Relationship between Salivary Melatonin Level and Periodontal Diseases

Statement of the problem: Melatonin has powerful antioxidant effects, has an immunomodulatory role, stimulates the synthesis of type I collagen fibers, and promotes bone formation. Melatonin is also secreted in the saliva, although its role in the mouth is not known well. Purpose: The aim of this study was to examine the correlation between salivary melatonin level and periodontal diseases. Materials and methods: Fifty subjects with a mean age of ۴۰.۴۴±۶.۳۸ years were equally divided into ۵ groups: ۱۰ healthy subjects, ۱۰ subjects with gingivitis, ۱۰ subjects with localized moderate chronic periodontitis, ۱۰ subjects with generalized moderate chronic periodontitis and ۱۰ subjects with generalized severe chronic periodontitis. Saliva samples were collected from all the subjects and melatonin levels were determined using an enzyme-linked immunosorbent assay. Two-way and one-way ANOVA and Tukey test were used to analyze relationships between the variables. Results: Healthy subjects had significantly higher salivary melatonin level (۵.۲۹±۰.۵۰ pg/mL) compared to patients with gingivitis (۴.۳۵±۰.۳۰ pg/mL) (P<۰.۰۰۱). The difference between salivary melatonin level in patients with gingivitis and periodontitis was significant (P<۰.۰۰۱). Level of melatonin in patients with generalized severe chronic periodontitis (۳.۳۹±۰.۱۰ pg/mL) was significantly lower than that in other groups (P<۰.۰۱). Conclusion: This study showed that salivary melatonin level in patients with periodontal diseases is lower than that in healthy subjects, and it has a negative correlation with the severity of disease, suggesting that melatonin might have a protective role against periodontal diseases, although further research is required to validate this hypothesis.