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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 |
|---|---|---|---|
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 studies | Ungraded |
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 groups | 8 studies · 889 participants | Low |
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 ~2.0 | 7 studies | Ungraded |
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. | NR | Ungraded |
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 participants | Ungraded |
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 studies | Ungraded |
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 study | Ungraded |
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 studies | Low |
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 extracted | 1 study | Ungraded |
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 studies | Ungraded |
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 participants | Ungraded |
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 studies | Ungraded |
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 participants | Ungraded |
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 studies | Ungraded |
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 studies | Ungraded |
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 studies | Low |
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 1.23 | NR | Ungraded |
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 participants | Ungraded |
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 studies | Moderate |
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 participants | Ungraded |
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 study | Ungraded |
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] | NR | Ungraded |
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 extracted | 1 study | Ungraded |
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 0.80 | 3 studies | Ungraded |
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 studies | Ungraded |
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) participants | Ungraded |
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 participants | Ungraded |
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. | NR | Ungraded |
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 participants | Ungraded |
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 extracted | 0 studies | No 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 studies | Ungraded |
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] | NR | 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) 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… | NR | Ungraded |
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 studies | 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 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 studies | Ungraded |
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 studies | Ungraded |
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 participants | Ungraded |
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 77.0 | 45 studies | Ungraded |
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 49 | 49 studies | Ungraded |
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 participants | Low |
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 studies | Ungraded |
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 participants | Ungraded |
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 studies | Low |
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 association | NR | Ungraded |
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 participants | Ungraded |
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 studies | Ungraded |
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 studies | Ungraded |
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 studies | Moderate |
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 studies | Ungraded |
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] | NR | Ungraded |