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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.

Limit to evidence status or GRADE (optional)

75,239 questions in 5,342 reviews

current versions
No 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.

QuestionEffectEvidenceStatus / 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]NRUngraded
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 studiesUngraded
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]NRUngraded
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 studiesModerate
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 participantsUngraded
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 participantsVery 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 participantsUngraded
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 studiesUngraded
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 studyUngraded
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 studiesUngraded
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 participantsUngraded
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 participantsUngraded
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 studiesHigh
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 studiesUngraded
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]NRUngraded
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 studiesUngraded
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 studiesUngraded
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).NRUngraded
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 participantsUngraded
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)NRUngraded
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 studiesUngraded
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]NRUngraded
Intervention NR
Tooth survival · -
The effectiveness of partial pulpotomy compared with full pulpotomy in managing deep caries in vital… (2025)
no estimate extracted0 studiesNo 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 studiesUngraded
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 studiesUngraded
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]NRUngraded
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]NRUngraded
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 studiesModerate
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 0.0620 studiesUngraded
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]NRUngraded
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 extracted1 studyUngraded
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 participantsVery 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 studiesUngraded
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 studiesUngraded
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 studiesVery 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;…NRUngraded
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%). participantsUngraded
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 genera1 study · 40 participantsUngraded
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 participantsUngraded
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 participantsHigh
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 studiesModerate
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 participantsUngraded
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 participantsLow
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 0.864 studiesUngraded
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]NRUngraded
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 studiesUngraded
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 studiesUngraded
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 participantsModerate
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 studiesModerate
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]NRUngraded