ABSTRACT
Objective:To analyze the effects of melatonin administration on the periodontal tissues of rats, linked or not with ligature-induced periodontal disease. Materials and Methods:40 male Wistar rats aged eight weeks, divided into Control Group (GCON), Ligature Group (GLIG), Melatonin Group (GMEL)and Ligature and Melatonin Group (GLIGMEL). GLIG and GLIGMEL were induced to experimental periodontitis by placing a ligature on the lower molars for 30 days. During the experiment, after 16 days with the ligature, melatonin was administered orally for 10mg/kg for 14 days in GMEL and GLIGMEL. In the end, euthanasia was performedand the hemi-mandibles were collected for the respective histological and radiographic analyzes; for the results, Shapiro-Wilk, ANOVA-One-Wayand Tukey's multiple comparison tests were used. Results:A significantly lower alveolar bone loss (p<0.05) was demonstrated in the animals that received the administration of melatonin, in which it had a prophylactic function against the effects of the disease, evidenced in radiographic, histomorphometric and histological analyzes in the bone cell count. Conclusion:Results show that the therapy with administration of melatonin promotes a protective effect on the alveolar bone tissue of rats with induced experimental periodontitis