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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
Dental caries (presence or experience) vs Adolescents without dental caries
Negative oral-health impact on daily performance measured by Child-OIDP · Adolescents aged 10 to 19 years · Cross-sectional (concurrent exposure and outcome); oral impacts recalled over the prior 6 months, Instrument subgroup: Child-OIDP
Impact of dental caries on the quality of life of adolescents: A systematic review and meta-analysis. (2025)
PR 1.66 [1.19, 2.31]6 studiesUngraded
Cavity liner (calcium hydroxide, glass-ionomer cement, resin-modified calcium silicate/TheraCal LC, hydraulic calcium silicate/MTA or Biodentine, flowable composite, or other liner material) vs No cavity liner or a different liner material
Restoration longevity · Patients with deep caries lesions in mature or immature permanent (posterior) teeth, with no symptoms or reversible… · >=12 months
Efficacy of different cavity liners compared to no cavity lining in managing deep caries in vital permanent… (2025)
No significant difference; high success in all groups8 studies · 889 participantsLow
Low tooth brushing frequency (<2 times/day) vs High tooth brushing frequency (>=2 times/day)
Early childhood caries (presence/prevalence/severity by dmft/dmfs) · Healthy children under 6 years of age (6 months to 6 years); preschool children · Leave-one-out sensitivity analysis (Alhabdan 2018 outlier excluded, k=7)
Optimal tooth brushing initiation age and frequency for preventing early childhood caries: a systematic… (2025)
OR ~2.07 studiesUngraded
Low edentulism prevalence vs Not applicable
OHRQoL sum score transformed to 0-100 · Community-dwelling adults aged 60 years or older · Baseline for longitudinal studies, Low edentulism prevalence
Association between oral health-related quality of life and structural determinants of health among elderly… (2025)
There were no statistically significant differences reported in the OHRQoL sum scores based on prevalence of edentulism.NRUngraded
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS, adjusted for periodontitis
Femur fracture · European GWAS participants · MVMR MR-Egger
From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025)
OR 0.820 [0.618, 1.087]489106 participantsUngraded
Intervention NR
Composite: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · HDI: Low
Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025)
RR 0.27 [0.22, 0.34]2 studiesUngraded
Intervention NR
Oral hygiene improvement · Gamified group (reminder sticker book, rewards and visual aids)
The Application of Gamification in Children's Oral Health Management: Systematic Review. (2025)
Narrative (P value) Significant improvement in oral hygiene in gamified group (P<.001)1 studyUngraded
Prolonged breastfeeding for more than 24 months vs Not breastfed at the same age or breastfed for a shorter duration
Early childhood caries (ECC) - incidence/risk · Children up to 71 months (early childhood; primary dentition) · Up to 71 months of age (study follow-up 1-9 years), More than 24 months
Risk of Early Childhood Dental Caries Associated With Prolonged Breastfeeding: A Systematic Review and… (2025)
RR 2.44 [1.97, 3.02]2 studiesLow
Intervention NR
Treatment failure (time-to-failure, 7 years) · Resin infiltration 1.3% vs standard of care 7.8% (Paris 2020, Kaplan-Meier)
Microinvasive interventions in the management of proximal caries lesions in primary and permanent teeth-… (2025)
no estimate extracted1 studyUngraded
Intervention NR
Composite: 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 0.91 [0.54, 1.54]2 studiesUngraded
Glass ionomer (modified glass ionomer varnish) vs Non-invasive measures (standard of care)
Radiographic progression of proximal caries lesions · Children with non-cavitated proximal caries lesions in primary teeth (ages 5-8) · 1 year, Glass ionomer vs non-invasive (Fig. 5, subgroup 2.1.3)
Microinvasive interventions in the management of proximal caries lesions in primary and permanent teeth-… (2025)
OR 0.58 [0.28, 1.20]1 study · 53 participantsUngraded
Intervention NR
Amalgam: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · HDI: Medium
Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025)
RR 2.42 [0.37, 15.80]2 studiesUngraded
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability
Lumbar spine and pelvis fracture · European GWAS participants · SVMR Weighted Median
From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025)
OR 1.058 [0.966, 1.158]490700 participantsUngraded
E-cigarette use (ENDS / vaping) vs Non-smokers
Interleukin-8 (IL-8) · Humans who use e-cigarettes (mostly adults, often with periodontal disease) assessed for oral proinflammatory markers · Cross-sectional (single time point) for most; a few 6-month prospective, Overall (saliva + GCF)
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 studiesUngraded
E-cigarette use (ENDS / vaping) vs Non-smokers
Dental caries experience (DMFT/DMFS index) · Humans who use e-cigarettes (adolescents to adults) assessed for dental caries · Cross-sectional to 6 months
The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025)
Cohen's d 0.93 [-1.11, 2.98]3 studiesUngraded
Breastfeeding for more than 12 months vs Not breastfed at the same age
Prevalence of early childhood caries · Children up to 71 months · More than 12 months
Risk of Early Childhood Dental Caries Associated With Prolonged Breastfeeding: A Systematic Review and… (2025)
OR 1.86 [1.48, 2.35]13 studiesLow
Lower unemployment rate vs Higher unemployment rate (low <=5% / medium >5-10% / high >10%)
Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), Low unemployment (<=5%)
Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025)
MEAN 1.23NRUngraded
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS, adjusted for periodontitis
Forearm fracture · European GWAS participants · MVMR MR-Egger
From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025)
OR 0.901 [0.751, 1.081]490889 participantsUngraded
Mesoporous silica (SiO2) 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), Self-Etch + chemical ACAD
Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025)
MD 1.441 [-5.099, 7.980]0 studiesModerate
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability
Osteoporosis · European GWAS participants · SVMR MR-Egger
From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025)
OR 1.001 [0.918, 1.093]483725 participantsUngraded
Simple childhood caries prediction models with at least two predictors vs No competing model
Dental caries discrimination (area under the curve) · Children and adolescents (≤18 years) · Validation assessment; prediction horizon not reported
Risk prediction models for dental caries in children and adolescents: a systematic review and meta-analysis. (2025)
AUC 0.766 [0.761, 0.771]1 studyUngraded
HIV-infected children on antiretroviral therapy (HI) vs HIV-exposed but uninfected children (HEU)
Dental caries (presence/absence) · Children and adolescents under 18 years with HIV · Prospective follow-up, Cohort studies
Association between antiretroviral therapy and dental caries in children and adolescents with HIV: a… (2025)
OR 2.88 [1.71, 4.84]NRUngraded
Ion-releasing restorations (IRR): RMGIC, HVGIC, GIC, compomer/PMRC, giomer vs Composite resin (CR), including bulk-fill composite
Occlusion · Children receiving dental restorations (aged 4-11 years; primary teeth; Class I/II/V cavities) · 2 years
Clinical effectiveness of ion-releasing restorations compared to composite restorations in pediatric dental… (2025)
no estimate extracted1 studyUngraded
Quantitative light-induced fluorescence (QLF) vs Reference standard (ICDAS II visual examination, ADA classification, bitewing radiography)
Occlusal caries detection: specificity · Patients (in vivo); permanent and primary teeth, occlusal surfaces · Permanent dentition
Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025)
Specificity 0.803 studiesUngraded
Intervention NR
Amalgam: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · HDI: Low
Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025)
RR 5.34 [1.88, 15.19]2 studiesUngraded
Veillonella spp. abundance
Future caries · Children without a previous history of caries
A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025)
Among children without a previous history of caries, Veillonella spp., but not S. mutans or other acid-producing species, predicted future caries.1 study · NA (subgroup without prior caries history; n not reported) participantsUngraded
Replacement of the defective restoration vs Repair of the defective restoration
Amalgam: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · 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 1.70 [1.37, 2.10]21 studies · 3680 participantsUngraded
High edentulism prevalence vs Not applicable
OHRQoL sum score transformed to 0-100 · Community-dwelling adults aged 60 years or older · Baseline for longitudinal studies, High edentulism prevalence
Association between oral health-related quality of life and structural determinants of health among elderly… (2025)
There were no statistically significant differences reported in the OHRQoL sum scores based on prevalence of edentulism.NRUngraded
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability
Osteoporosis with pathological fracture · European GWAS participants · SVMR Weighted Median
From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025)
OR 0.985 [0.846, 1.146]376746 participantsUngraded
Partial pulpotomy vs Full (complete) pulpotomy
Patient- and clinical-reported outcomes (tooth survival, clinical/radiographic success, pain) · Asymptomatic permanent teeth with deep caries (no symptoms)
The effectiveness of partial pulpotomy compared with full pulpotomy in managing deep caries in vital… (2025)
no estimate extracted0 studiesNo studies
Dental treatments, care, and services (the decision context) vs None (no comparator defined)
Willingness-to-pay (WTP) for dental treatment · (Potential) patients with freedom of choice regarding dental treatments, including parents and caregivers deciding for…
Decision-making regarding dental treatments - What factors matter from patients' perspective? A systematic… (2025)
N=37 articles analyzed patients' willingness-to-pay (3 RCTs, 6 non-RCTs, 26 cross-sectional, 2 mixed-methods); most examined WTP for a specific treatment (N=29). WTP is higher for aesthetic than functional treatments…37 studiesUngraded
Intervention NR
Amalgam: Preference for replacement over repair - Scenario 4: marginal discoloration · Coverage: Covering cost of minimally invasive treatment
Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025)
RR 6.25 [4.50, 8.66]NRUngraded
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)
Engagement / adherence to oral hygiene routines · 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)
The regular use rate was significantly higher (72.4%) in the gamified mobile health app group than in the nongamified intervention group (48.3%) [Zolfaghari 2021]; quiz-based challenges in mobile apps encouraged higher…NRUngraded
Electronic cigarette use vs Non-smokers
TNF-α 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 0.23 [-0.62, 1.09]5 studiesUngraded
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 1.2 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]4 studiesUngraded
Dental treatments, care, and services (the decision context) vs None (no comparator defined)
Factors of choice influencing dental treatment decisions (overall) · (Potential) patients with freedom of choice regarding dental treatments, including parents and caregivers deciding for…
Decision-making regarding dental treatments - What factors matter from patients' perspective? A systematic… (2025)
n=101 factors of choice identified across 233 articles, grouped into three categories: (I) Dentist & dental institution (n=44 factors), (II) Patient (n=37), (III) Treatment (n=20); no effect sizes were pooled…233 studiesUngraded
Resin-based sealant (proximal sealing / fluoride-releasing resin sealant) vs Non-invasive measures (fluoride varnish; no intervention)
Radiographic progression of proximal caries lesions · Children and adults with non-cavitated proximal (interproximal) caries lesions in primary and/or permanent teeth (ages… · Final follow-up (1 to 3.5 years), Sealant vs non-invasive (Fig. 5, subgroup 2.1.2)
Microinvasive interventions in the management of proximal caries lesions in primary and permanent teeth-… (2025)
OR 0.24 [0.10, 0.55]2 studies · 111 participantsUngraded
Intervention NR
Oral health-related quality of life (OHRQoL sum score, transformed 0-100) · Overall (pooled across all studies)
Association between oral health-related quality of life and structural determinants of health among elderly… (2025)
MEAN 77.045 studiesUngraded
Dental treatments including dental care and services
Pain as a factor of choice · 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 identifying factor 4949 studiesUngraded
Anorexia nervosa (as exposure; diagnosed by DSM-III/III-R/IV/V) vs Healthy individuals without anorexia nervosa (age- and sex-matched controls)
Bleeding on probing (BOP) · 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)
MD 16.57 [12.89, 20.25]2 studies · 326 participantsLow
E-cigarette use (electronic nicotine delivery systems / vaping) vs Non-smokers (non-users)
Oral candidiasis / Candida spp. prevalence · 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 users showed a higher prevalence of Candida spp. (e.g., C. albicans) and increased fungal species compared with non-smokers (Ralho, Camoni [32,28]); no pooled estimate reported.2 studiesUngraded
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS)
Osteoporosis with pathological fracture · European-ancestry adults · Lifelong genetic liability, MVMR (IVW), adjusted for periodontitis
From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025)
OR 1.279 [0.955, 1.713]376746 participantsUngraded
Hydroxyapatite (e.g., nano-HAp) 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 -1.792 [-7.415, 3.831]0 studiesLow
Intervention NR
Clinical and radiographic success rate · Full meta-regression: preoperative diagnosis
Partial pulpotomy for carious pulp exposure in adult mature permanent teeth: a systematic review and… (2025)
Meta-regression No significant associationNRUngraded
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS
Postmenopausal 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 1.363 [0.955, 1.947]281786 participantsUngraded
Intervention NR
Composite: Preference for replacement over repair - Scenario 6: superficial discoloration · HDI: High
Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025)
RR 0.30 [0.19, 0.46]7 studiesUngraded
Dental treatments, care, and services (the decision context) vs None (no comparator defined)
Out-of-pocket payment / cost as a factor of choice · (Potential) patients with freedom of choice regarding dental treatments, including parents and caregivers deciding for…
Decision-making regarding dental treatments - What factors matter from patients' perspective? A systematic… (2025)
'Out-of-pocket payment' (and synonyms, e.g., 'cost') was the most frequently identified factor: mentioned in N=136 articles with the highest code frequency (n=151); most prevalent factor in 7 of the 8 countries with…136 studiesUngraded
Flavonoids (e.g., quercetin, proanthocyanidin) 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 + biological ACAD
Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025)
MD 4.241 [-2.652, 11.135]0 studiesModerate
Intervention NR
Composite: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · HDI: Medium
Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025)
RR 7.07 [5.33, 9.38]2 studiesUngraded
Intervention NR
Amalgam: Preference for replacement over repair - Scenario 3: secondary caries · Coverage: Covering cost of minimally invasive treatment
Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025)
RR 7.47 [5.63, 9.93]NRUngraded