Nitric oxide modulates levels of salivary Lactobacilli

Abstract

Objective. Nitric Oxide (NO) is one of the most powerful antibacterial compounds. The aim of this study was to determine the association between salivary NO, dental caries and cariogenic bacteria. Materials and methods. The salivary NO concentration of 257 Korean children was analyzed by the Griess colorimetric reaction method. Salivary mutans streptococci (MS) and Lactobacilli (LB) were counted using the Dentocult MS and Dentocult LB kit, respectively. Dental caries status was examined using the WHO criteria. Confounders were age, gender, salivary flow rate and salivary buffer capacity. Analysis of covariance (ANCOVA) was used to evaluate the association among NO, salivary MS level, salivary LB level and dental caries status after adjusting for the effects of confounders. Results. A significant decrease was found in salivary NO levels as the salivary LB count increased after controlling for confounders (p = 0.049). However, the MS level, caries experience and active caries status showed no significant association. Conclusion. This result indicates that NO production might be a host defense mechanism against the growth of cariogenic bacteria.