Antimicrobial effectiveness of electro-chemically activated water as an endodontic irrigation solution

Abstract

The use of sodium hypochlorite (NaOCI) as an endodontic irrigation solution is effective in eliminating microorganisms from the root canals of human teeth. The purpose of this in vitro study was to evaluate the antimicrobial effectiveness of electro-chemically activated water (ECA) as an endodontic irrigation solution. ECA is a solution comprising many different ions, molecules and radicals. Sixty caries-free, single root, adult, maxillary, anterior human teeth were used. The root canals were instrumented and irrigated with NaGCI in a similar method to that employed for in vivo root canal treatment. The external root surface of each tooth was sealed and the access cavity kept patent so that root canals could be inoculated with a suspension containing four bacterial. The teeth were randomly divided into four groups (n=15). Each group was irrigated ultrasonically, using solutions of distilled water (control), NaOCI (3.5%), and ECA, the latter at pH's 7.0 and 9.0 respectively. Antimicrobial effectiveness was established directly after irrigation and again seven days later, by counting colony forming units on blood agar plates and by spectrophotometric analysis. The surfaces of the root canals were visually examined by means of scanning electron microscopy. Large numbers of bacteria were present in the canals of teeth irrigated with distilled water. No bacteria were observed following irrigation with NaGCI. Neither of the ECA solutions were found to be effective against all the bacteria. Although some reduction in the number of bacteria was evident in the ECA groups, this was not statistically significant (p>0.05). Within the confines of this study ECA did not demonstrate antimicrobial effectiveness.