Researchers have found in a new study that adjunctive melatonin therapy significantly improves glycemic control in patients with type 2 diabetes mellitus (T2DM) and periodontitis. These findings suggest melatonin may serve as a safe host-modulatory treatment, though larger trials are needed to establish optimal dosing and long-term metabolic benefits.Melatonin has demonstrated anti-inflammatory, antioxidant, and immunomodulatory properties, making it a potential adjunct in periodontal therapy. However, its systemic metabolic effects, particularly on glycemic control in patients with type 2 diabetes mellitus (T2DM) and periodontitis, remain unclear. A study was done to evaluate the impact of adjunctive melatonin in nonsurgical periodontal therapy on glycated hemoglobin (HbA1c) levels in patients with T2DM and periodontitis. Materials and Methods: A systematic search was conducted in PubMed, EMBASE, and the Cochrane Library through July 2025. Randomized controlled trials comparing scaling and root planing (SRP) with adjunctive melatonin versus SRP alone or with placebo were included. The primary outcome was the change in HbA1c levels. Data were pooled using a random-effects model in Review Manager 5.4, and risk of bias was assessed using the Cochrane RoB 2 tool. Results: Of 79 records screened, 3 randomized controlled trials (214 participants) met the eligibility criteria. Meta-analysis revealed a significant reduction in HbA1c levels with adjunctive melatonin compared to control (Mean Difference: – 1.08%; 95% CI: – 1.61 to – 0.55; p < 0.0001), despite substantial heterogeneity (I[2] = 91%). No serious adverse events were reported. Adjunctive melatonin therapy significantly improves glycemic control in patients with T2DM and periodontitis. These findings highlight melatonin’s potential as a safe and biologically plausible host-modulatory agent. Further large-scale trials are needed to determine optimal dosing and long-term metabolic outcomes.Reference:Sampaio, Pedro, et al. “Impact of Adjunctive Melatonin in Periodontal Therapy On Glycated Hemoglobin Levels in Patients With Type 2 Diabetes and Periodontal Disease: a Systematic Review and Meta-analysis.” Odontology, 2026.Keywords:melatonin, safe, host-modulatory, treatment, dosing, long-term, metabolic, benefits, Melatonin Adjunct Therapy, Improves, Glycemic Control, T2DM, Periodontitis, Sampaio, Pedro