Adjunctive use of Streptococcus salivarius M18 probiotic in the treatment of periodontitis: a randomized controlled trial.

2025-05-28
3 Biotech 15(6)

PubMed: 40443548
DOI: 10.1007/s13205-025-04363-w

Study Design

Type: Randomized Controlled Trial (RCT)
Sample size: n = 55
Population: 55 participants with stage III or IV periodontitis
Methods: This randomized double-blind placebo-controlled clinical trial evaluated the adjunctive use of Streptococcus salivarius M18 probiotic lozenges following non-surgical periodontal therapy (NSPT) for 12 weeks, with clinical assessments at baseline, immediately after treatment, and at 12 and 24 weeks, plus microbial analysis of subgingival plaque samples.

This randomized double-blind placebo-controlled clinical trial aimed to evaluate the adjunctive use of Streptococcus salivarius M18 probiotic lozenges in the treatment of periodontitis. Following non-surgical periodontal therapy (NSPT), 55 participants with stage III or IV periodontitis were administered either S. salivarius M18 lozenges (test group) or a placebo for 12 weeks. Clinical assessments, including pocket probing depth (PPD), clinical attachment loss (CAL), bleeding on probing (BoP), and plaque index (PI), were performed at baseline (before treatment), immediately after treatment, and during post-treatment follow-ups at 12 and 24 weeks. Microbial analysis was conducted on the subgingival plaque samples collected. The test group demonstrated significantly improved PPD, BoP, and PI compared to the placebo group at post-treatment follow-ups, although no significant difference was observed in CAL. Microbiological analysis revealed a reduction in periodontal pathogens or a shift in the subgingival microbiota toward a decreased pathogenic profile in the test group. This trial is the first to demonstrate the safety and efficacy of S. salivarius M18 as an adjunctive treatment for periodontitis, supporting its potential for broader clinical use in managing periodontal health.

Supplementary information

The online version contains supplementary material available at 10.1007/s13205-025-04363-w.

Research Insights

Supplement	Dose	Health Outcome	Effect Type	Effect Size	Source
Streptococcus salivarius BLIS M18	—	Improved Periodontal Health	Beneficial	Moderate	View source The test group demonstrated significantly improved PPD, BoP, and PI compared to the placebo group at post-treatment follow-ups, although no significant difference was observed in CAL.
Streptococcus salivarius BLIS M18	—	Reduced Periodontal Pathogen Burden	Beneficial	Moderate	View source Microbiological analysis revealed a reduction in periodontal pathogens or a shift in the subgingival microbiota toward a decreased pathogenic profile in the test group.
Streptococcus salivarius M18	—	Improved Periodontal Clinical Parameters	Beneficial	Moderate	View source The test group demonstrated significantly improved PPD, BoP, and PI compared to the placebo group at post-treatment follow-ups, although no significant difference was observed in CAL.
Streptococcus salivarius M18	—	Reduced Periodontal Pathogen Burden	Beneficial	Moderate	View source Microbiological analysis revealed a reduction in periodontal pathogens or a shift in the subgingival microbiota toward a decreased pathogenic profile in the test group.