Objective: The aim of this study was to evaluate the antibacterial potential of NAC as an endodontic irrigant on the clinical isolates of the Enterococcus faecalis biofilm.Methods: NAC with a pH of 2.5 and 11 (NAC pH 2.5 and NAC pH 11, respectively) were exposed to clinical isolates of E. faecalis biofilms for 1 min. The NAC samples were compared to 2% chlorhexidine (CHX), which is commonly used as an irrigant in persistent infections. The antibacterial potential of these irrigants was evaluated by comparing the bacterial count of the E. faecalis colonies after they were exposed to the irrigants. Results:The NAC pH 2.5 test group showed a reduction in the E. faecalis colonies, but this reduction was not statistically significant when compared to the 2% CHX group results. The NAC pH 11 test group showed the greatest reduction in bacterial colonies, and this reduction was statistically significant when compared to the NAC pH 2.5 and 2% CHX groups' results. Conclusion:NAC pH 11 has antibacterial potential on the clinical isolates of E. faecalis biofilms.

Methods: Using E. faecalis biofilms from clinical isolate were grown on microtiter well plate, incubated for 24 h and subjected to the following treatments: Natrium hypochlorite 2.5% (5 s), chlorhexidine 2% (5 s), natrium chloride 0.9% (5 s), and the irrigants with additional diode laser irradiation (980 nm, 15 Hz, 1.5 W, 3.5 J, 5 s). The antibacterial effects of the irrigants and diode laser were scored using colony form units (CFU). Results:The clinical isolate colony of E. faecalis that was exposed to a saline solution and diode laser application had the highest score (18700 CFU/ml), while the lowest score (80,00 CFU/ml) was recorded in the group that was exposed to a chlorhexidine 2% irrigant with additional diode laser application. Conclusion:The diode laser had an antibacterial effect on a clinical isolate of E. faecalis biofilm, and this effect was increased when it was used in addition to the application of chlorhexidine 2% and natrium hypochlorite 2.5% irrigants.

Objective: Candida albicans is a predominant fungal species found in persistent root canal infection, and its virulence depends on the ability to formbiofilms. To be able to eliminate this infection, a safe irrigation solution during root canal preparation is needed. This study is conducted to investigatethe antifungal properties of secang heartwood extract solutions on C. albicans biofilm.Methods: C. albicans biofilm was obtained from incubation of C. albicans ATCC 10231 at 96-well plates in 37°C for 24 h. These biofilms were exposedto various treatments: Secang heartwood in three different concentrations (25%, 33%, and 50%), sodium hypochlorite (NaOCl) 2.5%, and controlgroup. The results of the treatment are to see the optical density (OD) value. The higher the OD values, the lower antifungal activity of the solution.Results: The mean OD result from six samples obtained the mean value of various OD values showed in ELISA reader. Antifungal efficacy of 25%secang heartwood was lower than concentration of 33% and 50%. All concentrations of secang heartwood showed higher OD values than 2.5% NaOClbut lower than control group with p=0.01.Conclusion: Secang heartwood possesses antifungal effects against C. albicans biofilm but is lower than 2.5% NaOCl. Concentration of 25% has thestrongest effect against C. albicans among other concentrations. This was a preliminary study of the antifungal efficacy of secang heartwood extractsolutions against C. albicans biofilm. The result indicates that this solution has the potential to be used as an herbal alternative in root canal irrigations.