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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 |
|---|---|---|---|
HIV-infected children on antiretroviral therapy (HI) vs HIV-unexposed uninfected children (HUU) 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 1.61 [1.02, 2.56] | NR | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 6: corrosion · HDI: Very high Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.54 [1.03, 2.32] | 10 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · Continent: Europe Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 2.03 [1.35, 3.04] | 6 studies | Ungraded |
Higher parental education (tertiary) vs Lower parental education (reference) Early childhood caries (ECC) · Children aged 0-5 years in North Africa · Parents' education level [Chouchene] Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 0.797 [0.171, 0.650] | 1 study | Ungraded |
Self-assembling/remineralizing peptide (e.g., P11-4, PAA-PASP) vs Flavonoids (e.g., quercetin, proanthocyanidin) 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 9.857 [2.588, 17.126] | 0 studies | Moderate |
AI algorithms (predominantly CNN/deep learning) as index test vs Dental expert / visual-tactile clinical assessment (reference standard) Log diagnostic odds ratio · 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) | Log DOR 4.37 [3.16, 6.27] | 20 studies · 29423 participants | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Lumbar spine bone mineral density (BMD) · Females aged over 50 years · Long-term / lifetime fluoride exposure, Females >50, spine BMD dose-response The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | Inverted U-shaped curve with a downward trend starting at lower fluoride concentrations than the overall analysis (no numeric MD reported in text) | NR | Ungraded |
Intervention NR Radiographic progression of proximal caries lesions · Caries depth: lesions extending beyond DEJ (favored microinvasive; narrative, no numeric estimate) Microinvasive interventions in the management of proximal caries lesions in primary and permanent teeth-… (2025) | no estimate extracted | NR | Ungraded |
Hall technique vs Silver diamine fluoride (SDF) Treatment success (caries lesion arrest or restoration survival) · Children (aged 3-11 y) with cavitated caries lesions in primary teeth · 12 months, 12-month follow-up Comparative success of minimally invasive treatments for cavitated caries in primary teeth: a network… (2025) | OR 3.23 [1.13, 9.22] | 43 studies | Moderate |
Electronic cigarette use vs Non-smokers IL-8 level · 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 -0.32 [-0.99, 0.35] | 5 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · Continent: South America Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 7.54 [3.41, 16.67] | 2 studies | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Osteoporosis · European GWAS participants · SVMR Maximum Likelihood From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.998 [0.934, 1.067] | 483725 participants | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 6: corrosion · Coverage: Covering cost of minimally invasive treatment Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.66 [1.11, 2.49] | NR | Ungraded |
Severe early childhood caries vs Caries-free controls Streptococcus mutans relative abundance · Children under 6 years with severe early childhood caries and caries-free controls A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | Median relative abundance (%) caries 0.73 (range 0.02-22.9) vs control 0.15 (0.006-10.4) | 1 study · 50 participants | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of fragility fractures · Males · Long-term / lifetime fluoride exposure, Males: drinking-water fluoride 0.57 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 0.83 [0.72, 0.97] | 7 studies | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS, adjusted for periodontitis 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 0.105 [0.011, 0.199] | 28498 participants | Ungraded |
Replacement of the defective restoration vs Repair of the defective restoration Amalgam: Preference for replacement over repair - Scenario 4: marginal discoloration · 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), HDI: Low Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 3.58 [2.74, 4.69] | 2 studies · 350 participants | Ungraded |
Breastfeeding for 12-24 months vs Not breastfed at the same age Risk 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) | RR 1.21 [0.82, 1.78] | 5 studies | Low |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Osteoporosis · European GWAS participants · SVMR Maximum Likelihood From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.162 [0.998, 1.353] | 483725 participants | Ungraded |
Intervention NR Amalgam: 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 6.44 [4.85, 8.56] | 2 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · Continent: Europe Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 3.53 [2.36, 5.30] | 6 studies | Ungraded |
Intervention NR Composite: 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 4.75 [2.78, 8.11] | 10 studies | 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) Dental plaque (plaque index) · Children and adolescents aged 5-18 years · Post-intervention (follow-up 1 to 24 months, varies by study), Overall Health promotion theory-based educational interventions for improving oral health in children and… (2025) | SMD -1.92 [-2.42, -1.42] | 9 studies · 12562 participants | Moderate |
Self-assembling/remineralizing peptide (e.g., P11-4, PAA-PASP) vs Flavonoids (e.g., quercetin, proanthocyanidin) 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 -3.074 [-10.755, 4.607] | 0 studies | Moderate |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) Postmenopausal osteoporosis with pathological fracture · Postmenopausal women (European ancestry) · Lifelong genetic liability, MVMR (IVW), adjusted for DMFS From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.016 [0.867, 1.191] | 281786 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 · Sampling: convenience Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 60 | 4 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · Coverage: Not covering Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.40 [0.30, 0.55] | NR | Ungraded |
Quantitative light-induced fluorescence (QLF) vs Reference standard (bitewing radiography, ADA classification, ICDAS II) Proximal caries detection: sensitivity · Patients (in vivo); permanent and primary teeth, proximal (approximal) surfaces · Overall (all dentition) Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025) | Sensitivity 0.74 | 4 studies | Ungraded |
Gamified oral health interventions (mobile apps, serious games, augmented reality, game-based education) vs Conventional or traditional oral health education, or non-gamified interventions (comparator varied; several studies were single-arm/uncontrolled) Oral hygiene behavior (brushing habits, preventive dental visits, dietary choices) · Children and adolescents aged <=18 years · Post-intervention (predominantly short-term; long-term follow-up in a minority of studies) The Application of Gamification in Children's Oral Health Management: Systematic Review. (2025) | A gesture-based motion-capture game enhanced brushing independence and skill retention (P<.001) [Kang 2021]; 58.8% of caregivers reported their children brushed more often when using gamified applications [France… | NR | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Forearm fracture · European GWAS participants · SVMR Weighted Median From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.914 [0.799, 1.046] | 490889 participants | Ungraded |
Hydroxyapatite (e.g., nano-HAp) 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 4.841 [-0.848, 10.530] | 3 studies | Low |
Severe early childhood caries vs Caries-free controls Streptococcus relative abundance · Children under 6 years with severe early childhood caries and caries-free controls A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | Mean relative abundance (%) caries 35.63 (SD 17.04) vs control 32.11 (SD 18.91) | 1 study · 9 (caries only; control not reported in Table 3) participants | Ungraded |
Timing of first dental visit vs Reference visit timing Early childhood caries (ECC) · Children aged 0-5 years in North Africa · Delayed/late visit Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 0.248 [0.072, 0.852] | 1 study | Ungraded |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) Fracture of femur · 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 1.126 [0.975, 1.300] | 489106 participants | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 6: superficial discoloration · HDI: Very high Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.26 [0.14, 0.49] | 10 studies | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Osteoporosis · European GWAS participants · SVMR Weighted Median From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.002 [0.925, 1.086] | 483725 participants | 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: 0.20 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | MD 0.02 [-0.02, 0.07] | NR | Ungraded |
Intervention NR Early childhood caries (ECC), prevalence · Study site: urban and rural (both) Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 51 [35, 67] | 7 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 6: superficial discoloration · Continent: South America Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.44 [0.15, 1.29] | 2 studies | 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) Postoperative pain and analgesic intake · Adults (18-45 y) with mature permanent molars, carious exposure and symptomatic irreversible pulpitis · Postoperative days 1-2, Lateral extent of pulp amputation Partial pulpotomy for carious pulp exposure in adult mature permanent teeth: a systematic review and… (2025) | Same RCT (Ramani 2024): restricted PP had significantly lower postoperative pain scores on days 1 and 2 (p<0.05) and required significantly less analgesic intake (p<0.05) than extended PP. | 1 study · 96 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 · Sampling: stratified/multistage cluster Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 50 [40, 61] | 9 studies | Ungraded |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) Osteoporosis · 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 0.998 [0.933, 1.067] | 483725 participants | Ungraded |
Partial pulpotomy vs Full (complete) pulpotomy Oral health-related quality of life (OHRQoL) · Mature permanent (molar) teeth with deep caries and symptoms indicative of irreversible pulpitis (spontaneous pain) · >=6 months The effectiveness of partial pulpotomy compared with full pulpotomy in managing deep caries in vital… (2025) | no estimate extracted | 0 studies | No studies |
Cessation of breastfeeding/bottle after 18 months vs Cessation at or before 18 months Early childhood caries (ECC) · Children aged 0-5 years in North Africa · >18 months Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 2.417 [1.340, 4.358] | 1 study | Ungraded |
Postbiotic products (postbiotic toothpaste; heat-killed/postbiotic oral lozenges; inactivated-bacteria tablets) vs Placebo, fluoride toothpaste, or standard post-filling care (varies by trial) Reduced salivary S. mutans counts · Humans at risk of dental caries (children aged 6-12 years; adults with dental caries) · Daily for 14 days to 4 weeks Postbiotics and Dental Caries: A Systematic Review. (2025) | Three RCTs reported reduced salivary S. mutans counts after postbiotic intervention; the reduction was statistically significant in Lin 2022 but non-significant in Basir 2022; no pooled estimate. | 3 studies | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS, adjusted for periodontitis 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 1.011 [0.876, 1.167] | 376746 participants | Ungraded |
Partial pulpotomy (PP) with calcium hydroxide vs Direct pulp capping (DPC) with calcium hydroxide Clinical and radiographic success rate · Adults (>=18 y) with mature permanent teeth, carious exposure and normal/reversibly inflamed pulp · 1 year Partial pulpotomy for carious pulp exposure in adult mature permanent teeth: a systematic review and… (2025) | Success rate (%) 34.5 vs 31.8 | 1 study · 51 participants | Ungraded |
Out-of-pocket health expenditure vs Lower vs higher out-of-pocket expenditure categories Oral health-related quality of life (OHRQoL sum score, transformed 0-100) · Community-dwelling elderly persons aged ≥60 years · Lowest out-of-pocket expenditure Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | MEAN 83.9 [75.2, 92.6] | NR | Ungraded |
E-cigarette use (electronic nicotine delivery systems / vaping) vs Non-smokers (non-users) Periodontitis / periodontal disease and periodontal parameters · 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: e-cigarette use associated with increased risk of periodontal and gingival disease and worse periodontal parameters vs non-smokers (Tattar, Shabil, Figueredo, Yang [23,24,30,31]); no pooled… | 7 studies | Ungraded |
Replacement of the defective restoration vs Repair of the defective restoration Amalgam: Preference for replacement over repair - Scenario 4: marginal discoloration · 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 6.04 [4.51, 8.08] | 21 studies · 3680 participants | Ungraded |