Evaluation of debris extrusion using passive ultrasonic irrigation associated with different endodontic irrigants

The objective of this study was to evaluate the amount of extruded debris after chemo-mechanical preparation (CMP) associated with passive ultrasonic irrigation (PUI) using 6% sodium hypochlorite (NaOCl), 2% chlorhexidine gel + saline solution (2% CHXg + SS), 2% chlorhexidine solution (2% CHXs) and SS alone. Sixty mandibular premolars with single straight root canals were randomly assigned into 4 groups (n = 15) according to the irrigant used: G1 (PUI + NaOCl), G2 (PUI + CHXg + SS), G3 (PUI + CHXs) and G4 (PUI + SS). CMP was performed with Reciproc R25 files (25/.08) and the debris extruded from each tooth were collected in pre-weighted Eppendorf tubes and dried in oven at 68°C for 5 days. The average weight of debris was assessed by using an analytical microbalance. ANOVA and post-hoc Tukey’s test were used for statistical analysis (? = 0.05). Debris extrusion was observed in all groups, irrespective of the irrigat used. 2% CHXg + SS was associated with lower debris extrusion compared to the other root canal irrigants (p < 0.05). No significant differences were observed between 6% NaOCl, 2% CHXs and SS. In conclusion, PUI did not completely prevent extrusion of debris. PUI performed with 2% CHXg + SS significantly minimized debris extrusion compared to 6% NaOCl, CHXs and SS.