Analysis of antimicrobial efficacy of sodium hypochlorite and ozonated water against biofilm in oval canals

Abstract

This in vitro study compared the antimicrobial efficacy of 2.5% sodium hypochlorite (NaOCI) and 8 pg/mL ozonated water agitated by passive ultrasonic irrigation (PUI) or PUI combined with EndoActivator (EA) against mature multispecies biofilm. One hundred and five oval-shaped mandibular premolars were instrumented, sterilized, and inoculated with Enterococcus faecalis, Candida albicans, and Staphylococcus aureus, divided into: Control group - saline; O3 group - ozonated water; O3 PUI group - ozonated water with PUI agitation; O3 PUI+EA group - ozonated water with PUI+EA agitation; NaOCI group - NaOCI; NaOCI PUI group - NaOCI with PUI agitation; and NaOCI PUI+EA group - NaOCI with PUI+EA agitation. Microbiological samples were collected before (Si) and after (S2) the disinfection procedures and the data were statistically analyzed using the Kruskal-Wallis test. In the culture method, there was significant disinfection in the O3 PUI+EA, NaOCI, NaOCI PUI, and NaOCI PUI+EA groups (p<0.05). The combination of NaOCI with PUI+EA reduced microbial counts to zero (p<0.05). In the qPCR method, there was a significant reduction in the total count of viable microorganisms in the O3 PUI, O3 PUI+EA, NaOCI, NaOCI PUI, and NaOCI PUI+EA groups (p<0.05). It can be concluded that 2.5% NaOCI with and without agitation, as well as 8 pg/mL ozonated water with its action enhanced by the agitation techniques, were effective in root canal disinfection, and their antimicrobial efficacy is related to the microorganisms present in the biofilm.