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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.
12 questions in 2 reviews · intervention: Probiotics · outcome domain: Microbiological/plaque
current versionsNo 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
| Question | Effect | Evidence | Status / 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 studies | Ungraded |
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 studies | Ungraded |
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 extracted | 12 studies | Ungraded |
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 study | Ungraded |
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 extracted | 1 study | Ungraded |
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] | NR | Ungraded |
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] | NR | Ungraded |
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 participants | Very 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 participants | Very 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 participants | Moderate |
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 participants | Very 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 participants | Ungraded |