Comparative Evaluation of Antimicrobial Efficacy of Sodium Hypochlorite, MTAD, and Tetraclean Against Enterococcus faecalis Biofilm

The aim of this study was to compare the antimicrobial efficacy of 5.25% NaOCl, BioPure MTAD (Dentsply Tulsa Dental, Johnson City, TN), and Tetraclean (Ogna Laboratori Farmaceutici, Milano, Italy) against Enterococcus faecalis biofilm generated on cellulose nitrate membrane filters. After incubation, the membrane filters were transferred into tubes containing 5 mL of the selected antimicrobial solution test agent or NaCl 0.9% (positive control) and incubated for 5, 30, and 60 minutes at 20°C. After each period of time, the test agents were vortexed for 60 seconds to resuspend the microorganisms. Ten-fold serial dilutions were generated in reduced transport fluid. Each dilution was plated onto a brain heart infusion plates. The plates were then incubated for 48 hours in an aerobic atmosphere at 37°C and colony-forming units per membrane was calculated. Statistical analysis showed that only 5.25% NaOCl can disgregate and remove the biofilm at every time; however, treatment with Tetraclean caused a high degree of biofilm disgregation in every considered time intervals as compared with MTAD (T5 p < 0.05, T30 p < 0.01, and T60 p < 0.001).