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Each row is one question a systematic review asked: who, what, compared with what, and which outcome, with the effect it found and how certain that is. Words match anywhere in the field.

Limit to evidence status or GRADE (optional)

12 questions in 2 reviews · cluster CL0241

current versions
No studies 0 · 0%Ungraded 8 · 66.7%Very low 3 · 25%Low 0 · 0%Moderate 1 · 8.3%High 0 · 0%

Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.

Intervention categories, outcome domains and clusters are a proposed key pending human validation. Clear all filters

QuestionEffectEvidenceStatus / GRADE
Postbiotics from Lactobacillus spp. (cell-free supernatants, biosurfactants, lipoteichoic acid, bacterial lysates) vs Untreated control
Downregulation of S. mutans virulence/biofilm gene expression (gtfB, gtfC, ftf) · Cariogenic bacteria (mainly Streptococcus mutans reference strains) and oral biofilms in vitro · Exposure 24 h to 7 days
Postbiotics and Dental Caries: A Systematic Review. (2025)
Postbiotics downregulated expression of S. mutans virulence and exopolysaccharide-synthesis genes (e.g., gtfB, gtfC, gtfD, ftf) in 10 in vitro studies; no pooled estimate.8 studiesUngraded
Postbiotics from Lactobacillus spp. (cell-free supernatants, biosurfactants, lipoteichoic acid, bacterial lysates) vs Untreated control
Proposed inhibition of S. mutans adhesion to tooth surface (mechanism; direct adherence endpoint confirmed only in Ahn 2018) · Cariogenic bacteria (mainly Streptococcus mutans reference strains) and oral biofilms in vitro · Exposure 24 h to 7 days
Postbiotics and Dental Caries: A Systematic Review. (2025)
Postbiotics (mainly biosurfactants and lipoteichoic acid) interfered with S. mutans adhesion to tooth/hydroxyapatite surfaces in 5 in vitro studies; no pooled estimate.5 studiesUngraded
Lactobacillus-derived postbiotics vs Not specified
Streptococcus mutans growth and biofilm formation · Reference strains of Streptococcus mutans and cariogenic biofilms · 24 h to 7 days
Postbiotics and Dental Caries: A Systematic Review. (2025)
no estimate extracted12 studiesUngraded
Heat-killed probiotic and postbiotic oral lozenges vs Placebo
Reduced dental plaque index · Adults with dental caries · 4 weeks
Postbiotics and Dental Caries: A Systematic Review. (2025)
One RCT in adults reported a significant reduction in plaque index with postbiotic/heat-killed lozenges versus placebo (Lin 2022); no pooled estimate.1 studyUngraded
Heat-killed probiotic and postbiotic oral lozenges vs Placebo
Salivary Streptococcus mutans count and plaque index · Adults with dental caries · 4 weeks
Postbiotics and Dental Caries: A Systematic Review. (2025)
no estimate extracted1 studyUngraded
Milk-based probiotic vs No treatment or placebo (control)
Bacterial plaque index · Children and/or adolescents (<18 years) without background systemic disease · Probiotic presentation: milk (vs other presentations; p-interaction=0.01)
Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024)
MD -0.10 [-0.20, 0]NRUngraded
Mouth-rinse probiotic vs No treatment or placebo (control)
Salivary pH · Children and/or adolescents (<18 years) without background systemic disease · Probiotic presentation: mouth rinse (vs other presentations; p-interaction<0.01)
Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024)
MD -0.40 [-0.54, -0.26]NRUngraded
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control)
Lactobacillus count (CFU/mL) · Children and/or adolescents (<18 years) without background systemic disease · follow-up: mean 5.2 months, Overall (all presentations pooled)
Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024)
MD -0.78 [-1.65, 0.09]6 studies · 1143 participantsVery low
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control)
Salivary pH · Children and/or adolescents (<18 years) without background systemic disease · follow-up: mean 1.1 months, Overall (all presentations pooled)
Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024)
MD -0.12 [-0.72, 0.48]3 studies · 137 participantsVery low
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control)
Streptococcus mutans count (CFU/mL) · Children and/or adolescents (<18 years) without background systemic disease · follow-up: mean 4.4 months, Overall (all presentations pooled)
Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024)
MD -0.40 [-0.57, -0.24]11 studies · 1321 participantsModerate
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control)
Bacterial plaque index · Children and/or adolescents (<18 years) without background systemic disease · follow-up: mean 2.3 months, Overall (all presentations pooled)
Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024)
MD 0.21 [-0.55, 0.96]4 studies · 171 participantsVery low
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control)
Streptococcus viridans count (CFU/mL) · Children and/or adolescents (<18 years) without background systemic disease · 6 months, Single study (Mishra 2014); not pooled
Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024)
MD 0.40 [0.33, 0.47]1 study · 60 participantsUngraded