In Vitro Comparison of Antimicrobial Effectiveness of some New Final Irrigants in Human Root Canals

Abstract

Objective: Final root canal irrigation stands as an effective strategy for eliminating the dentin infection. This study aimed to investigate and compare the antibacterial efficacy of five final irrigation regimens in reducing Enterococcus faecalis within human root canals.

Materials and Methods: 60 Single-canal human teeth contaminated with E. faecalis for 4 weeks were prepared chemomechanically by ProTaper system and sodium hypochlorite (NaOCl). Then, the teeth were randomly assigned into six groups according to the final irrigation protocols: (1) EDTA/NaOCl, 17% EDTA followed by 5.25% NaOCl; (2) EDTA/chlorhexidine (CHX), 17% EDTA followed by 2% CHX; (3) EDTA/cetrimide (CTR), 17% EDTA followed by 2% CTR; (4) MTAD; (5) QMix; and (6) control, 0.9% saline. Bacterial samples collected before instrumentation and after final irrigation were cultured and the colony-forming units (CFUs) were counted.

Results: The statistical analysis showed the CFUs in the QMix, EDTA/CHX, and EDTA/CTR groups were significantly lower than those in the EDTA/NaOCl group. No significant differences were observed between the QMix, EDTA/CHX, and EDTA/CTR groups. MTAD showed weaker ability than QMix and EDTA/CHX to eliminate E. faecalis, but it caused a greater reduction in CFU than EDTA/NaOCl (P<0.05).

Conclusion: The antimicrobial activity of QMix was comparable to that of EDTA/CHX and EDTA/CTR and more effective than that of EDTA/NaOCl against intracanal E.