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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 |
|---|---|---|---|
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): 0.60 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | MD 0.06 [-0.02, 0.13] | NR | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · HDI: Very high Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.79 [0.53, 1.18] | 10 studies | Ungraded |
Country-level income (World Bank income classification) vs Higher- vs lower-income country categories Oral health-related quality of life (OHRQoL sum score, transformed 0-100) · Community-dwelling elderly persons aged ≥60 years · Low-middle income Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | MEAN 66.9 [56.7, 77.0] | NR | 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 + biological ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD 4.197 [1.080, 7.314] | 4 studies | Moderate |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability, adjusted for DMFS Lumbar spine bone mineral density · European GWAS participants · MVMR IVW From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | BETA 0.047 [-0.002, 0.096] | 28498 participants | 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 (cross-sectional), Cross-sectional studies; DMFT index Association between antiretroviral therapy and dental caries in children and adolescents with HIV: a… (2025) | MD 0.60 [-0.53, 1.72] | 4 studies · 1390 participants | Very low |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) Osteoporosis with pathological fracture · 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 1.261 [0.918, 1.732] | 376746 participants | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 5: open margin · HDI: Very high Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 5.19 [3.39, 7.94] | 10 studies | Ungraded |
Intervention NR Postoperative hypersensitivity · Potassium nitrate liner vs polycarboxylate cement (Hodosh et al.) Efficacy of different cavity liners compared to no cavity lining in managing deep caries in vital permanent… (2025) | Postoperative hypersensitivity reduction Significant reduction with potassium nitrate; p<0.05 (p<0.01 in subgroup section) | 1 study | Ungraded |
Intervention NR Amalgam: 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 1.50 [1.08, 2.08] | 11 studies | Ungraded |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) Fracture of lumbar spine and pelvis · 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 1.060 [0.989, 1.135] | 490700 participants | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS, adjusted for periodontitis Osteoporosis · European GWAS participants · MVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.343 [1.015, 1.778] | 483725 participants | Ungraded |
Epilepsy (as exposure/condition) vs Healthy participants without epilepsy (control group) DMFT (decayed, missing, filled permanent 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 0.403 [0.057, 0.749] | 7 studies | High |
Intervention NR Composite: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · Continent: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.78 [0.56, 1.10] | 11 studies | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Lumbar spine bone mineral density (BMD) · Females (all ages) · Long-term / lifetime fluoride exposure, Females, low-to-moderate risk-of-bias studies: 0.7-2.35 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | MD 0.06 [-0.01, 0.12] | NR | Ungraded |
E-cigarette use (electronic nicotine delivery systems / vaping) vs Non-smokers (never-smokers) Peri-implant clinical and radiographic parameters (plaque index, probing depth, bone loss, pro-inflammatory profile) · Adult e-cigarette (ENDS) users with dental implants (incl. male implant-supported prosthesis patients) · Implant/peri-implant populations: Vamos (implant patients), Youssef (male implant patients only), Yang (broad SR incl. peri-implant) An Umbrella Review of E-Cigarettes' Impact on Oral Microbiota and Biofilm Buildup. (2025) | Narrative synthesis: e-cigarette users with dental implants showed a higher peri-implant plaque index and worse clinico-radiographic and immunological peri-implant parameters than non-smokers (worse than non-smokers… | 3 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · HDI: Very high Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.40 [0.27, 0.59] | 10 studies | Ungraded |
Country-level unemployment rate vs Higher vs lower unemployment-rate categories Oral health-related quality of life (OHRQoL sum score, transformed 0-100) · Community-dwelling elderly persons aged ≥60 years · Across unemployment-rate 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 unemployment rate (Fig. 2c). | NR | Ungraded |
Replacement of the defective restoration vs Repair of the defective restoration Composite: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · 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 0.72 [0.58, 0.89] | 21 studies · 3680 participants | Ungraded |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Clinical Attachment Level (CAL) · Individuals assessed for periodontal health (mainly children and adolescents, age >2 years) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | The loss of clinical attachment level (CAL) is greater in patients with cleft lip and palate than in healthy controls (p < 0.00001) | NR | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 6: superficial discoloration · Continent: Africa Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.31 [0.18, 0.51] | 2 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 region: West Asia Multimorbidity patterns of dental caries and obesity/overweight among adults: a systematic review and… (2025) | OR 1.23 [0.96, 1.50] | NR | Ungraded |
Intervention NR Tooth survival · - The effectiveness of partial pulpotomy compared with full pulpotomy in managing deep caries in vital… (2025) | no estimate extracted | 0 studies | No studies |
Microinvasive techniques (resin infiltration, resin/GIC sealant, or glass ionomer varnish) vs Non-invasive measures (fluoride varnish/toothpaste, flossing, oral hygiene instruction, sham/standard of care) Adverse events and periodontal/secondary outcomes (gingival bleeding, gingival bleeding index, visible plaque index) · Children and adults with non-cavitated proximal (interproximal) caries lesions in primary and/or permanent teeth (ages… · Baseline and follow-up Microinvasive interventions in the management of proximal caries lesions in primary and permanent teeth-… (2025) | Reported narratively by 3 trials (Arthur 2018, Sarti 2020, Jorge 2019). No adverse events were attributed to microinvasive treatment. Gingival bleeding index: no significant difference in Arthur 2018 and Jorge 2019 but… | 3 studies | Ungraded |
Intervention NR Specificity · Imaging modality: Periapical radiographs Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Specificity 0.88 [0.82, 0.93] | 12 studies | Ungraded |
Partial pulpotomy with calcium hydroxide 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, Calcium hydroxide Partial pulpotomy for carious pulp exposure in adult mature permanent teeth: a systematic review and… (2025) | Success rate (%) 34.3 [24.93, 43.67] | NR | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of fragility fractures · Females aged over 50 years · Long-term / lifetime fluoride exposure, Females over 50 years: drinking-water fluoride 0.45 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 1.00 [0.80, 1.24] | NR | Ungraded |
Self-assembling/remineralizing peptide (e.g., P11-4, PAA-PASP) 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 18.295 [14.418, 22.172] | 3 studies | Moderate |
Artificial intelligence algorithms for caries detection vs Dental expert or visual-tactile/clinical assessment as reference standard Negative post-test probability · Dental images or diagnostic tests for dental caries detection · Overall (all imaging modalities pooled) Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Post-test probability 0.06 | 20 studies | Ungraded |
Intervention NR Amalgam: 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 5.97 [4.09, 8.70] | NR | Ungraded |
Intervention NR Bleeding on Probing (BoP) · Cleft lip/palate vs healthy controls Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | no estimate extracted | 1 study | Ungraded |
HIV infection with antiretroviral therapy (ART/HAART) vs HIV-negative individuals Dental caries (presence/absence) · Children and adolescents under 18 years with HIV · Not specified (case-control), Case-control studies Association between antiretroviral therapy and dental caries in children and adolescents with HIV: a… (2025) | OR 3.15 [0.98, 10.15] | 1 study · 99 participants | Very low |
Intervention NR Composite: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · HDI: High Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 11.31 [6.70, 19.08] | 7 studies | Ungraded |
E-cigarette use (electronic nicotine delivery systems / vaping) vs Non-smokers (non-users) Oral microbiota composition (dysbiosis; increased periodontal/opportunistic pathogens) · Adult e-cigarette (ENDS) users (general oral health; predominantly natural dentition) An Umbrella Review of E-Cigarettes' Impact on Oral Microbiota and Biofilm Buildup. (2025) | Narrative synthesis: reviews reported oral microbiota dysbiosis in e-cigarette users, including increased Porphyromonas gingivalis and Fusobacterium nucleatum and microbial shifts predisposing to oral infection… | 5 studies | Ungraded |
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), Etch-and-Rinse + chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD -0.288 [-7.988, 7.411] | 0 studies | Very low |
Digital gamified oral health interventions (mobile apps, serious games, augmented reality) vs Non-digital gamified oral health interventions (card/board games, storytelling, printed aids) Long-term behavior change and overall oral health outcomes · Children and adolescents aged <=18 years · Long-term follow-up (sustained behavior change) The Application of Gamification in Children's Oral Health Management: Systematic Review. (2025) | Digital-based interventions were more effective in fostering long-term behavior change compared with nondigital alternatives and consistently outperformed nondigital alternatives in improving oral health outcomes;… | NR | Ungraded |
Gamified mobile health app vs Nongamified intervention Regular use rate · Children and adolescents aged 18 years or younger · Digital mobile app The Application of Gamification in Children's Oral Health Management: Systematic Review. (2025) | Regular use rate 72.4% (gamified mobile app) vs 48.3% (nongamified) | 1 study · In one study, the regular use rate was significantly higher (72.4%) in the gamified mobile health app group than in the nongamified intervention group (48.3%). participants | Ungraded |
Early childhood caries vs Caries-free controls Number of detected salivary bacterial genera · Young children with early childhood caries and caries-free controls A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | Number of genera caries-affected 117 vs caries-free 123 genera | 1 study · 40 participants | Ungraded |
Early childhood caries vs Caries-free controls Relative abundance of dominant salivary microbial community (7 genera) · Young children with early childhood caries and caries-free controls A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | Relative abundance (%) caries-affected 75% vs caries-free 74% | 1 study · 40 participants | Ungraded |
Ion-releasing restorations (IRR): RMGIC, HVGIC, GIC, compomer/PMRC, giomer vs Composite resin (CR), including bulk-fill composite Adequate marginal or tooth integrity · 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 [0.99, 1.01] | 6 studies · 930 participants | High |
Hydroxyapatite (e.g., nano-HAp) 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 -4.815 [-10.709, 1.079] | 0 studies | Moderate |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability, adjusted for DMFS Forearm fracture · European GWAS participants · MVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.992 [0.950, 1.036] | 490889 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 behavior · Children and adolescents aged 5-18 years · Post-intervention (follow-up 0.5 to 24 months, varies by study), Overall Health promotion theory-based educational interventions for improving oral health in children and… (2025) | SMD 2.58 [2.03, 3.12] | 6 studies · 13973 participants | Low |
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 · Overall (all dentition) Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025) | Sensitivity 0.86 | 4 studies | Ungraded |
HAART (highly active antiretroviral therapy, >=3 drugs) vs HIV-positive not receiving HAART (standard ART or HAART-naive) Dental caries (presence/absence) · Children and adolescents under 18 years with HIV · Not specified (cross-sectional), Cross-sectional studies; deft index Association between antiretroviral therapy and dental caries in children and adolescents with HIV: a… (2025) | OR 1.09 [0.65, 1.82] | NR | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of fractures (any site) · General population (both sexes, all ages) · Long-term / lifetime fluoride exposure, Drinking-water fluoride 4.0 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 1.35 [0.94, 1.95] | 4 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 5: open margin · HDI: Medium Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.90 [0.78, 4.64] | 2 studies | Ungraded |
Ion-releasing restorations (IRR): RMGIC, HVGIC, GIC, compomer/PMRC, giomer vs Composite resin (CR), including bulk-fill composite Adequate color or translucency · 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 1.02 [0.97, 1.07] | 6 studies · 600 participants | Moderate |
Peptide vs Silica Immediate (24 h) resin-dentin bond strength (MPa) · permanent human teeth with artificial caries-affected dentin · 24 h, Self-Etch; chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD -0.690 [-7.941, 6.560] | 0 studies | Moderate |
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 · High inequality Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | MEAN 75.3 [67.1, 83.6] | NR | Ungraded |