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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 |
|---|---|---|---|
Full pulpotomy vs Partial pulpotomy Clinical and radiographic success rate · Adults aged 18 years or older with mature permanent teeth and carious pulp exposure · 1 year, Irreversible pulpitis Partial pulpotomy for carious pulp exposure in adult mature permanent teeth: a systematic review and… (2025) | Log odds ratio (LogOR) -0.77 [-1.62, 0.09] | 3 studies · 204 participants | Ungraded |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Gingival Index (GI) · 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 0.15 [0.11, 0.19] | 4 studies · 488 participants | Low |
Calcium vs Control 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 -0.508 [-8.207, 7.191] | 3 studies | Very low |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability 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 1.003 [0.874, 1.151] | 376746 participants | Ungraded |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) Osteoporosis · European-ancestry adults · Lifelong genetic liability, MVMR (IVW), adjusted for periodontitis From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.165 [1.020, 1.331] | 483725 participants | Ungraded |
Anticaries vaccine or antibody (DNA, recombinant protein, nanoparticle-adjuvanted, live-vector, plant-based, or passive IgY immunization) targeting S. mutans vs Control (unvaccinated / empty vector / PBS / placebo animals) Streptococcus mutans colonization reduction (narrative; no CFU data reported) · Animal caries models (mice, rats, hamsters) challenged/colonized with Streptococcus mutans; one transgenic-plant… Assessing the Efficacy and Immunogenicity of Anticaries Vaccine-A Systematic Review and Meta-Analysis. (2025) | no estimate extracted | NR | Ungraded |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) Forearm bone mineral density (FA-BMD) · European-ancestry adults · Lifelong genetic liability, SVMR and MVMR (IVW) From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | No causal effect of oral diseases on FA-BMD was found (SVMR and MVMR); no numeric estimate reported in text (see Fig. 3). | 8143 participants | Ungraded |
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 confounder adjustment: adjusted Multimorbidity patterns of dental caries and obesity/overweight among adults: a systematic review and… (2025) | OR 1.00 [0.89, 1.12] | NR | Ungraded |
Ion-releasing restorations (IRR): RMGIC, HVGIC, GIC, compomer/PMRC, giomer vs Composite resin (CR), including bulk-fill composite Adequate marginal adaptation · 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 [0.96, 1.08] | 5 studies · 335 participants | High |
Hall technique vs Sealing 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 13.93 [1.34, 144.52] | 43 studies | Moderate |
Mineral trioxide aggregate (MTA) vs Calcium hydroxide (CaOH) Postoperative pain (patient-reported) · Vital permanent teeth (mature or immature) with deep or extremely deep caries and asymptomatic pulp or reversible… · 6 hours to 7 days Effectiveness of calcium hydroxide compared to hydraulic calcium silicate cements for direct pulp capping in… (2025) | Two studies assessed postoperative pain; no meta-analysis was performed due to methodological heterogeneity. Suhag 2019: significantly higher pain in CaOH than MTA at 18 h (CaOH 18.5 +/- 20.8 mm vs MTA 6.3 +/- 9.5 mm,… | 2 studies | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of femoral fractures · General population (both sexes, all ages) · Long-term / lifetime fluoride exposure, Drinking-water fluoride 1.8 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 1.06 [0.67, 1.69] | NR | Ungraded |
E-cigarette use (ENDS / vaping) vs Non-smokers Interleukin-6 (IL-6) · Humans who use e-cigarettes (mostly adults, often with periodontal disease) assessed for oral proinflammatory markers · Cross-sectional (single time point) for most; a few 6-month prospective, Overall (saliva + GCF) The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.83 [-0.16, 1.79] | 6 studies | 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) Specificity · 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) | Proportion (weighted mean specificity, %) 87.90 | 7 studies | Ungraded |
Dental treatments, care, and services (the decision context) vs None (no comparator defined) Dental fear (fear of treatment) as a factor of choice · (Potential) patients with freedom of choice regarding dental treatments, including parents and caregivers deciding for… Decision-making regarding dental treatments - What factors matter from patients' perspective? A systematic… (2025) | 'Fear' (of treatment; synonyms e.g., 'fear of needles') identified in N=64 articles (code frequency n=73), the second most frequent factor; frequently reported in India (42%), Saudi Arabia (39%) and Brazil (36%), but… | 64 studies | Ungraded |
Higher drinking-water fluoride concentration vs Null/reference drinking-water fluoride exposure Spine bone mineral density · Females · Females, low-to-moderate risk-of-bias studies: above 2.35 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | MD 0.07 [0.11, 0.24] | NR | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · HDI: Medium Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.40 [0.08, 2.03] | 2 studies | Ungraded |
Children with dental caries vs Children without dental caries (caries-free) Mean corpuscular volume (MCV) · Children and adolescents (0-18 years; most included reviews focused on <6 years) Association Between Iron Deficiency Anemia and Dental Caries in Children: A Systematic Umbrella Meta-Analysis. (2025) | MD -1.96 [-4.02, 0.10] | 3 studies | Very low |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of fragility fractures · Males · Long-term / lifetime fluoride exposure, Males: drinking-water fluoride 1.8 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 0.87 [0.48, 1.58] | 7 studies | Ungraded |
Replacement of the defective restoration vs Repair of the defective restoration Amalgam: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · Dentists managing a defective direct amalgam restoration (posterior occlusal Class I; standardized vignette of a… · Not applicable (single time-point survey, June to October 2023), Continent: South America Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 6.20 [4.66, 8.25] | 2 studies · 349 participants | Ungraded |
Replacement of the defective restoration vs Repair of the defective restoration Composite: Preference for replacement over repair - Scenario 3: secondary caries · Dentists managing a defective direct resin composite restoration (posterior occlusal Class I; standardized vignette of… · Not applicable (single time-point survey, June to October 2023), Continent: Africa Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 4.62 [3.64, 5.86] | 2 studies · 339 participants | Ungraded |
Electronic cigarette use vs Non-smokers IL-6 level · People who use electronic cigarettes · GCF The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 1.43 [0.76, 2.10] | 1 study | Ungraded |
Quantitative light-induced fluorescence (QLF) vs Reference standard (histology; some ICDAS/radiography) Occlusal caries detection: sensitivity · Extracted human teeth (in vitro); permanent and primary teeth, occlusal surfaces · Overall (all dentition) Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025) | Sensitivity 0.83 | 5 studies | Ungraded |
Self-assembling/remineralizing peptide (e.g., P11-4, PAA-PASP) 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 -0.009 [-4.076, 4.058] | 1 study | Low |
HIV infection with antiretroviral therapy (ART/HAART) vs HIV-negative individuals Dental caries (presence/absence) · Children and adolescents under 18 years with HIV · Not specified (cross-sectional), Cross-sectional studies Association between antiretroviral therapy and dental caries in children and adolescents with HIV: a… (2025) | OR 2.04 [1.21, 3.42] | 6 studies · 2206 participants | Very low |
Intervention NR Composite: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · HDI: Very high Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.70 [0.49, 1.00] | 10 studies | Ungraded |
Dental caries (ECC/severe ECC) as exposure/grouping vs Caries-free controls Relative abundance of Streptococcus mutans · Individuals assessed for dental caries, predominantly children with early childhood caries (ECC) or severe ECC (age… A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | Reported in 2 studies without pooling: Agnello 2017 median S. mutans relative abundance 0.73% (0.02-22.9) in caries vs 0.15% (0.006-10.4) in controls; Chalmers 2015 Streptococcus 35.63+/-17.04 (caries) vs 32.11+/-18.91… | 1 study · 50 participants | Ungraded |
Hall technique vs Placebo Treatment success (caries lesion arrest or restoration survival) · Children (aged 3-11 y) with cavitated caries lesions in primary teeth · 6 months, 6-month follow-up Comparative success of minimally invasive treatments for cavitated caries in primary teeth: a network… (2025) | OR 163.59 [10.15, 2636.00] | 44 studies | Moderate |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Country: Tunisia Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 38 [24, 51] | 4 studies | Ungraded |
Theory-based oral health education/promotion interventions (HBM, TPB, SCT, HAPA, TTM, PMT, SOC, PRECEDE-PROCEED, MI) vs Control (waitlist, routine/standard oral health education, or minimal intervention) Self-efficacy related to oral health · Children and adolescents aged 5-18 years · Post-intervention (follow-up 4 weeks to 12 months, varies by study), Overall Health promotion theory-based educational interventions for improving oral health in children and… (2025) | SMD 1.49 [0.99, 2.00] | 10 studies · 4513 participants | Low |
HEMA/EGDMA-based desensitizer 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), Self-Etch + chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD 1.899 [-3.210, 7.009] | 1 study | Low |
Calcium phosphate agent (e.g., CPP-ACP, Ca/P-PILP, niobophosphate) 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), Self-Etch + chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD 2.140 [-1.506, 5.787] | 1 study | Moderate |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of fragility fractures · General population (both sexes, all ages) · Long-term / lifetime fluoride exposure, Drinking-water fluoride up to 0.9 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 0.93 [0.84, 1.02] | NR | Ungraded |
Self-assembling/remineralizing peptide (e.g., P11-4, PAA-PASP) vs Calcium-based agent 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 2.654 [-3.216, 8.524] | 0 studies | Moderate |
Hall technique vs Atraumatic restorative treatment (ART) Treatment success (caries lesion arrest or restoration survival) · Children (aged 3-11 y) with cavitated caries lesions in primary teeth · 6 months, 6-month follow-up Comparative success of minimally invasive treatments for cavitated caries in primary teeth: a network… (2025) | OR 10.11 [3.03, 33.71] | 44 studies | Moderate |
Hall technique vs Conventional restoration Treatment success (caries lesion arrest or restoration survival) · Children (aged 3-11 y) with cavitated caries lesions in primary teeth · 12-24 months, 12-24-month follow-up Comparative success of minimally invasive treatments for cavitated caries in primary teeth: a network… (2025) | OR 4.17 [1.44, 12.10] | 21 studies | Moderate |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · Coverage: Not covering Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.67 [1.20, 2.30] | NR | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · Continent: Europe Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.59 [0.38, 0.90] | 6 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 6: corrosion · HDI: Medium Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.39 [0.41, 4.68] | 2 studies | Ungraded |
Electronic cigarette use vs Non-smokers TNF-α level · People who use electronic cigarettes · GCF The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 2.19 [1.53, 2.84] | 2 studies | Ungraded |
Self-assembling/remineralizing peptide (e.g., P11-4, PAA-PASP) vs Calcium-based agent 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 4.044 [-4.923, 3.011] | 0 studies | Low |
Dental treatments, care, and services (the decision context) vs None (no comparator defined) Aesthetics as a factor of choice · (Potential) patients with freedom of choice regarding dental treatments, including parents and caregivers deciding for… Decision-making regarding dental treatments - What factors matter from patients' perspective? A systematic… (2025) | 'Aesthetics' (synonyms e.g., 'cosmetic') identified in N=53 articles (code frequency n=64); mentioned most in Brazil (57%) and Saudi Arabia (30%), less often in India (11%) and Turkey (9%). | 53 studies | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Forearm fracture · European GWAS participants · SVMR Weighted Median From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.992 [0.945, 1.042] | 490889 participants | Ungraded |
Intervention NR Amalgam: 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 4.79 [2.98, 7.69] | 6 studies | Ungraded |
E-cigarette use (ENDS / vaping) vs Non-smokers Dry mouth (xerostomia) · Humans who use e-cigarettes (adolescents to adults) assessed for dental caries · Cross-sectional to 12 months The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Narrative synthesis. E-cigarette users reported dry mouth more frequently than non-smokers: Chaffee 2021 dry mouth 12% (OR 1.4); Alhajj 2022 dry mouth 33.3% in e-cigarette users vs 23.4% in controls. Not pooled. | 2 studies | Ungraded |
Country-level periodontal disease prevalence (Global Burden of Disease) vs Low vs high periodontal disease prevalence Oral health-related quality of life (OHRQoL sum score, transformed 0-100) · Community-dwelling elderly persons aged ≥60 years · Across periodontal disease prevalence categories Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | No statistically significant difference in OHRQoL based on periodontal disease prevalence (Fig. 4b). | NR | Ungraded |
Country-level income (World Bank income classification) vs Higher- vs lower-income country categories Oral health-related quality of life (OHRQoL sum score, transformed 0-100) · Community-dwelling elderly persons aged ≥60 years · High-middle to high income Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | MEAN 77.9 [70.2, 85.6] | NR | Ungraded |
Hydraulic calcium silicate cements (HCSC; MTA or Biodentine) vs Calcium hydroxide (CaOH) Clinical and radiographic success · Vital permanent teeth (mature or immature) with deep or extremely deep caries and asymptomatic pulp or reversible… · 36 months, 36-month follow-up Effectiveness of calcium hydroxide compared to hydraulic calcium silicate cements for direct pulp capping in… (2025) | OR 2.34 [1.43, 3.84] | 2 studies · 379 participants | Ungraded |
HIV infection with antiretroviral therapy (ART/HAART) vs HIV-negative individuals Dental caries severity (dmft index, primary dentition) · Children and adolescents under 18 years with HIV · Not specified (cross-sectional), Cross-sectional studies; dmft index Association between antiretroviral therapy and dental caries in children and adolescents with HIV: a… (2025) | MD 0.92 [-0.09, 1.93] | 5 studies · 1502 participants | Very low |
Replacement of the defective restoration vs Repair of the defective restoration Composite: Preference for replacement over repair - Scenario 4: marginal discoloration · Dentists managing a defective direct resin composite restoration (posterior occlusal Class I; standardized vignette of… · Not applicable (single time-point survey, June to October 2023), Overall (all 21 countries pooled) Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.97 [1.55, 2.49] | 21 studies · 3680 participants | Ungraded |