Lactobacillus reuteri and Reduced Probing Pocket Depth

Research synthesisModerate evidenceMixed effect size3 studies · 2 beneficial · 1 neutral · 0 harmful

Across 3 studies, 2 reported beneficial effects (moderate to large) of Lactobacillus reuteri on reducing probing pocket depth, while 1 high-quality RCT found no significant difference from placebo. The most-studied form was lozenges, but specific CFU doses varied. Effects were observed in patients with periodontitis or peri-implantitis over a median duration of 56 days.

Studied populations: patients with periodontitis (stage III/IV) or peri-implantitis

Caveats: Evidence base is small (only 3 studies) — conclusions should be considered preliminary. One high-quality RCT (evidence score 5) found no significant benefit over placebo, indicating possible inconsistency. Populations varied across studies (residual pockets, generalized periodontitis, peri-implantitis), limiting generalizability. Dose information was incomplete; CFU content was not consistently reported.

Generated Jul 9, 2026

Doses used in studies

lozenges/day: 2 (median 2, IQR 2–2) — 1 study

Time to effect

Median: 7.9 weeks · IQR 5.5 weeks–10.4 weeks · Range 3 weeks–3 months — Reported in 2 of 3 studies

3 of 3 papersPopulation:

Clinical and microbiological effectiveness of limosilactobacillus reuteri in supportive periodontal therapy: randomized clinical trial.
- 2025-08-26
- RCT
- Clinical oral investigations 29(9)
- - Magda Mensi
  - Eleonora Scotti
  - Silvia Marchetti
  - Annamaria Sordillo
  - Gianluca Garzetti
  - Stefano Calza
  - Mark J Buijs
  - Egija Zaura
  - Bernd W Brandt
- PubMed: 40856866
- DOI: 10.1007/s00784-025-06508-w
6 Insights on
- Reduced Probing Pocket Depth
- High evidence
- Clinical
Both groups showed a significant decrease in PPD, BOP, CAL, and number/percentage of residual pockets compared to baseline. However, no inter-group differences were noted.
Effect
Neutral
Effect size
Small
Significant
No
Dose
3 weeks of bi-daily supplementation with lozenges containing probiotic (specific CFU not stated in abstract)
Clinical efficacy of Lactobacillus reuteri-containing lozenges in the supportive therapy of generalized periodontitis stage III and IV, grade C: 1-year results of a double-blind randomized placebo-controlled pilot study
- 2019-10-16
- RCT · n = 20
- Clinical Oral Investigations 24(6)
- - M. G. Grusovin
  - S. Bossini
  - S. Calza
  - V. Cappa
  - G. Garzetti
  - E. Scotti
  - E. Gherlone
  - M. Mensi
- PubMed: 31620939
- DOI: 10.1007/s00784-019-03065-x
5 Insights on
- Reduced Probing Pocket Depth
- High evidence
more PPD reduction at all time points (p < 0.05) ... were found in the probiotic group
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Dose
2 lozenges/day
Impact of Subgingival Lactobacillus reuteri Probiotic Therapy on Clinical Outcomes and Porphyromonas gingivalis Quantification in Peri-Implant Disease: A Prospective RT-PCR-Based Clinical Study.
- 2026
- RCT · n = 26
- Journal of long-term effects of medical implants 36(1)
- - Karthick Kamalakannan
  - Arvina Rajasekar
- PubMed: 41662654
- DOI: 10.1615/jlongtermeffmedimplants.2025060737
5 Insights on
- Reduced Probing Pocket Depth
- High evidence
- Clinical
Group 2 exhibited significantly greater reductions in PI, GI, PPD, CAL, and P. gingivalis levels compared with Group 1 (P = 0.00)
Effect
Beneficial
Effect size
Large
Significant
Yes
Dose
not specified

Lactobacillus reuteri and Reduced Probing Pocket Depth

Clinical and microbiological effectiveness of limosilactobacillus reuteri in supportive periodontal therapy: randomized clinical trial.

Clinical efficacy of Lactobacillus reuteri-containing lozenges in the supportive therapy of generalized periodontitis stage III and IV, grade C: 1-year results of a double-blind randomized placebo-controlled pilot study

Impact of Subgingival Lactobacillus reuteri Probiotic Therapy on Clinical Outcomes and Porphyromonas gingivalis Quantification in Peri-Implant Disease: A Prospective RT-PCR-Based Clinical Study.