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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 |
|---|---|---|---|
Intervention NR Amalgam: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · Coverage: Not covering Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 4.05 [2.84, 5.78] | NR | Ungraded |
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 Treatment failure · 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; 96.5% of treated teeth remained vital | 12 studies · 1184 participants | Very low |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 5: open margin · Continent: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 5.16 [3.50, 7.61] | 11 studies | Ungraded |
Hall technique vs Sodium fluoride varnish (NaF) 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 6.38 [1.41, 28.96] | 43 studies | Moderate |
Ion-releasing restorations (IRR): RMGIC, HVGIC, GIC, compomer/PMRC, giomer vs Composite resin (CR), including bulk-fill composite Absence of marginal discoloration · 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 1.00 [0.93, 1.08] | 6 studies · 872 participants | Moderate |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · Continent: South America Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 24.53 [6.02, 99.91] | 2 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 5: open margin · HDI: High Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 4.99 [3.14, 7.93] | 7 studies | Ungraded |
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 Postoperative hypersensitivity · Patients with deep caries lesions in mature or immature permanent (posterior) teeth, with no symptoms or reversible… · 7 days to 3 months Efficacy of different cavity liners compared to no cavity lining in managing deep caries in vital permanent… (2025) | No significant difference; minimal pain reported | 9 studies · 1000 participants | Very low |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 6: corrosion · HDI: High Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.91 [1.34, 2.73] | 7 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · Coverage: Covering cost of minimally invasive treatment Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 14.46 [7.75, 26.98] | NR | Ungraded |
Quantitative light-induced fluorescence (QLF) vs Reference standard (histology, radiography) Proximal caries detection: sensitivity · Extracted human teeth (in vitro); permanent teeth, proximal (approximal) surfaces · Overall (all studies permanent) Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025) | Sensitivity 0.83 | 3 studies | Ungraded |
Country-level income inequality (Gini index) vs Lower vs higher income inequality categories Oral health-related quality of life (OHRQoL sum score, transformed 0-100) · Community-dwelling elderly persons aged ≥60 years · Relative equality (Gini index 0.21 to 0.30) Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | MEAN 91.3 [90.0, 92.6] | NR | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS 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 1.097 [0.598, 2.011] | 376746 participants | Ungraded |
Electronic cigarette use vs Non-smokers IL-6 level · People who use electronic cigarettes · Saliva The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.78 [-0.56, 1.98] | 5 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · Coverage: Covering cost of minimally invasive treatment Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.90 [0.74, 1.10] | NR | Ungraded |
Partial pulpotomy with permanent restoration after 7-14 days vs No comparator Clinical and radiographic success rate · Adults aged 18 years or older with mature permanent teeth and carious pulp exposure · Permanent restoration after 7-14 days Partial pulpotomy for carious pulp exposure in adult mature permanent teeth: a systematic review and… (2025) | Success rate (%) 73.6 [66.5, 80.7] | NR | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 4: marginal discoloration · Coverage: Not covering Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 5.93 [3.86, 9.13] | NR | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability, adjusted for DMFS Lumbar spine and pelvis fracture · European GWAS participants · MVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.062 [0.991, 1.137] | 490700 participants | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · Continent: Africa Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.43 [0.36, 0.52] | 2 studies | Ungraded |
Higher per-capita expenditure on dental health care vs Lower per-capita expenditure on dental health care (USD bands: $0-50 / $51-100 / >$100) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), $0-50 per capita Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 3.06 [2.32, 3.79] | 14 studies | Ungraded |
Mesoporous silica (SiO2) 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 1.964 [-5.802, 9.730] | 0 studies | Moderate |
Composite resin restorations vs Amalgam restorations Restoration failure (replacement, tooth/restoration fracture, secondary caries, postoperative sensitivity, toothache) · Permanent posterior teeth (molars/premolars) receiving direct restoration · At least 12 months follow-up (included studies followed 24 to 144 months) Failure Risk of Composite Resin and Amalgam Restorations: A Systematic Review and Meta-Analysis. (2025) | RR 0.96 [0.68, 1.34] | 13 studies | Ungraded |
Fluoride mouthrinse (0.05-0.32% sodium fluoride or amine fluoride) added to daily fluoride toothpaste vs Control: fluoride toothpaste alone, placebo mouthrinse + toothpaste, or non-fluoride (chlorhexidine) mouthrinse + toothpaste Incidence of initial caries around brackets, aesthetic-zone teeth only · Children, adolescents and adults undergoing fixed (multi-bracket) orthodontic treatment · At debonding (Gorelick index), Aesthetic zone (central and lateral incisors, canines) Fluoride mouthrinses for prevention of initial caries in orthodontic patients - a systematic review and… (2025) | In two studies, a significant reduction of the incidence of initial caries around orthodontic brackets was reported in the FMR group when only teeth in the 'aesthetic zone' (central and lateral incisors, canines) were… | 2 studies | Ungraded |
Epilepsy (as exposure/condition) vs Healthy participants without epilepsy (control group) dmft (primary teeth) · Children and adolescents with epilepsy · Children/adolescents Evaluating the DMFT and dmft indices in people with epilepsy: A systematic review and meta-analysis. (2025) | SMD 0.132 [-0.220, 0.484] | NR | Ungraded |
Higher parental education (tertiary) vs Lower parental education (reference) Early childhood caries (ECC) · Children aged 0-5 years in North Africa · Paternal tertiary education [Kabil] Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 0.381 [0.16, 0.91] | 1 study | Ungraded |
Secondary (passive/secondhand) smoking exposure during childhood vs No secondary smoking exposure Caries prevalence (early childhood caries) · Preschool children aged <=71 months (caries outcome assessed at 3-6 years) · Caries prevalence at 3-6 years, Overall Secondary Smoking and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2025) | OR 1.77 [1.57, 2.01] | 11 studies · 14,794 participants | Very low |
Partial pulpotomy with tri-calcium silicate material (MTA or Biodentine) vs No comparator Clinical and radiographic success rate · Adults aged 18 years or older with mature permanent teeth and carious pulp exposure · At least 1 year, MTA or Biodentine Partial pulpotomy for carious pulp exposure in adult mature permanent teeth: a systematic review and… (2025) | Success rate (%) 86.8 [83.78, 89.82] | NR | Ungraded |
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 |
All dental health care expenditure strata vs No comparator (single-group pooled mean) DMFT caries experience · 12-year-old children in European countries · 2011-2022, Overall Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | Mean DMFT 2.10 [1.61, 2.59] | 32 studies | Ungraded |
Daily tooth brushing vs Reference (no/less brushing) Early childhood caries (ECC) · Children aged 0-5 years in North Africa · Twice daily Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 0.033 [0.004, 0.276] | 1 study | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Lumbar spine bone mineral density (BMD) · General population (both sexes, all ages) · Long-term / lifetime fluoride exposure, Sensitivity (excluding high risk-of-bias studies): 1.27 to 2.27 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | MD 0.05 [0.01, 0.10] | NR | Ungraded |
Higher national income (GNI per capita) vs Lower national income (GNI categories: middle <=$15,000 / high $15,001-25,000 / very high >$25,000) Odds of higher caries (DMFT) category · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), Higher vs lower income (ordinal logistic regression, adjusted) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | OR 0.10 [0.03, 0.37] | NR | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · Coverage: Covering cost of minimally invasive treatment Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.33 [0.22, 0.50] | NR | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 6: superficial discoloration · HDI: Low Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.22 [0.08, 0.59] | 2 studies | 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), Overall (all 21 countries pooled) Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 2.43 [1.87, 3.16] | 21 studies · 3680 participants | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · Coverage: Covering cost of minimally invasive treatment Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.70 [0.60, 0.82] | NR | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Osteoporosis with pathological fracture · European GWAS participants · SVMR Weighted Median From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.181 [0.748, 1.866] | 376746 participants | 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) Oral health attitude · Children and adolescents aged 5-18 years · Post-intervention (follow-up immediately after to 6 months, varies by study), Overall Health promotion theory-based educational interventions for improving oral health in children and… (2025) | SMD 9.32 [7.08, 11.55] | 3 studies · 2370 participants | Low |
Intervention NR Composite: Preference for replacement over repair - Scenario 6: superficial discoloration · Coverage: Not covering Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.29 [0.18, 0.45] | NR | Ungraded |
Sugar consumption (higher sugar intake) vs No sugar consumption (lower/no intake) Early childhood caries (ECC) · Children under 6 years of age · Outcome (ECC) assessed from 9 months to 5 years of age, Overall (all 9 meta-analyzed studies pooled) Sugar consumption and early childhood caries: a systematic review and meta-analysis of cohort studies. (2025) | OR 1.59 [1.50, 1.68] | 9 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 · Permanent dentition Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025) | Specificity 0.81 | 3 studies | Ungraded |
Ion-releasing restorations (IRR): RMGIC, HVGIC, GIC, compomer/PMRC, giomer vs Composite resin (CR), including bulk-fill composite Integrity of contact point · Children receiving dental restorations (aged 4-11 years; primary teeth; Class I/II/V cavities) · 2 to 5 years Clinical effectiveness of ion-releasing restorations compared to composite restorations in pediatric dental… (2025) | RR 0.99 [0.91, 1.08] | 3 studies · 229 participants | High |
HIV-infected children on antiretroviral therapy (HI) vs HIV-exposed but uninfected children (HEU) 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 3.73 [1.88, 7.40] | NR | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 6: superficial discoloration · Continent: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.30 [0.18, 0.50] | 11 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: Europe Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 2.61 [1.54, 4.42] | 6 studies · 1075 participants | Ungraded |
Western/Northern Europe (UN M49 region) vs Eastern/Southern Europe (UN M49 geographical categorization) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), North Europe Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 1.34 [0.62, 2.06] | 8 studies | Ungraded |
HIV infection with antiretroviral therapy (ART/HAART) vs HIV-negative individuals Dental caries severity (dmfs index, primary dentition) · Children and adolescents under 18 years with HIV · Not specified (case-control), Case-control studies; dmfs index Association between antiretroviral therapy and dental caries in children and adolescents with HIV: a… (2025) | MD 5.15 [2.20, 8.11] | 2 studies · 185 participants | 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) Diagnostic accuracy (prevalence of accuracy) · Patients undergoing dental X-ray (radiographic) imaging for caries detection · Digital bitewing X-rays (Fig 4a) Accuracy of artificial intelligence in caries detection: a systematic review and meta-analysis. (2025) | ~80 | 1 study | Ungraded |
All GNI strata vs No comparator (single-group pooled mean) DMFT caries experience · 12-year-old children in European countries · 2011-2022, Overall Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | Mean DMFT 2.10 [1.63, 2.57] | 34 studies | Ungraded |
All M49 regions vs No comparator (single-group pooled mean) DMFT caries experience · 12-year-old children in European countries · 2011-2022, Overall Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | Mean DMFT 2.10 [1.63, 2.57] | 34 studies | Ungraded |