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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 Composite: 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 0.66 [0.49, 0.90] | NR | Ungraded |
Health expenditure per capita vs Not applicable OHRQoL sum score transformed to 0-100 · Community-dwelling adults aged 60 years or older · Baseline for longitudinal studies Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | There was no statistically significant difference in OHRQoL based on per capita expenditure on health care. | NR | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · Continent: South America Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.70 [0.60, 0.81] | 2 studies | Ungraded |
Very high Human Development Index (HDI >=0.800) vs High Human Development Index (HDI 0.700-0.799) 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), Human Development Index (ordinal logistic regression, adjusted) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | OR 1.82 [0.32, 10.47] | NR | Ungraded |
Ion-releasing restorations (IRR): RMGIC, HVGIC, GIC, compomer/PMRC, giomer vs Composite resin (CR), including bulk-fill composite Absence of wear · Children receiving dental restorations (aged 4-11 years; primary teeth; Class I/II/V cavities) · 2 years Clinical effectiveness of ion-releasing restorations compared to composite restorations in pediatric dental… (2025) | no estimate extracted | 1 study | Ungraded |
Country-level edentulism prevalence (Global Burden of Disease) vs Low vs high edentulism prevalence Oral health-related quality of life (OHRQoL sum score, transformed 0-100) · Community-dwelling elderly persons aged ≥60 years · Across edentulism 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 edentulism prevalence (Fig. 4c). | NR | Ungraded |
Dental treatments including dental care and services Aesthetics as a factor of choice · Potential patients in dental care, including parents or caregivers making treatment decisions; excludes patients with… Decision-making regarding dental treatments - What factors matter from patients' perspective? A systematic… (2025) | Number of articles identifying factor 53 | 53 studies | 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: not adjusted Multimorbidity patterns of dental caries and obesity/overweight among adults: a systematic review and… (2025) | OR 1.17 [1.04, 1.29] | NR | Ungraded |
Intervention NR Log diagnostic odds ratio · Imaging modality: Intraoral photographic images Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Log DOR 3.69 [2.80, 4.59] | 7 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 (all 3 included studies) Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025) | Specificity 0.74 | 3 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · Coverage: Not covering Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 3.85 [2.51, 5.93] | NR | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · Continent: Africa Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.86 [0.74, 1.00] | 2 studies | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Postmenopausal 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 1.214 [0.746, 1.977] | 281786 participants | Ungraded |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) Fracture of forearm · European-ancestry adults · Lifelong genetic liability, MVMR (IVW), adjusted for DMFS From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.995 [0.953, 1.039] | 490889 participants | Ungraded |
Human Development Index (HDI) vs Higher vs lower HDI categories Oral health-related quality of life (OHRQoL sum score, transformed 0-100) · Community-dwelling elderly persons aged ≥60 years · Medium HDI Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | MEAN 63.5 [54.3, 72.7] | 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: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 4.38 [2.91, 6.61] | 11 studies · 1917 participants | Ungraded |
Mineral trioxide aggregate (MTA) 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… · >=12 months Effectiveness of calcium hydroxide compared to hydraulic calcium silicate cements for direct pulp capping in… (2025) | OR 3.05 [1.70, 5.45] | 4 studies · 311 participants | Ungraded |
Partial pulpotomy vs Full (complete) pulpotomy Radiographic hard-tissue (dentine) barrier formation · Mature permanent (molar) teeth with deep caries and symptoms indicative of irreversible pulpitis (spontaneous pain) · 1 year The effectiveness of partial pulpotomy compared with full pulpotomy in managing deep caries in vital… (2025) | Ramani: radiographic hard-tissue barrier formation evident in 24.4% of full pulpotomy cases vs 11.6% of partial pulpotomy cases; difference not significant (p>.05). | 1 study · 106 participants | 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) | Specificity 0.74 | 3 studies | Ungraded |
Intervention NR Sensitivity · Imaging modality: CBCT Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Sensitivity 0.73 [0.68, 0.77] | 1 study | Ungraded |
Simple childhood caries prediction models with at least two predictors vs No competing model Dental caries discrimination (area under the curve) · Children and adolescents (≤18 years) · Validation assessment; prediction horizon not reported, Yaxuan (2023) Risk prediction models for dental caries in children and adolescents: a systematic review and meta-analysis. (2025) | AUC 0.931 [0.876, 0.967] | 1 study | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Femur fracture · European GWAS participants · SVMR Weighted Median From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.055 [0.979, 1.136] | 489106 participants | Ungraded |
Calcium phosphate agent (e.g., CPP-ACP, Ca/P-PILP, niobophosphate) 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 2.663 [-2.395, 7.722] | 4 studies | Moderate |
Intervention NR Composite: 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 3.71 [2.01, 6.82] | 11 studies | Ungraded |
HAART (highly active antiretroviral therapy, >=3 drugs) vs HIV-positive not receiving HAART (standard ART or HAART-naive) 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 2.02 [1.24, 2.80] | NR | Ungraded |
Quantitative light-induced fluorescence (QLF) vs Reference standard (histology, radiography) Proximal caries detection: specificity · 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) | Specificity 0.74 | 3 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 6: superficial discoloration · HDI: Medium Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.34 [0.24, 0.49] | 2 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · HDI: Low Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.75 [0.64, 0.87] | 2 studies | Ungraded |
Intervention NR Tooth loss and dental symptoms (cracked teeth, toothache) associated with e-cigarette use · Yang et al. [31] An Umbrella Review of E-Cigarettes' Impact on Oral Microbiota and Biofilm Buildup. (2025) | Qualitative (narrative synthesis) Increased tooth loss and dental symptoms with daily e-cigarette use | 1 study | Ungraded |
Flavonoids (e.g., quercetin, proanthocyanidin) vs HEMA/EGDMA-based desensitizer 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 2.705 [-5.654, 11.063] | 0 studies | Moderate |
Self-assembling/remineralizing peptide (e.g., P11-4, PAA-PASP) vs Hydroxyapatite (e.g., nano-HAp) 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 4.446 [-0.440, 9.332] | 0 studies | Moderate |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 6: corrosion · Continent: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.69 [1.12, 2.55] | 11 studies | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Femur fracture · European GWAS participants · SVMR Maximum Likelihood From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.044 [0.983, 1.109] | 489106 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: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 2.13 [1.40, 3.24] | 11 studies · 1917 participants | Ungraded |
E-cigarette aerosol / e-liquid exposure (flavored and unflavored; nicotine and non-nicotine) vs Unexposed controls / unflavored e-liquid / conventional cigarette smoke Enamel/dental hard-tissue changes and e-liquid cariogenic properties (demineralization, colour change, pH, sugar content, metals) · Oral bacteria (streptococci), dental hard tissue (enamel/dentin) and e-liquids studied in vitro/ex vivo (with a few… The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Narrative synthesis. In vitro studies showed e-liquids can be acidic (Fairchild 2021: 84% of vapes pH<5.5) and contain sugars (Fagan 2018 sucrose ~125 ug/ml; Kubica 2014 sucrose 0.76-72.93 ug/g), and e-cigarette… | NR | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · HDI: Low Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.12 [0.68, 1.86] | 2 studies | Ungraded |
Mesoporous silica (SiO2) 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 0.840 [-5.270, 6.950] | 1 study | Low |
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, Sensitivity (excluding high risk-of-bias studies): 1.8 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 0.95 [0.70, 1.29] | NR | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Postmenopausal 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 0.979 [0.826, 1.159] | 281786 participants | Ungraded |
Early childhood caries vs Caries-free controls Streptococcus mutans and Veillonella spp. levels · Young children with early childhood caries and caries-free controls A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | Veillonella spp. significantly greater in caries subjects, but detection unrelated to lesion development and unlikely to modify caries attack (qualitative) | 1 study · 9 participants | Ungraded |
Tooth brushing method (per source) vs Reference brushing method 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 1.435 [1.207, 2.915] | 1 study | Ungraded |
School-based supervised toothbrushing (STB) vs No intervention Dental caries increment, DMFT/dmft (whole-tooth level) · Children in school or kindergarten settings (aged 3-14 years) · 3-4 years follow-up The effectiveness of school-based supervised tooth brushing intervention for preventing dental caries: a… (2025) | SMD 0.05 [-0.27, 0.37] | 2 studies · 1239 participants | Ungraded |
Replacement of the defective restoration vs Repair of the defective restoration Amalgam: Preference for replacement over repair - Scenario 3: secondary caries · 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), Overall (all 21 countries pooled) Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 6.94 [5.53, 8.71] | 21 studies · 3680 participants | Ungraded |
Dental treatments including dental care and services Delay of dental care during the COVID-19 pandemic · Potential patients in dental care, including parents or caregivers making treatment decisions; excludes patients with… · US patients at COVID-19 onset (Papautsky et al. convenience sample, n=2570) Decision-making regarding dental treatments - What factors matter from patients' perspective? A systematic… (2025) | Proportion reporting delays 0.381 | 1 study · 2570 participants | Ungraded |
Caries-active status (presence of dental caries) vs Caries-free status Oral microbial community composition and diversity (other caries-associated taxa; alpha- and beta-diversity) · Systemically healthy individuals (children and adults, aged 40 months to 50 years) assessed for dental caries · Cross-sectional Streptococcus mutans and Caries: A Systematic Review and Meta-Analysis. (2025) | Narrative synthesis (no pooled estimate): no bacterial genus or species other than S. mutans was consistently (reported in more than 2 studies) associated with caries-active status (Table 3; 15 of 19 studies for… | NR | Ungraded |
Breastfeeding for 12-24 months vs Not breastfed at the same age Prevalence of early childhood caries · Children up to 71 months · 12-24 months Risk of Early Childhood Dental Caries Associated With Prolonged Breastfeeding: A Systematic Review and… (2025) | PR 3.32 [1.57, 5.07] | 2 studies | Low |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Lumbar spine and pelvis fracture · European GWAS participants · SVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.994 [0.729, 1.355] | 490700 participants | Ungraded |
Early childhood caries vs NA (within-white-spot-lesion correlation, not a caries vs caries-free comparison) Correlation of Veillonella spp. with acidogenic streptococci · Young children with early childhood caries and caries-free controls A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | R² 0.38 | 1 study · NA (white-spot correlation analytic sample not reported) participants | Ungraded |
Partial pulpotomy with immediate permanent restoration vs No comparator Clinical and radiographic success rate · Adults aged 18 years or older with mature permanent teeth and carious pulp exposure · Immediate restoration Partial pulpotomy for carious pulp exposure in adult mature permanent teeth: a systematic review and… (2025) | Success rate (%) 89.9 [78.5, 99.8] | NR | 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), Etch-and-Rinse + biological ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD -2.914 [-8.210, 2.382] | 2 studies | Moderate |