Evaluation of the amount of debris from the apikal during the preparation of the root canal using different rotary file systems

Objective: The purpose of this in vitro study was to evaluate working time and the weight of debris extruded apically from canal shaping of single-rooted human mandible premolar teeth using different Ni-Ti rotating file systems. Method: In this study, 60 pieces of single-rooted human mandible premolar teeth were used. When choosing the teeth, the root growth was completed, the root end closed, single rooted and flat canals were preferred. The teeth were randomly divided into four groups (n=15). Root canals were produced using ProTaper Gold, HyFlex EDM, iRace file systems and hand files according to the manufacturer's instructions. The apically extruded debris was collected in preweighted Eppendorf tubes with an analytical balance. The Eppendorf tubes were then stored in an incubator at 70 °C for 5 days in order to evaporate the distilled water before weighing the dry debris. The amount of extruded debris was assessed with an analytical balance. To determine the total time for root canal preparation was recorded using a digital chronometer. The amount of extruded debris were analyzed statistically using Kruskal Wallis test and Dunn-Bonferroni correction method used for multiwise comparison. The working times were analyzed statistically using one-way ANOVA and post-hoc Dunnett's T3 tests at a significance level of P < 0.05. Results: The results show that the least apically axtruded debris associated with iRace among all other groups (P<0.05). Instrumentation performance was significantly better using iRace and HyFlex EDM groups than with all other instruments (p<0.05). Conclusion: In this study, it was determined that regardless of the instrumentation system used, apical extrusion of debris was induced at some level. Consequently, iRace was associated with the least amount of debris extrusion and more advantageous working time compared with all other instruments which used. Keywords: Root canal preparation, Ni-Ti instrumentation, apically extruded debris