Efficacy of varying concentrations of subgingivally delivered metformin in the treatment of chronic periodontitis: a randomized controlled clinical trial.

Background: Metformin (MF), a second-generation biguanide, is a commonly used oral antidiabetic drug that has been shown recently to stimulate osteoblasts and reduce alveolar bone loss. The present study aims to explore the efficacy of 0.5%, 1%, and 1.5% MF gel as a local drug delivery system in adjunct to scaling and root planing (SRP) for treatment of intrabony defects (IBDs) in patients with chronic periodontitis.

Methods: A total of 118 IBDs were treated with 0.5%, 1%, or 1.5% MF gel or placebo gel. Clinical parameters (modified sulcus bleeding index, plaque index, probing depth [PD], and clinical attachment level [CAL]) were recorded at baseline, 3 months, and 6 months, whereas radiographic parameters were recorded at baseline and 6 months. IBD depth at baseline and 6 months was calculated on standardized radiographs by using the image analysis software. The mean concentration of MF in gingival crevicular fluid was estimated by reverse-phase high-performance liquid chromatography.

Results: Mean PD reduction and mean CAL gain was found to be greater in MF groups than the placebo group at both 3 and 6 months. Furthermore, significantly greater reduction of IBD depth was found in the MF groups compared to the placebo group, with greatest reduction in 1% MF.

Conclusions: The results of the present study show that local delivery of MF into the periodontal pocket stimulated significant increase in the PD reduction, CAL gain, and improved IBD depth reduction compared to placebo in adjunct to SRP. This can provide a new direction in the field of periodontal healing.