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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.
75,239 questions in 5,342 reviews
current versionsNo studies 15,213 · 20.2%Ungraded 10,323 · 13.7%Very low 17,528 · 23.3%Low 17,951 · 23.9%Moderate 11,190 · 14.9%High 3,034 · 4%
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.
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Unilateral cleft lip and palate (UCLP) vs Bilateral cleft lip and palate (BCLP) Plaque Index (PI) · Patients with cleft lip and palate (CLP) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | MD -0.13 [-0.38, 0.12] | 2 studies · 117 participants | Ungraded |
Simple childhood caries prediction models with at least two predictors vs No competing model Dental caries discrimination (area under the curve) · Children and adolescents (≤18 years) · Validation assessment; prediction horizon not reported, Wickramasinghe (2022) Risk prediction models for dental caries in children and adolescents: a systematic review and meta-analysis. (2025) | AUC 0.592 [0.514, 0.671] | 1 study | Ungraded |
Genetically predicted pulp and periapical diseases vs Without pulp and periapical diseases (lower genetic liability) Lacunar stroke · European-ancestry adults (GWAS) The contribution of oral infectious diseases in lacunar stroke based on meta-analysis and Mendelian… (2025) | OR 1.20 [1.03, 1.41] | NR | 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 |
Intervention NR Composite: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · HDI: High Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.39 [0.26, 0.58] | 7 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · HDI: Medium Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.29 [0.07, 1.21] | 2 studies | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Osteoporosis with pathological fracture · European GWAS participants · SVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.953 [0.813, 1.117] | 376746 participants | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of fractures (any site) · General population (both sexes, all ages) · Long-term / lifetime fluoride exposure, Drinking-water fluoride 3.0 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 1.19 [0.87, 1.64] | 4 studies | Ungraded |
Intervention NR Specificity · Imaging modality: CBCT Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Specificity 1.00 [0.99, 1.00] | 1 study | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Forearm fracture · European GWAS participants · SVMR Maximum Likelihood From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.990 [0.950, 1.032] | 490889 participants | Ungraded |
Artificial intelligence algorithms for caries detection vs Dental expert or visual-tactile/clinical assessment as reference standard Positive post-test probability · Dental images or diagnostic tests for dental caries detection · Overall (all imaging modalities pooled) Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Post-test probability 0.79 | 20 studies | Ungraded |
Electronic cigarette use vs Non-smokers IL-8 level · People who use electronic cigarettes · GCF The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | no estimate extracted | 1 study | Ungraded |
Self-assembling/remineralizing peptide (e.g., P11-4, PAA-PASP) vs No biomimetic remineralization (control) Immediate (24 h) resin-dentin bond strength (MPa) · Artificial caries-affected dentin (ACAD) in extracted permanent human teeth (in vitro) · 24 h (immediate), Etch-and-Rinse + chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD 4.553 [-0.635, 9.740] | 4 studies | Moderate |
Microinvasive techniques (resin infiltration or glass ionomer varnish) vs Non-invasive measures (fluoride varnish/toothpaste, flossing, oral hygiene instruction, sham/standard of care) Radiographic progression of proximal caries lesions · Children with non-cavitated proximal caries lesions in primary teeth (ages 3-9) · Final follow-up (1 to 2 years across trials), Primary teeth (Fig. 6, subgroup 2.1.2) Microinvasive interventions in the management of proximal caries lesions in primary and permanent teeth-… (2025) | OR 0.38 [0.25, 0.57] | 5 studies · 266 participants | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · HDI: Medium Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.88 [0.14, 5.56] | 2 studies | Ungraded |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) Fracture of lumbar spine and pelvis · European-ancestry adults · Lifelong genetic liability, SVMR (IVW), total causal effect From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.950 [0.810, 1.113] | 490700 participants | Ungraded |
Intervention NR Bacterial count reduction · AR-assisted toothbrush vs manual toothbrushing The Application of Gamification in Children's Oral Health Management: Systematic Review. (2025) | Narrative (P value) Significant reduction in bacterial count with AR-assisted toothbrush (P<.05) | 1 study | Ungraded |
Lacunar stroke (cases) vs Without lacunar stroke (controls) Clinical attachment level (CAL) · Adults The contribution of oral infectious diseases in lacunar stroke based on meta-analysis and Mendelian… (2025) | MD 1.34 [0.63, 2.05] | 4 studies | Ungraded |
Low periodontal-disease prevalence vs Not applicable OHRQoL sum score transformed to 0-100 · Community-dwelling adults aged 60 years or older · Baseline for longitudinal studies, Low periodontal-disease prevalence Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | There were no statistically significant differences reported in the OHRQoL sum scores based on periodontal disease prevalence. | NR | Ungraded |
Caries-active status (presence of dental caries) vs Caries-free status Prevalence (detection frequency) of S. mutans in plaque · Systemically healthy individuals (children and adults, aged 40 months to 50 years) assessed for dental caries · Cross-sectional, Plaque sample Streptococcus mutans and Caries: A Systematic Review and Meta-Analysis. (2025) | OR 2.58 [1.65, 4.02] | 7 studies · 559 participants | Ungraded |
Hall technique vs Silver-modified atraumatic restorative treatment (SMART) Treatment success (caries lesion arrest or restoration survival) · Children (aged 3-11 y) with cavitated caries lesions in primary teeth · 12 months, 12-month follow-up Comparative success of minimally invasive treatments for cavitated caries in primary teeth: a network… (2025) | OR 4.36 [1.13, 16.77] | 43 studies | Moderate |
Intervention NR Inhibition of S. sobrinus growth and biofilm formation (incl. ftf/gtfB/gtfC expression) · In vitro Postbiotics and Dental Caries: A Systematic Review. (2025) | no estimate extracted | 1 study | Ungraded |
AI systems for caries detection/segmentation on dental X-ray images (predominantly convolutional neural networks; also ANNs, DNNs, DCNN, FCNN, SVMs, decision trees, random forests; e.g. EfficientNet, ResNet, AlexNet) vs Human dentists / trained dental professionals or traditional radiographic interpretation (reference standard / reference models) Sensitivity · Patients undergoing dental X-ray (radiographic) imaging for caries detection · Overall (all studies pooled) Accuracy of artificial intelligence in caries detection: a systematic review and meta-analysis. (2025) | OR 1.258 [0.493, 2.540] | 9 studies · 17190 participants | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 3: secondary caries · Continent: South America Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 7.62 [5.59, 10.38] | 2 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · HDI: Medium Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 12.93 [8.77, 19.05] | 2 studies | Ungraded |
Calcium vs Fluorine Immediate (24 h) resin-dentin bond strength (MPa) · permanent human teeth with artificial caries-affected dentin · 24 h, Etch-and-Rinse; chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD -0.628 [-8.504, 7.248] | 4 studies | Moderate |
Postbiotic toothpaste vs Fluoride toothpaste Increased salivary pH · Children aged 6-12 years · 4 weeks Postbiotics and Dental Caries: A Systematic Review. (2025) | Postbiotic toothpaste significantly increased salivary pH versus fluoride toothpaste in children (Basir 2022); postbiotics are also proposed to buffer acidic pH; no pooled estimate. | 1 study | Ungraded |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) Fracture of forearm · European-ancestry adults · Lifelong genetic liability, SVMR (IVW), total causal effect From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.921 [0.838, 1.012] | 490889 participants | Ungraded |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Probing Pocket Depth (PPD) · Individuals assessed for periodontal health (mainly children and adolescents, age >2 years) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | MD 0.88 [0.82, 0.95] | 3 studies · 340 participants | Low |
quantitative light-induced fluorescence (QLF) vs reference standard detection of occlusal caries · human primary or permanent teeth with dental caries lesions · all dentitions Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025) | Specificity 0.82 | 4 studies | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of fragility fractures · Females (all ages) · Long-term / lifetime fluoride exposure, Females: drinking-water fluoride 0.34 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 0.84 [0.67, 1.07] | NR | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Postmenopausal osteoporosis with pathological fracture · European GWAS participants · SVMR Maximum Likelihood From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.014 [0.872, 1.179] | 281786 participants | Ungraded |
Flavonoids (e.g., quercetin, proanthocyanidin) vs Calcium phosphate agent (e.g., CPP-ACP, Ca/P-PILP, niobophosphate) Immediate (24 h) resin-dentin bond strength (MPa) · Artificial caries-affected dentin (ACAD) in extracted permanent human teeth (in vitro) · 24 h (immediate), Self-Etch + chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD 3.065 [-4.318, 10.447] | 0 studies | Moderate |
Hydroxyapatite (e.g., nano-HAp) vs Calcium phosphate agent (e.g., CPP-ACP, Ca/P-PILP, niobophosphate) Immediate (24 h) resin-dentin bond strength (MPa) · Artificial caries-affected dentin (ACAD) in extracted permanent human teeth (in vitro) · 24 h (immediate), Self-Etch + chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD -4.455 [-8.857, -0.053] | 0 studies | Moderate |
Intervention NR Composite: Preference for replacement over repair - Scenario 5: open margin · Continent: Europe Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 4.04 [2.03, 8.06] | 6 studies | Ungraded |
Ion-releasing restorations (IRR): RMGIC, HVGIC, GIC, compomer/PMRC, giomer vs Composite resin (CR), including bulk-fill composite Retention · Children receiving dental restorations (aged 4-11 years; primary teeth; Class I/II/V cavities) · 1 to 2 years Clinical effectiveness of ion-releasing restorations compared to composite restorations in pediatric dental… (2025) | RR 1.02 [0.98, 1.07] | 5 studies · 555 participants | High |
Severe early childhood caries vs Caries-free controls Veillonella spp. relative abundance · Children under 6 years with severe early childhood caries and caries-free controls A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | Mean relative abundance (%) caries 5.25 (SD 6.65) vs control 15.22 (SD 9.48); P=0.033 | 1 study · 9 (caries only; control not reported in Table 3) participants | Ungraded |
Intervention NR Early childhood caries (ECC), prevalence · Study design: population-based Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 57 [44, 70] | 7 studies | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS, adjusted for periodontitis Postmenopausal osteoporosis with pathological fracture · European GWAS participants · MVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.281 [0.640, 2.565] | 281786 participants | Ungraded |
Ion-releasing restorations (IRR): RMGIC, HVGIC, GIC, compomer/PMRC, giomer vs Composite resin (CR), including bulk-fill composite Proper surface texture or luster · Children receiving dental restorations (aged 4-11 years; primary teeth; Class I/II/V cavities) · 1.5 to 2 years Clinical effectiveness of ion-releasing restorations compared to composite restorations in pediatric dental… (2025) | RR 1.00 [0.97, 1.02] | 4 studies · 720 participants | High |
Cavity liner (calcium hydroxide, glass-ionomer cement, resin-modified calcium silicate/TheraCal LC, hydraulic calcium silicate/MTA or Biodentine, flowable composite, or other liner material) vs No cavity liner or a different liner material Secondary caries prevention · Patients with deep caries lesions in mature or immature permanent (posterior) teeth, with no symptoms or reversible… · >=12 months Efficacy of different cavity liners compared to no cavity lining in managing deep caries in vital permanent… (2025) | No significant difference; ~100% prevention | 10 studies · 1009 participants | Low |
Obesity or overweight (higher BMI, mostly WHO BMI ≥25/≥30; 2 studies used waist circumference) vs Normal weight (not overweight or obese) Dental caries (study-defined binary; assessed by DMFT, number of dental caries, or dentist diagnosis) · Adults (≥18 years) · By sample size: n ≥ 5000 Multimorbidity patterns of dental caries and obesity/overweight among adults: a systematic review and… (2025) | OR 1.04 [0.92, 1.16] | NR | Ungraded |
Self-assembling/remineralizing peptide (e.g., P11-4, PAA-PASP) vs Fluoride agent (e.g., NaF/SDF/KF/CaF2) Immediate (24 h) resin-dentin bond strength (MPa) · Artificial caries-affected dentin (ACAD) in extracted permanent human teeth (in vitro) · 24 h (immediate), Etch-and-Rinse + biological ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD 14.098 [9.684, 18.512] | 2 studies | Moderate |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · Continent: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 18.59 [7.66, 45.10] | 11 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 4: marginal discoloration · Continent: South America Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 4.71 [2.97, 7.49] | 2 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Mean dmft (caries severity) · Children aged 0-5 years in North Africa · Overall Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | MEAN 2.95 [1.86, 4.67] | 13 studies | Ungraded |
Intervention NR Radiographic progression of proximal caries lesions · Caries depth: lesions up to DEJ (favored microinvasive; narrative, no numeric estimate) Microinvasive interventions in the management of proximal caries lesions in primary and permanent teeth-… (2025) | no estimate extracted | NR | Ungraded |
Electronic cigarette use vs Non-smokers IL-1β level · People who use electronic cigarettes · Overall The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.98 [-0.03, 1.99] | 11 studies | Ungraded |
Quantitative light-induced fluorescence (QLF) vs Reference standard (bitewing radiography, ADA classification, ICDAS II) Proximal caries detection: specificity · Patients (in vivo); permanent and primary teeth, proximal (approximal) surfaces · Overall (all dentition) Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025) | Specificity 0.82 | 4 studies | Ungraded |
AI algorithms (predominantly CNN/deep learning) as index test vs Dental expert / visual-tactile clinical assessment (reference standard) Positive likelihood ratio · Patients undergoing dental caries detection on dental images (teeth/surfaces across imaging modalities) · Cross-sectional diagnostic accuracy (index test vs reference standard), Overall (all imaging modalities pooled) Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | LR+ 10.443 [7.505, 14.531] | 20 studies · 29423 participants | Ungraded |