A systematic review and meta-analysis of clinical, immunological and microbiological shift in periodontitis after non-surgical periodontal therapy with adjunctive use of probiotics

Abstract Objectives There is a lack of evidence regarding long-term effects of probiotics as adjuncts to non-surgical periodontal therapy (NSPT) in the management of periodontitis. Therefore, this systematic review aimed to evaluate the clinical, microbiological, and immunological outcomes of probiotics applied as an adjunct to NSPT with at least 3 months follow-up. Methods Electronic searches of five databases were performed. Clinical trials that compared the adjunctive use of probiotics in NSPT with NSPT alone, reporting clinical, immunological and/or microbiological outcomes were selected. The primary clinical outcome variables were clinical attachment level (CAL) and probing pocket depth (PPD). Meta-analyses were conducted to evaluate the efficacy of probiotics over different longitudinal intervals. Results 10 RCTs were included and high heterogeneity in methods was noted. Meta-analysis revealed CAL gain and PPD reduction in the probiotics group were significant at 3 months and 12 months, but no significant difference was noted at 6 months and 9 months. There was no significant difference in periodontal pathogens levels between groups at 3 months. Immunological data was not sufficient for quantitative analysis. Ancillary sensitivity analysis indicated a subset of studies with severe mean baseline PPD (≥ 5mm) at baseline showed significant and more CAL gain and PPD reduction at 3 months, with probiotics administration of 2-4 weeks. Conclusion Heterogenous evidence implied a long-term clinical benefit of probiotics as an adjunct to NSPT. Outcomes may be impacted by baseline disease severity. Limited microbiological and immunological data precluded any conclusive findings. Current evidence is insufficient to formulate clinical recommendations.