Probiotics for managing caries and periodontitis: Systematic review and meta-analysis

Objectives: Probiotics might be beneficial to prevent or treat caries, gingivitis or periodontitis. We aimed to appraise trials assessing probiotics for managing caries and periodontal disease.

Data: We included randomized controlled trials comparing the efficacy of probiotics versus (placebo) control with regards to Streptococcus mutans [SM], lactobacilli [LB], periodontal pathogens numbers, gingivitis, oral hygiene, caries incidence/experience increment, or periodontitis. Meta-analysis and trial-sequential-analysis were performed.

Sources: Three electronic databases (Medline, Embase, Central) were screened.

Study selection: 50 studies (3247 participants) were included. Studies were mainly performed in children and used lactobacilli (45); bifidobacteria (12) or other genus (3). Probiotics significantly increased the chance of reducing SM (OR: 2.20, 95% CI: 1.23/3.92) or LB (OR: 2.84; 1.34/6.03)<10(4)CFU/ml. Such reduction was confirmed for SM counts (standardized mean differences: -1.18, 95% CI: -1.64/-0.72), but not LB (SMD: 0.33; 0.15/0.52). For periodontal pathogens, no significant difference was found. Probiotics significantly reduced bleeding-on-probing (SMD: -1.15; -1.68/-0.62) and gingival index (SMD: -0.86; -1.52/-0.20), but not plaque index (SMD: -0.34; -0.89/0.21). Caries incidence was not significantly reduced (OR: 0.60; 0.35/1.04), neither was caries experience (SMD: -0.26; -0.55/0.03) or CAL (SMD: -0.46; -0.84/0.08). In contrast, probing-pocket depths (SMD: -0.86; -1.55/-0.17) were significantly reduced. Data was quantitatively insufficient for conclusive findings, and risk of bias was high.

Conclusion: Current evidence is insufficient for recommending probiotics for managing dental caries, but supportive towards managing gingivitis or periodontitis. Future studies should only record bacterial numbers alongside accepted disease markers or indicators.

Clinical significance: Probiotic therapy could be used for managing periodontal diseases. For caries, further studies should ascertain both efficacy and safety.