Disinfective Effect of the Ultra Sonic Ozone Washer.

The disinfecting effects of an ultra sonic ozone washer were evaluated in antiseptic-resistant strains of methicillin-resistant Staphylococcus aureus (MRSA). Two antiseptic-sensitive strains and two antiseptic-resistant strains were killed after treatment with the washer. (The leakage of the ozone gas from the washer was not detected.) The resin-plates to which gingival bacteria, Candida albicans and gingivalis bacteria, Streptococcus sanguis, adhered, were used as a model for the washing of an artificial tooth. The numbers of these bacteria detected before the washing, were both 107 cfu/ml while those detected in washing water before washing with ozonized water were respectively none and 104 cfu/ml. Only 10-20 colonies were grown on the resin-plates of both bacteria. A resin-plate adhering Helicobacter pylori, which is presumed to be associated with active chronic gastritis and duodenal ulcer diseases, was also tested. Bacteria of 108 cfu/ml before the washing was not detected in washing water after washing with ozonized water. Only 10-20 colonies were grown on the resin-plate. These results clearly confirmed that the ultra sonic ozone washer are a useful means for disinfecting instruments and devices contaminated with antisepticresistant strains of MRSA and an artificial tooth.