A Systematic Review and Meta-analysis of Clinical, Immunological, and Microbiological Shift in Periodontitis After Nonsurgical Periodontal Therapy With Adjunctive Use of Probiotics

Objectives: There is a lack of evidence regarding long-term effects of probiotics as adjuncts to nonsurgical 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 of follow-up.

Methods: Electronic searches of 5 databases were performed. Clinical trials that compared the adjunctive use of probiotics in NSPT with NSPT alone, reporting clinical or immunological 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: Ten randomized controlled trials were included, and high heterogeneity in methods was noted. Meta-analysis revealed CAL gain, and PPD reduction in the probiotics group was 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 pathogen levels between groups at 3 months. Immunological data were not sufficient for quantitative analysis. Ancillary sensitivity analysis indicated a subset of studies with severe mean baseline PPD (≥5 mm) 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.