Antimicrobial Effect of Ozone on Cariogenic Microorganisms In Vitro

The aim of this study was to examine the antibacterial effect of ozone on cariogenic microorganisms. Streptococcus salivarius, Streptococcus mutans, Lactobacillus acidophilus, Lactobacillus casei and Actinomyces viscosus were used to test the antimicrobial activity of ozone. The microorganisms were exposed to power levels 2, 3, or 4 of an ozone device for 20, 40, 60, or 120 s. CFU numbers of bacteria were counted after the ozone application; as a result, the number of bacterial cells was decreased. The bacterial cells were also evaluated with a fluorescence microscope. This analysis revealed that some bacterial cells were killed instantaneously in ozone. The electron microscopic analysis showed no difference in surface morphology between bacteria to which ozone had been applied and those to which it had not.