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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.
10,375 questions in 429 reviews · Oral Health
current versionsNo studies 1,344 · 13%Ungraded 6,832 · 65.9%Very low 1,228 · 11.8%Low 613 · 5.9%Moderate 290 · 2.8%High 68 · 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 |
|---|---|---|---|
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 |