Melatonin as an index of periodontal disease

periodontal disease affects the supporting tissues of the tooth. the clinical manifestation varies from gingivitis to periodontitis. periodontal disease is triggered by bacterial infection that releases toxins. the imbalance between oxidants and antioxidants determines the progression of periodontal disease. melatonin (MEL) (N-acetyl-5-methoxytryptamine) is a hormone in the human body. Its production takes place in various organs including the retina, gastrointestinal tract, bone marrow, leukocytes, lymphocytes, skin, and principally pineal gland. its main function is the regulation of circadian and seasonal rhythm, body weight, reproduction, bone metabolism, and tumor growth. an important function of melatonin is the ability to reduce oxidative stress. the aim of this work is to explain if there are differences in salivary melatonin concentration between periodontal and healthy individuals. the study was conducted utilizing the main scientific databases (pubmed, , and web of science). the time window considered for the electronic search w medline as from march 1, 2007, to march 1, 2020. the work takes into account 6 works on the disease. other studies were excluded as they did not meet the inclusion criteria. studies revealed a concentration of salivary melatonin compared to patients with periodontal disease. studies agree that the concentration of melatonin is lower in people with periodontal disease. only one study showed no difference in concentration. melatonin, therefore, has a protective effect on the periodontium thanks to its antioxidant properties. the salivary measurement of melatonin could be a useful tool for early detection. it can also be used as a therapy to improve the symptoms of periodontal disease.