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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.
5,762 questions in 263 reviews · Dental caries
current versionsNo studies 321 · 5.6%Ungraded 4,450 · 77.2%Very low 455 · 7.9%Low 297 · 5.2%Moderate 200 · 3.5%High 39 · 0.7%
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 |