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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 |
|---|---|---|---|
Dental caries (presence or experience) vs Adolescents without dental caries Negative oral-health impact on daily performance (OIDP or Child-OIDP) · Adolescents aged 10 to 19 years · Cross-sectional (concurrent exposure and outcome); oral impacts recalled over the prior 6 months, Overall (all meta-analyzed studies pooled; both instruments and both caries definitions) Impact of dental caries on the quality of life of adolescents: A systematic review and meta-analysis. (2025) | PR 1.52 [1.15, 2.01] | 9 studies | 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), West Europe Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 0.88 [0.54, 1.22] | 5 studies | Ungraded |
Intervention NR Amalgam: 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 1.76 [1.38, 2.24] | NR | 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 (binary; DMFT-based or dentist-diagnosed caries present) · Adults (≥18 years) · By BMI classification: overweight (vs study-defined non-overweight: normal or low weight) Multimorbidity patterns of dental caries and obesity/overweight among adults: a systematic review and… (2025) | OR 0.99 [0.98, 1.00] | NR | Ungraded |
Resin infiltration vs Non-invasive measures (fluoride varnish/toothpaste, flossing, oral hygiene instruction, sham/standard of care) Radiographic progression of proximal caries lesions · Children and adults with non-cavitated proximal (interproximal) caries lesions in primary and/or permanent teeth (ages… · Final follow-up (1 to 7 years across trials), Resin infiltration vs non-invasive (Fig. 5, subgroup 2.1.1) Microinvasive interventions in the management of proximal caries lesions in primary and permanent teeth-… (2025) | OR 0.23 [0.15, 0.35] | 10 studies · 459 participants | Ungraded |
Partial pulpotomy with one-unit longer follow-up vs Partial pulpotomy with one-unit shorter follow-up Clinical and radiographic success rate · Adults aged 18 years or older with mature permanent teeth and carious pulp exposure · Per unit increase in follow-up time, Sensitivity analysis excluding studies with high risk of bias Partial pulpotomy for carious pulp exposure in adult mature permanent teeth: a systematic review and… (2025) | Meta-regression coefficient -0.36 | NR | Ungraded |
Intervention NR Sensitivity · Imaging modality: Intraoral photographic images Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Sensitivity 0.80 [0.69, 0.90] | 7 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 4: marginal discoloration · HDI: Medium Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 2.01 [0.98, 4.09] | 2 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · Coverage: Not covering Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 18.78 [8.63, 40.89] | NR | Ungraded |
Intervention NR Amalgam: 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 34.41 [16.26, 72.86] | NR | Ungraded |
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 1.48 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 1.00 [0.82, 1.21] | NR | Ungraded |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) 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 1.055 [0.984, 1.130] | 490700 participants | Ungraded |
Calcium phosphate vs Control Immediate (24 h) resin-dentin bond strength (MPa) · permanent human teeth with artificial caries-affected dentin · 24 h, Etch-and-Rinse; biological ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD -21.209 [-25.954, -16.463] | 2 studies | Moderate |
Intervention NR Amalgam: 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 1.57 [1.31, 1.87] | 2 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 5: open margin · Continent: Africa Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 7.59 [3.13, 18.38] | 2 studies | Ungraded |
Flavonoids (e.g., quercetin, proanthocyanidin) 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 + biological ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD 8.438 [2.289, 14.587] | 1 study | Moderate |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · HDI: Low Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.47 [0.87, 2.48] | 2 studies | Ungraded |
HIV infection with antiretroviral therapy (ART/HAART) vs HIV-negative individuals Dental caries severity (DMFT index, permanent dentition) · Children and adolescents under 18 years with HIV · Not specified (case-control), Case-control studies; DMFT index Association between antiretroviral therapy and dental caries in children and adolescents with HIV: a… (2025) | MD 0.85 [0.04, 1.66] | 2 studies · 204 participants | Very low |
Lower unemployment rate vs Higher unemployment rate (low <=5% / medium >5-10% / high >10%) 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), Unemployment rate (ordinal logistic regression, adjusted) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | OR 0.99 [0.44, 2.23] | NR | 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 (cross-sectional), Cross-sectional studies; dmfs index Association between antiretroviral therapy and dental caries in children and adolescents with HIV: a… (2025) | MD 4.00 [2.64, 5.36] | 1 study · 564 participants | Ungraded |
Restricted partial pulpotomy (pulp removal 2-3 mm from exposure site only) vs Extended partial pulpotomy (pulp removal 2-3 mm from entire pulp chamber with complete deroofing) Clinical and radiographic success rate · Adults (18-45 y) with mature permanent molars, carious exposure and symptomatic irreversible pulpitis · 1 year, Lateral extent of pulp amputation Partial pulpotomy for carious pulp exposure in adult mature permanent teeth: a systematic review and… (2025) | Success rate (%) 97.6 vs 97.5 | 1 study · 96 participants | Ungraded |
Simplified caries prediction models (>=2 predictors; microbiome-primary studies excluded), but some pooled models include microbe predictors (Yaxuan 2023: S. mutans; Kim 2018: biofilm acidogenicity/saliva) vs None (no competing model) Model discrimination (area under the ROC curve, AUC) · Children and adolescents aged 1-18 years · Prediction of future/undiagnosed caries; cohort follow-up 3 months-10 years, Overall (6 validated models pooled) Risk prediction models for dental caries in children and adolescents: a systematic review and meta-analysis. (2025) | AUC 0.79 [0.73, 0.84] | 6 studies | Ungraded |
Intervention NR Composite: 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 8.17 [2.20, 30.35] | 2 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 4: marginal discoloration · Continent: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 2.14 [1.47, 3.10] | 11 studies | Ungraded |
HEMA/EGDMA-based desensitizer 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 3.023 [-3.815, 9.861] | 0 studies | Moderate |
Electronic cigarette use vs Non-smokers IL-6 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 0.83 [-0.16, 1.79] | 6 studies | Ungraded |
Epilepsy (as exposure/condition) vs Healthy participants without epilepsy (control group) dmft (decayed, missing, filled primary teeth) · People with epilepsy (children, adolescents, and adults) Evaluating the DMFT and dmft indices in people with epilepsy: A systematic review and meta-analysis. (2025) | SMD 0.132 [-0.22, 0.484] | 5 studies | High |
Intervention NR Composite: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · Continent: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.38 [0.26, 0.56] | 11 studies | Ungraded |
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: Sudan Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 63 [52, 74] | 3 studies | Ungraded |
quantitative light-induced fluorescence (QLF) vs reference standard detection of proximal caries · human primary or permanent teeth with dental caries lesions · permanent dentition Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025) | Sensitivity 0.83 | 3 studies | Ungraded |
E-cigarette use (ENDS / vaping) vs Non-smokers Tumour necrosis factor-alpha (TNF-α) · 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 0.66 [-0.16, 1.43] | 7 studies | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability, adjusted for DMFS 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 1.002 [0.867, 1.158] | 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 knowledge · Children and adolescents aged 5-18 years · Post-intervention (follow-up immediately after to 24 months, varies by study), Overall Health promotion theory-based educational interventions for improving oral health in children and… (2025) | SMD 1.09 [0.80, 1.39] | 7 studies · 10904 participants | Low |
Intervention NR Composite: Preference for replacement over repair - Scenario 4: marginal discoloration · Coverage: Covering cost of minimally invasive treatment Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 2.00 [1.25, 3.20] | NR | Ungraded |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) 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 |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Sample size >500 Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 65 [55, 75] | 9 studies | Ungraded |
AI algorithms (predominantly CNN/deep learning) as index test vs Dental expert / visual-tactile clinical assessment (reference standard) Area under the summary ROC curve · 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) | AUC 0.86 | 20 studies · 29423 participants | 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 |
Western/Northern Europe (UN M49 region) vs Eastern/Southern Europe (UN M49 geographical categorization) 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), Geographical location (ordinal logistic regression, adjusted) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | OR 0.57 [0.24, 1.35] | NR | 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: Africa Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 4.86 [3.79, 6.23] | 2 studies · 339 participants | Ungraded |
Electronic cigarette use vs Non-smokers Combined salivary IL-1β, IL-6, IL-8, and TNF-α levels · 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 0.21 [-0.36, 0.77] | 4 studies | Ungraded |
Intervention NR Specificity · Imaging modality: Panoramic radiographs Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Specificity 0.97 [0.96, 0.98] | 8 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), Continent: Europe Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 3.07 [2.41, 3.89] | 6 studies · 1075 participants | Ungraded |
Unsupervised tooth brushing vs Supervised brushing Early childhood caries (ECC) · Children aged 0-5 years in North Africa Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 1.385 [0.809, 1.369] | 1 study | Ungraded |
Fluoride agent (e.g., NaF/SDF/KF/CaF2) 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 -0.120 [-3.783, 3.544] | 8 studies | Very low |
Intervention NR Composite: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · HDI: Low Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 8.50 [6.23, 11.61] | 2 studies | Ungraded |
Quantitative light-induced fluorescence (QLF) vs Reference standard (ICDAS II visual examination, ADA classification, bitewing radiography) Occlusal caries detection: sensitivity · Patients (in vivo); permanent and primary teeth, occlusal surfaces · Permanent dentition Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025) | Sensitivity 0.86 | 3 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · Continent: Africa Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 14.98 [4.84, 46.32] | 2 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · HDI: High Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.79 [0.70, 0.88] | 7 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) Diagnostic accuracy (prevalence of accuracy) · Patients undergoing dental X-ray (radiographic) imaging for caries detection · Periapical X-rays (Fig 4c) Accuracy of artificial intelligence in caries detection: a systematic review and meta-analysis. (2025) | ~76 | NR | Ungraded |