Locally delivered 1% metformin gel improves periodontal parameters: A systematic review and meta-analysis.

Purpose: Approximately 19% of the global adult population is affected by periodontal diseases. Healing is a protracted process that is significantly influenced by the patient's motivation, proficiency, and cooperation. The prevalence of periodontal diseases in patients with diabetes mellitus is extremely high, and the relationship is bidirectional. In previous investigations, metformin (MF), a biguanide antidiabetic medicine, has demonstrated promising results when administered locally to periodontal defects. The study aimed to systematically assess available literature that evaluate the effectiveness of 1% metformin gel in the treatment of periodontal disease. We attempted to include clinical trials on patients with periodontitis treated with local administration of 1% metformin gel, compared to a placebo.

Methods: Using identical MeSH terms, we conducted a systematic search in three databases. Our analysis encompassed human studies that measured the periodontal pocket depth, the clinical attachment level, and the depth of the intra-bony defect. Meta-analyses were carried out using random effects model to compare the mean differences between the study group, which received 1% MF gel locally in addition to traditional scaling and root planing (SRP), and the control group, which received a placebo in addition to conventional treatment.

Results: Following the selection procedure, six articles were selected for inclusion in our meta-analysis, out of the 246 articles identified through the systematic search. After three and six months of follow-up, meta-analyses revealed statistically significant differences between the control and study groups. The overall effect for PD was a 1.33 mm reduction (95% confidence interval (CI): -1.66; -1.01) after three months and 1.87 mm (-2.24; -1.39) after six months. The overall effect of CAL was 1.80 mm (-2.26; -1.34) after three months and 2.14 mm (-2.71; -1.58) after six months. The change in IBD after a six-month follow-up was 1.16 mm (-1.40; -0.92).

Conclusion: The application of 1% MF gel enhances the healing process in periodontal diseases, when employed in conjunction with conventional therapy.