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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 |
|---|---|---|---|
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 |