisted File Adaptive (TFA; SybronEndo, Orange, CA) rotary/reciprocating system, and the Self-Adjusting File (SAF) system (ReDent-Nova, Ra'anana, Israel). Debris extruded during the instrumentation was collected and dried in preweighed Eppendorf tubes. Three consecutive weights were obtained for each tube, and the average was calculated. The data were analyzed using the t test and analysis of variance (Games-Howell test).ResultsThe SAF produced significantly more debris compared with the other systems (P < .05). No significant difference was noted amongst the PTN, WO, and TFA (P > .05).ConclusionsRegardless of the instrumentation system used, apical extrusion of debris was exhibited at some level, regardless of the instrumentation system used. The SAF was associated with the highest amount of debris extrusion compared with PTN, WO, and TFA.