Effectiveness of Oral Microbiome-Targeted Probiotics in Reducing Systemic Inflammation and Periodontal Disease Progression

Abstract

Background: Periodontal disease is a chronic inflammatory condition associated with oral microbial dysbiosis and exaggerated host immune responses. Conventional non-surgical periodontal therapy, primarily scaling and root planing (SRP), may not fully address persistent dysbiosis and inflammation in susceptible individuals. Oral microbiome-targeted probiotics have emerged as a potential adjunctive strategy to improve clinical outcomes and modulate inflammatory pathways in periodontitis. Objective: To evaluate the effectiveness of oral microbiome-targeted probiotics in improving periodontal clinical parameters and modulating inflammatory biomarkers in patients with chronic periodontitis. Methods: A systematic review and meta-analysis was conducted according to PRISMA guidelines. Randomized controlled trials involving adults with chronic periodontitis receiving probiotics as an adjunct to SRP were included. Eligible studies reported changes in probing pocket depth (PPD), clinical attachment level (CAL), and/or inflammatory biomarkers such as IL-1β, IL-8, and IL-10. Data were extracted using a standardized form, and risk of bias was assessed using the Cochrane RoB 2.0 tool. A random-effects model was applied to calculate mean differences (MD) with 95% confidence intervals (Cis) for continuous outcomes. Results: Three randomized controlled trials comprising 99 participants were included. Probiotic strains investigated included Lactobacillus reuteri, Lactobacillus rhamnosus SP1, and Bifidobacterium animalis HN019. Adjunctive probiotics led to greater PPD reduction (MD = −0.35 mm; 95% CI: −0.55 to −0.12) and CAL gain (MD = +0.28 mm; 95% CI: +0.05 to +0.50) compared with SRP plus placebo. Inflammatory analysis from one trial showed a marked reduction in IL-1β (MD = −35 pg/mL; 95% CI: −60 to −12) and a significant increase in IL-10 (MD = +8 pg/mL; 95% CI: +3 to +12), indicating favorable immunomodulation. Conclusion: Adjunctive oral microbiome-targeted probiotics appear to provide additional benefits beyond conventional SRP in chronic periodontitis, improving PPD, CAL, and key inflammatory biomarkers. These findings support the potential role of probiotics as a useful adjunct in non-surgical periodontal therapy. Larger, standardized multicenter trials are warranted to confirm long-term efficacy and define optimal probiotic regimens.