Bactericidal Activity of a Stabilized Chlorine Dioxide rinse

Objectives: CloSYSII is a novel antibacterial rinse that has a stabilized chlorine dioxide formulation. The purpose of this study was to determine bactericidal activity against polymicrobial suspensions containing both gram-positive and negative anaerobes. Methods: The following bacteria were used in this study: Actinomyces viscosus, Streptococcus sanguinis, S. oralis, Enterococcus faecalis, Campylobacter rectus, Fusobacterium nucleatum, Peptostreptococcus micros, and Porphyromonas gingivalis. Bacteria were cultured in enriched TSB-YE under anaerobic conditions. Standardized, polymicrobial suspensions were prepared at concentrations of 106 cfu/ml using predetermined standard curves. Both singular and multiple exposure treatment regimens were done with single exposures consisting of 30 seconds to 2 minutes. The multiple exposure treatment regimen consisted of polymicrobial suspensions exposed 3x throughout the day. Suspensions were maintained in artificial saliva supplemented with dilute tryptone and Yeast extract and incubated anaerobically at 370 between exposures. Aliquots were removed from replicate tubes and diluted into Neutralizing Broth. Samples were spiral-plated onto several selective/differential media for isolation of each organism in the polymicrobial suspensions. Determination of numbers of viable bacteria was done following standard spiral-plating methodology. Data were analyzed via repeated measures ANOVA. Results: Single exposure resulted in modest reductions in bacteria (0.5-1.0 logs) within the polymicrobial suspensions, but none were significant. However, multiple exposures of the polymicrobial suspensions resulted in dramatic changes in the composition. A key finding was that we observed an almost complete elimination of the gram-negative anaerobes (5-6 log decreases, p<0.01). Conclusion: A 3x exposure regimen of polymicrobial suspensions containing bacteria associated with oral health and periodontal disease with a stabilized chlorine dioxide rinse significantly reduced levels of gram-negative anaerobes. Supported by Rowpar Pharmaceuticals, Inc.