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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 |
|---|---|---|---|
Anorexia nervosa (as exposure; diagnosed by DSM-III/III-R/IV/V) vs Healthy individuals without anorexia nervosa (age- and sex-matched controls) Gingival (marginal) recession · Patients with anorexia nervosa aged >=12 years (mean age ~18.4; entirely female in reported data), general… The influence of anorexia nervosa on oral health and related parameters potentially relevant to orthodontic… (2025) | Marginal/gingival recession significantly higher in anorexia nervosa patients (Pallier 2.8% vs 0.0%, p<0.01; Touyz 10.2% vs 2.0%, p<0.001); not meta-analyzed | 2 studies · 136 participants | Ungraded |
Severe early childhood caries vs Caries-free controls Veillonella spp. and Streptococcus mutans interaction · 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) | Veillonella spp. may promote proliferation or survival of cariogenic species, as shown for interactions between Veillonella spp. and S. mutans. | 1 study · 82 participants | Ungraded |
HAART (highly active antiretroviral therapy, >=3 drugs) vs HIV-positive not receiving HAART (standard ART or HAART-naive) Dental caries severity (dmft index, primary 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 0.66 [-0.26, 1.58] | NR | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Osteoporosis with pathological fracture · European GWAS participants · SVMR Maximum Likelihood From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.278 [0.921, 1.773] | 376746 participants | 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 · Permanent dentition Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025) | Sensitivity 0.76 | 3 studies | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of wrist fractures · General population (both sexes, all ages) · Long-term / lifetime fluoride exposure, Drinking-water fluoride 0.01 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 1.00 [0.99, 1.01] | NR | Ungraded |
HIV infection with antiretroviral therapy (ART/HAART) vs HIV-negative individuals Dental caries severity (DMFS index, permanent dentition) · Children and adolescents under 18 years with HIV · Not specified (cross-sectional), Cross-sectional studies; DMFS index Association between antiretroviral therapy and dental caries in children and adolescents with HIV: a… (2025) | MD 2.00 [1.54, 2.46] | 1 study · 778 participants | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of fragility fractures · Females (all ages) · Long-term / lifetime fluoride exposure, Females: drinking-water fluoride 0.9 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 1.00 [0.79, 1.27] | NR | Ungraded |
Anorexia nervosa (as exposure; diagnosed by DSM-III/III-R/IV/V) vs Healthy individuals without anorexia nervosa (age- and sex-matched controls) Dental erosion · Patients with anorexia nervosa aged >=12 years (mean age ~18.4; entirely female in reported data), general… The influence of anorexia nervosa on oral health and related parameters potentially relevant to orthodontic… (2025) | Significant prevalence of dental erosion in anorexic patients vs controls, though BEWE scores indicated low erosive-wear risk (Mascitti BEWE 5.2+/-4.5; Paszynska 16.2% at BEWE 3-8); not meta-analyzed | 2 studies · 270 participants | Ungraded |
Intervention NR Lacunar stroke · Mediation via IL-1α, IL-6, TNF, CRP (two-step MR) The contribution of oral infectious diseases in lacunar stroke based on meta-analysis and Mendelian… (2025) | Indirect effect No mediating effect | NR | Ungraded |
Intervention NR Composite: 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 0.59 [0.39, 0.88] | 6 studies | Ungraded |
Flavonoids (e.g., quercetin, proanthocyanidin) 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 5.728 [-2.442, 13.897] | 0 studies | Moderate |
Hydroxyapatite (e.g., nano-HAp) 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 -7.520 [-14.758, -0.281] | 0 studies | Moderate |
Intervention NR Osteoporosis · DMFS, bias-corrected (MR-RAPS/Debiased IVW) From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.171 [1.051, 1.304] | NR | Ungraded |
Daily tooth brushing vs Reference (no/less brushing) Early childhood caries (ECC) · Children aged 0-5 years in North Africa · Once daily Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 0.033 [0.004, 0.263] | 1 study | Ungraded |
Intervention NR Caregiver-reported child brushing frequency · Gamified applications (nonexperimental studies) The Application of Gamification in Children's Oral Health Management: Systematic Review. (2025) | Proportion (caregiver report) 58.8% of caregivers reported their children brushed more often when using gamified applications | 1 study | Ungraded |
Lacunar stroke (cases) vs Without lacunar stroke (controls) Periodontal probing depth (PD) · Adults The contribution of oral infectious diseases in lacunar stroke based on meta-analysis and Mendelian… (2025) | MD 0.98 [0.57, 1.38] | 4 studies | Ungraded |
AI systems for caries detection/segmentation on dental X-ray images (predominantly convolutional neural networks; also ANNs, DNNs, DCNN, FCNN, SVMs, decision trees, random forests; e.g. EfficientNet, ResNet, AlexNet) vs Human dentists / trained dental professionals or traditional radiographic interpretation (reference standard / reference models) Diagnostic accuracy (prevalence of accuracy) · Patients undergoing dental X-ray (radiographic) imaging for caries detection · Overall (all X-ray types pooled) Accuracy of artificial intelligence in caries detection: a systematic review and meta-analysis. (2025) | OR 2.72 [14.65, 14.65] | 14 studies | Ungraded |
Quantitative light-induced fluorescence (QLF) vs Reference standard (histology; some ICDAS/radiography) Occlusal caries detection: specificity · Extracted human teeth (in vitro); permanent and primary teeth, occlusal surfaces · Primary dentition Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025) | Specificity 0.81 | 2 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 3: secondary caries · Continent: Europe Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 6.53 [4.35, 9.81] | 6 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · Continent: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.80 [0.59, 1.07] | 11 studies | Ungraded |
Intervention NR Sensitivity · Imaging modality: Bitewing radiographs Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Sensitivity 0.81 [0.72, 0.91] | 5 studies | Ungraded |
Higher national income (GNI per capita) vs Lower national income (GNI categories: middle <=$15,000 / high $15,001-25,000 / very high >$25,000) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), Middle income (GNI <=$15,000) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 3.30 [2.57, 4.03] | 12 studies | Ungraded |
Intervention NR Altered cariogenic-biofilm composition/architecture with reduced abundance of cariogenic species · In vitro (multispecies biofilm) Postbiotics and Dental Caries: A Systematic Review. (2025) | no estimate extracted | 1 study | Ungraded |
Caries-active status vs Caries-free status Prevalence (detection frequency) of S. mutans in saliva · Healthy caries-active and caries-free individuals · Saliva sample Streptococcus mutans and Caries: A Systematic Review and Meta-Analysis. (2025) | OR 3.12 [2.02, 4.83] | 6 studies · 490 participants | 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 · 6 months, 6-month follow-up Comparative success of minimally invasive treatments for cavitated caries in primary teeth: a network… (2025) | OR 4.87 [1.23, 19.30] | 44 studies | Moderate |
Periodontitis vs Without periodontitis Lacunar stroke · Adults The contribution of oral infectious diseases in lacunar stroke based on meta-analysis and Mendelian… (2025) | OR 5.16 [3.68, 7.24] | 3 studies | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Lumbar spine and pelvis fracture · European GWAS participants · SVMR Maximum Likelihood From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.055 [0.983, 1.132] | 490700 participants | Ungraded |
Electronic cigarette use vs Non-smokers IL-8 level · People who use electronic cigarettes · Overall The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d -0.43 [-1.02, 0.14] | 6 studies | Ungraded |
Dental treatments including dental care and services Willingness to pay for dental care · 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 examining willingness to pay 37 | 37 studies | Ungraded |
HIV infection with antiretroviral therapy (ART/HAART) vs HIV-negative individuals Dental caries severity (DMFS index, permanent dentition) · Children and adolescents under 18 years with HIV · Not specified (case-control), Case-control studies; DMFS index Association between antiretroviral therapy and dental caries in children and adolescents with HIV: a… (2025) | MD 1.10 [-0.25, 2.45] | 1 study · 105 participants | Ungraded |
Artificial intelligence algorithms for caries detection vs Dental expert or visual-tactile/clinical assessment as reference standard Diagnostic odds ratio · 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) | DOR 70.9 [44.9, 111.9] | 20 studies | 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), Self-Etch + chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD -0.601 [-2.932, 1.730] | 8 studies | Moderate |
Hall technique vs Silver-modified atraumatic restorative treatment (SMART) Treatment success (caries lesion arrest or restoration survival) · Children (aged 3-11 y) with cavitated caries lesions in primary teeth · 6 months, 6-month follow-up Comparative success of minimally invasive treatments for cavitated caries in primary teeth: a network… (2025) | OR 5.61 [1.36, 23.08] | 44 studies | Moderate |
Lacunar stroke (cases) vs Without lacunar stroke (controls) Full-mouth bleeding score (FMBS) · Adults The contribution of oral infectious diseases in lacunar stroke based on meta-analysis and Mendelian… (2025) | MD 31.26 [28.82, 33.70] | 3 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · Continent: Africa Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 10.88 [4.01, 29.56] | 2 studies | 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), HDI: Very high Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 2.99 [1.91, 4.67] | 10 studies · 1754 participants | Ungraded |
Anorexia nervosa (as exposure; diagnosed by DSM-III/III-R/IV/V) vs Healthy individuals without anorexia nervosa (age- and sex-matched controls) Dental plaque accumulation (plaque index) · Patients with anorexia nervosa aged >=12 years (mean age ~18.4; entirely female in reported data), general… The influence of anorexia nervosa on oral health and related parameters potentially relevant to orthodontic… (2025) | In 2 of 3 studies anorexic patients had significantly higher plaque accumulation than controls (Pallier 78.8% vs 53.0%, p<0.01; Paszynska 43.8% vs 13.7%, p<0.001; Milosevic 84% vs 72%, NS); not meta-analyzed | 3 studies · 394 participants | Ungraded |
Experience of dental caries (caries history, e.g. DMFT) vs Adolescents without dental caries Negative oral-health impact on daily performance (OIDP or Child-OIDP) · Adolescents aged 10 to 19 years · Cross-sectional (concurrent exposure and outcome); oral impacts recalled over the prior 6 months, Caries-definition subgroup: experience of dental caries Impact of dental caries on the quality of life of adolescents: A systematic review and meta-analysis. (2025) | PR 1.72 [1.23, 2.43] | 6 studies | Ungraded |
Microinvasive techniques (mostly resin infiltration; incl. resin sealant) vs Non-invasive measures (fluoride varnish/toothpaste, flossing, oral hygiene instruction, sham/standard of care) Radiographic progression of proximal caries lesions · Children and adults with non-cavitated proximal caries lesions in permanent teeth (ages 11-45) · Final follow-up (1 to 7 years across trials), Permanent teeth (Fig. 6, subgroup 2.1.1) Microinvasive interventions in the management of proximal caries lesions in primary and permanent teeth-… (2025) | OR 0.18 [0.10, 0.32] | 7 studies · 296 participants | Ungraded |
High dental-caries prevalence vs Not applicable OHRQoL sum score transformed to 0-100 · Community-dwelling adults aged 60 years or older · Baseline for longitudinal studies, High dental-caries prevalence Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | 71.40 [64.16, 78.63] | NR | 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 (binary; DMFT-based or dentist-diagnosed caries present) · Adults (≥18 years) · By BMI classification: obesity (vs study-defined non-obese: normal or low weight) Multimorbidity patterns of dental caries and obesity/overweight among adults: a systematic review and… (2025) | OR 1.04 [0.85, 1.23] | NR | 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: Medium Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 5.19 [3.61, 7.45] | 2 studies · 353 participants | Ungraded |
Fluoride mouthrinse (0.05-0.32% sodium fluoride or amine fluoride) added to daily fluoride toothpaste vs Control: fluoride toothpaste alone, placebo mouthrinse + toothpaste, or non-fluoride (chlorhexidine) mouthrinse + toothpaste Incidence of initial enamel caries / white spot lesions adjacent to bracket base (subject level, dichotomized) · Children, adolescents and adults undergoing fixed (multi-bracket) orthodontic treatment · End of intervention (6-26 months) to within 6 weeks after debonding Fluoride mouthrinses for prevention of initial caries in orthodontic patients - a systematic review and… (2025) | RD -0.07 [-0.14, -0.01] | 5 studies · 491 participants | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 6: corrosion · Continent: South America Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 2.13 [0.84, 5.39] | 2 studies | Ungraded |
Postbiotic toothpaste vs Fluoride toothpaste Salivary immunoglobulin A and pH · Children aged 6 to 12 years · 4 weeks Postbiotics and Dental Caries: A Systematic Review. (2025) | no estimate extracted | 1 study | 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 · Very high HDI Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | MEAN 78.4 [71.1, 85.8] | NR | Ungraded |
Microinvasive technique (proximal sealing) vs No intervention Radiographic progression of proximal caries lesions · Children with lesions in both primary and permanent teeth (ages 8-10) · 3.5 years, Both permanent and primary (Fig. 6, subgroup 2.1.3) Microinvasive interventions in the management of proximal caries lesions in primary and permanent teeth-… (2025) | OR 0.16 [0.06, 0.44] | 1 study · 61 participants | Ungraded |
Self-assembling/remineralizing peptide (e.g., P11-4, PAA-PASP) vs Fluoride agent (e.g., NaF/SDF/KF/CaF2) 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 4.672 [-1.320, 10.665] | 2 studies | Moderate |
HIV infection with antiretroviral therapy (ART/HAART) vs HIV-negative individuals Dental caries (presence/absence) · Children and adolescents under 18 years with HIV · Prospective follow-up (single cohort), Cohort studies Association between antiretroviral therapy and dental caries in children and adolescents with HIV: a… (2025) | OR 2.11 [1.41, 3.17] | 1 study · 544 participants | Very low |