Effectiveness of calcium and sodium hypochlorite in association with reciprocating instrumentation on decontamination of root canals infected with Enterococcus faecalis.

The aim of this study was to evaluate the antimicrobial activity of sodium and calcium hypochlorite utilising reciprocating instrumentation. Sixty root canals were inoculated with E. faecalis for 14 days. Samples were divided into six groups according to decontamination protocol: G1: no treatment, G2: distilled water, G3: 2.5% sodium hypochlorite, G4: 2.5% calcium hypochlorite, G5: 5.25% sodium hypochlorite and G6: 5.25% calcium hypochlorite. Instrumentation was performed with Wave One reciprocating system (Dentsply Sirona Endodontics, York, PA, USA) in groups G2 to G6. Colony-forming units (CFUs) counting was performed and the data were subjected to Anova and Tukey (α  =  0.05). Group 1 and 2 showed the highest mean contamination, with a significant difference between them (P < 0.05). Groups 3, 4, 5 and 6 showed the lowest contamination means with no significant difference between them (P < 0.05). Sodium and calcium hypochlorite, in association with reciprocating instrumentation, can be an effective decontamination protocol in root canals infected with E. faecalis.