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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 |
|---|---|---|---|
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), Self-Etch + chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD 2.131 [-2.213, 6.475] | 1 study | Low |
AI algorithms (predominantly CNN/deep learning) as index test vs Dental expert / visual-tactile clinical assessment (reference standard) Sensitivity · 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) | Sensitivity 0.85 [0.83, 0.93] | 20 studies · 29423 participants | Ungraded |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) Fracture of lumbar spine and pelvis · 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 0.968 [0.840, 1.114] | 490700 participants | Ungraded |
Dental caries (presence or experience) vs Adolescents without dental caries Negative oral-health impact on daily performance measured by OIDP · Adolescents aged 10 to 19 years · Cross-sectional (concurrent exposure and outcome); oral impacts recalled over the prior 6 months, Instrument subgroup: OIDP (all 3 studies) Impact of dental caries on the quality of life of adolescents: A systematic review and meta-analysis. (2025) | PR 1.68 [0.89, 3.17] | 3 studies | Ungraded |
Brushing at recommended time vs Reference brushing time Early childhood caries (ECC) · Children aged 0-5 years in North Africa Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 0.028 [0.004, 0.223] | 1 study | Ungraded |
Dental treatments including dental care and services Patients' factors of choice regarding utilization of dental treatments · 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 factors identified 101 | 233 studies | Ungraded |
Electronic cigarette use vs Non-smokers TNF-α 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 0.66 [-0.16, 1.43] | 7 studies | Ungraded |
Calcium phosphate agent (e.g., CPP-ACP, Ca/P-PILP, niobophosphate) 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), Etch-and-Rinse + chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD 0.596 [-7.289, 8.482] | 7 studies | Low |
Western/Northern Europe (UN M49 region) vs Eastern/Southern Europe (UN M49 geographical categorization) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), East Europe Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 2.76 [2.44, 3.08] | 9 studies | Ungraded |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) Fracture of forearm · 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 0.973 [0.891, 1.063] | 490889 participants | Ungraded |
Caries in mother's mouth vs No maternal caries Early childhood caries (ECC) · Children aged 0-5 years in North Africa Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 20.44 [8.37, 49.92] | 1 study | Ungraded |
Intervention NR Early childhood caries (ECC), prevalence · Study design: hospital-based Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 64 [40, 89] | 2 studies | Ungraded |
Partial pulpotomy with one additional day before permanent restoration vs Partial pulpotomy with one fewer day before permanent restoration Clinical and radiographic success rate · Adults aged 18 years or older with mature permanent teeth and carious pulp exposure · Per day of restoration delay, Meta-regression Partial pulpotomy for carious pulp exposure in adult mature permanent teeth: a systematic review and… (2025) | Meta-regression coefficient (per day, proportion scale) -0.088 | NR | Ungraded |
Iron deficiency anemia (IDA) vs Children without anemia (non-anemic) Dental caries (presence) · Children and adolescents (0-18 years; most included reviews focused on <6 years) Association Between Iron Deficiency Anemia and Dental Caries in Children: A Systematic Umbrella Meta-Analysis. (2025) | OR 3.64 [2.45, 5.40] | 3 studies | Moderate |
Spoon sharing with household members vs No spoon sharing Early childhood caries (ECC) · Children aged 0-5 years in North Africa Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 8.79 [2.92, 26.51] | 1 study | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · HDI: High Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 6.46 [5.43, 7.68] | 7 studies | Ungraded |
Conventional restoration vs Atraumatic restorative treatment (ART) 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 2.10 [1.17, 3.78] | 43 studies | Moderate |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 5: open margin · Coverage: Covering cost of minimally invasive treatment Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 4.98 [4.07, 6.09] | NR | Ungraded |
Replacement of the defective restoration vs Repair of the defective restoration Composite: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to 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 0.75 [0.62, 0.91] | 21 studies · 3680 participants | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · Continent: Africa Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.93 [0.68, 1.27] | 2 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 3: secondary caries · Continent: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 6.51 [4.64, 9.13] | 11 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 Tooth survival · 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; 99.4% survival in all groups | 12 studies · 1184 participants | Low |
Intervention NR Composite: Preference for replacement over repair - Scenario 5: open margin · HDI: Low Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.36 [0.15, 12.30] | 2 studies | Ungraded |
Replacement of the defective restoration vs Repair of the defective restoration Composite: Preference for replacement over repair - Scenario 5: open margin · 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 3.93 [2.68, 5.76] | 21 studies · 3680 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 1.1 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 1.13 [0.93, 1.37] | NR | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Femur fracture · European GWAS participants · SVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.893 [0.678, 1.175] | 489106 participants | Ungraded |
Quantitative light-induced fluorescence (QLF) vs Reference standard (histology; some ICDAS/radiography) Occlusal caries detection: sensitivity · 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) | Sensitivity 0.63 | 2 studies | Ungraded |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) 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 1.003 [0.875, 1.150] | 376746 participants | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 3: secondary caries · HDI: High Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 8.20 [6.93, 9.70] | 7 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 4: marginal discoloration · HDI: High Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 2.55 [1.79, 3.62] | 7 studies | Ungraded |
Fluoride agent (silver diamine fluoride, SDF) 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 + biological ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | Only 1 in vitro study (de Siqueira et al., 2020) assessed Self-Etch adhesive with biological ACAD; insufficient to perform a network meta-analysis, so no pooled estimate is reported. | 1 study | 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-related quality of life (OHRQoL) · Children and adolescents aged 5-18 years · Post-intervention (follow-up 0.5 to 12 months, varies by study), Overall Health promotion theory-based educational interventions for improving oral health in children and… (2025) | SMD 7.38 [5.57, 9.19] | 4 studies · 4751 participants | Low |
Dental caries (presence or experience) vs Adolescents without dental caries Negative oral-health impact on daily performance measured by OIDP · Adolescents aged 10 to 19 years · Cross-sectional (concurrent exposure and outcome); oral impacts recalled over the prior 6 months, Instrument subgroup: OIDP, sensitivity analysis excluding Krisdapong et al. Impact of dental caries on the quality of life of adolescents: A systematic review and meta-analysis. (2025) | PR 1.21 [1.15, 1.28] | 2 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 6: corrosion · HDI: Low Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.09 [0.86, 1.38] | 2 studies | Ungraded |
Ion-releasing restorations (IRR): RMGIC, HVGIC, GIC, compomer/PMRC, giomer vs Composite resin (CR), including bulk-fill composite Absence of secondary caries · 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 1.01 [0.99, 1.03] | 9 studies · 1145 participants | High |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 6: corrosion · Continent: Africa Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.60 [1.22, 2.10] | 2 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 3: secondary caries · HDI: Low Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 6.16 [4.45, 8.52] | 2 studies | Ungraded |
Biodentine (BD) vs Calcium hydroxide (CaOH) Clinical and radiographic success · Vital permanent teeth (mature or immature) with deep or extremely deep caries and asymptomatic pulp or reversible… · >=12 months Effectiveness of calcium hydroxide compared to hydraulic calcium silicate cements for direct pulp capping in… (2025) | OR 3.14 [0.91, 10.86] | 3 studies · 242 participants | Ungraded |
Postbiotic toothpaste vs Fluoride toothpaste Salivary Streptococcus mutans count · Children aged 6 to 12 years · 4 weeks Postbiotics and Dental Caries: A Systematic Review. (2025) | no estimate extracted | 1 study | Ungraded |
Hydraulic calcium silicate cements (HCSC; MTA or Biodentine) vs Calcium hydroxide (CaOH) Clinical and radiographic success · Vital permanent teeth (mature or immature) with deep or extremely deep caries and asymptomatic pulp or reversible… · 12 months, 12-month follow-up Effectiveness of calcium hydroxide compared to hydraulic calcium silicate cements for direct pulp capping in… (2025) | OR 4.44 [1.63, 12.07] | 3 studies · 174 participants | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS 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 0.867 [0.691, 1.087] | 490700 participants | Ungraded |
Replacement of the defective restoration vs Repair of the defective restoration Amalgam: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to 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), Overall (all 21 countries pooled) Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 4.70 [3.59, 6.16] | 21 studies · 3680 participants | Ungraded |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) Postmenopausal osteoporosis with pathological fracture · Postmenopausal women (European ancestry) · Lifelong genetic liability, MVMR (IVW), adjusted for periodontitis From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.422 [1.027, 1.969] | 281786 participants | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 4: marginal discoloration · Continent: Africa Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 2.88 [2.31, 3.58] | 2 studies | Ungraded |
Replacement of the defective restoration vs Repair of the defective restoration Amalgam: Preference for replacement over repair - Scenario 6: corrosion · 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 1.59 [1.24, 2.03] | 21 studies · 3680 participants | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 5: open margin · Coverage: Not covering Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 5.26 [3.58, 7.71] | NR | Ungraded |
Intervention NR Log diagnostic odds ratio · Imaging modality: Bitewing radiographs Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Log DOR 3.96 [3.20, 4.72] | 5 studies | Ungraded |
Breastfeeding for more than 24 months vs Not breastfed at the same age Prevalence of early childhood caries · Children up to 71 months · More than 24 months Risk of Early Childhood Dental Caries Associated With Prolonged Breastfeeding: A Systematic Review and… (2025) | OR 2.99 [1.03, 8.67] | 4 studies | Low |
Dental treatments, care, and services (the decision context) vs None (no comparator defined) Fear of SARS-CoV-2 infection (COVID-19) as a barrier to dental treatment · (Potential) patients with freedom of choice regarding dental treatments, including parents and caregivers deciding for… · US patients surveyed at COVID-19 onset (Papautsky et al., n=2570) Decision-making regarding dental treatments - What factors matter from patients' perspective? A systematic… (2025) | One article (Papautsky et al., US convenience sample n=2,570) reported that fear of SARS-CoV-2 infection led patients to postpone and cancel dental treatments; dental care respondents were most likely to report delays… | 1 study · 2570 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: Very high Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 6.48 [3.71, 11.31] | 10 studies · 1754 participants | Ungraded |