Bactericidal effects of mouth rinses on oral bacteria.

The bactericidal efficacy of two types of Listerine; Listerine and Cool Mint Listerine, and povidone iodine on oral microorganisms, methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus pyogenes, Helicobacter pylori and Candida albicans were examined. Most of the oral bacteria were killed completely by a 10-sec exposure to Listerine or Cool Mint Listerine. H. pylori, MRSA and C. albicans were also reduced by a 30-sec exposure to the Listerine mouth rinse. Bacteria in dental plaque were decreased by exposure to Listerine, Cool Mint Listerine, and povidone iodine for 30 seconds. Mouthwashing with Listerine for 30 seconds resulted in a decrease to approximately 1/100 of the viable bacterial counts in saliva. These bactericidal effects against bacteria in saliva and dental plaque indicated that Listerine and Cool Mint Listerine antiseptic are useful in oral cavity as antiseptic mouth rinses.