Gels as adjuvant to non-surgical periodontal therapy: A systematic review and meta-analysis

Objective: This systematic review and meta-analysis evaluated the effect of the use of available drugs loaded gels used as adjunct to non-surgical periodontal therapy.Methods: Systematic research on PubMed/MEDLINE, Cochrane Central register of Controlled Trials, and Embase databases up to December 2021 was performed. Randomized clinical trials (RCT) which compared the outcomes of scaling and root planing (SRP) + local adjuvant administration (gel) versus SRP + placebo or SRP alone in Humans were included. The primary outcome measures were PPD and CAL changes at 3 months.Results: After articles screening, 77 articles were included and assessed for quality. Then, a meta-analysis was conducted in studies with at least 3 months of follow-up. Clinical improvements were found to be significant for tetracyclines (-0.51 [-0.71;-0.31] p < 0.001), macrolides (-0.71 [-1.04;-0.38] p < 0.001), statins (-0.84 [-0.98;-0.70] p < 0.001), metformin (-1.47 [-1.66;-1.29] p < 0.001) and hyaluronan (-1.61 [-2.28;-0.94] p < 0.001) loaded gels, but non-significant for chlorhexidine (-0.48 [-1.10; 0.14] p = 0.13), metronidazole (-0.50 [-1.20; 0.20] p = 0.16) and bisphosphonates (-0.42 [-1.39; 0.54] p = 0.539) gels.Conclusion: Adjunctive use of drugs loaded gels to non-surgical periodondal treatment could improve PPD reduction at 3 months. However, huge disparities remain when comparing the outcomes of the differents drugs used. Future comparative studies should be considered to determine precisely short and long term benefits of such treatments.