Abstract
Melatonin is produced by the pineal gland and plays a role in regulating circadian rhythm. It influences the physiologic processes, such as the activation of the immune system and the antioxidant function. Melatonin has been reported in the samples of patients with periodontitis. Therefore, the role of melatonin in periodontal diseases must be appraised. Using the strategy of electronic search of various databases, we included studies, published until December 2021, measuring the expression of melatonin in patient samples and evaluating the effect of periodontal therapy on melatonin expression. This review also included studies evaluating the effect of melatonin supplementation on periodontal parameters. In total, 15 articles fulfilled the study inclusion criteria. The results revealed that melatonin is negatively correlated with the severity of periodontal diseases, and melatonin supplementation reduces the levels of periodontal inflammatory parameters. Hence, melatonin has a role in periodontal diseases, but additional studies are warranted to substantiate its use as a biomarker and host modulatory agent.