Effect of Ozonated Water on Cultivable Oral Streptococci in ICDAS 5 Cavitated Caries Lesions: A Pre-Experimental Study

Background: Childhood caries has been considered a public health problem due to its high worldwide prevalence and multifactorial etiology, particularly the exacerbated presence of cariogenic microflora, especially Streptococcus mutans (S. mutans). Structurally, it contains high levels of adhesins, which favor its adhesion to the tooth surface. Therefore, the objective of this study is to analyze the antimicrobial effect of ozone on cavitated lesions in the pediatric population by evaluating the presence of S. mutans using Mitis-Salivarius agar. Methods: This was a pre-experimental study conducted in 23 participants with ICDAS 5 cavitated carious lesions diagnosed with reversible pulpitis or involving asymptomatic teeth. Ozonated water was prepared at a concentration of 20 ppm and applied to the cavitated lesions for 120 s; bacterial samples were taken before and after the application of the ozonated water and subsequently cultured on Mitis-Salivarius agar at 37 °C in a 5% CO2 atmosphere for 24 h. Results: Wilcoxon signed-rank test revealed a statistically significant reduction in cultivable oral streptococci counts following application of the ozonated water treatment (Z = −3.00, p = 0.003). Of the 23 samples analyzed, 17 (73.9%) showed a decrease in CFU counts. Conclusions: The results suggest that ozonated water may be a promising alternative for bacterial control in cavitated carious lesions in children; however, evidence is still limited, and there is high variability in the protocols to support its widespread clinical use.