Document Type : original article
Authors
1 School of Dentistry, Zanjan University of Medical Sciences, Zanjan, Iran.
2 Department of Biostatistics and Epidemiology, Faculty of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran.
Abstract
Background: Nitric oxide (NO) is a highly active radical that prevents the growth of oral bacteria by inhibiting their growth and increasing the cytotoxicity of salivary macrophages as a non-specific defense mechanism. The aim of this study was to investigate the salivary NO concentration and its relationship with the DFS caries index and salivary pH in children.
Materials and Methods: In a cross-sectional study, 177 children aged 4-12 years with different levels of DFS were selected. 2 ml of unstimulated saliva was collected from each child, and the pH and NO concentration of the collected saliva were measured using a pH meter and the enzyme-linked immunosorbent assay (ELISA) method, respectively. Statistical analyzes were done with the help of one-way analysis of variance and pairwise comparisons.
Results: The mean concentration of salivary NO in children with severe caries (dfs>8) was significantly lower than in children with mild caries (dfs≤2) (p=0.008). The pH of saliva in children with severe caries (dfs>8) was significantly higher than in children with moderate caries (2 ≥dfs>8) (p=0.027), and in children aged 4-6, it was higher than in children aged 6-9(p=0.039).
Conclusion: Increasing the amount of NO in saliva can decrease decay, as the production of nitrous oxide is actually the body's defense mechanism to neutralize the acids produced by decay-causing bacteria. Salivary pH decreases first and then increases with increasing caries.
Keywords
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