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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.
5,762 questions in 263 reviews · Dental caries
current versionsNo studies 321 · 5.6%Ungraded 4,450 · 77.2%Very low 455 · 7.9%Low 297 · 5.2%Moderate 200 · 3.5%High 39 · 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 |
|---|---|---|---|
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of fragility fractures · Females aged over 50 years · Long-term / lifetime fluoride exposure, Females over 50 years: drinking-water fluoride 1.0 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 1.26 [1.10, 1.46] | NR | Ungraded |
Intervention NR Postoperative hypersensitivity · TheraCal LC vs Dycal (Bayoumy et al.) Efficacy of different cavity liners compared to no cavity lining in managing deep caries in vital permanent… (2025) | Patients pain-free at 12 months 100% (TheraCal) vs 81% (Dycal); p<0.05 | 1 study | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Lumbar spine bone mineral density (BMD) · General population (both sexes, all ages) · Long-term / lifetime fluoride exposure, Sensitivity (excluding high risk-of-bias studies): above 2.27 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | MD 0.04 [-0.21, 0.30] | NR | 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 1.5 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 0.84 [0.43, 1.65] | NR | Ungraded |
Higher per-capita expenditure on dental health care vs Lower per-capita expenditure on dental health care (USD bands: $0-50 / $51-100 / >$100) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), $51-100 per capita Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 2.14 [1.40, 2.89] | 6 studies | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Forearm fracture · European GWAS participants · SVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.994 [0.948, 1.042] | 490889 participants | Ungraded |
Late tooth brushing initiation (>=12 months, or >=2 years in some studies) vs Early tooth brushing initiation (<12 months, or <2 years) Early childhood caries (presence/prevalence/severity by dmft/dmfs) · Healthy children under 6 years of age (6 months to 6 years); preschool children · Primary analysis (all 10 studies) Optimal tooth brushing initiation age and frequency for preventing early childhood caries: a systematic… (2025) | OR 1.40 [0.91, 2.16] | 10 studies · 23200 participants | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 3: secondary caries · Coverage: Not covering Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 2.53 [1.70, 3.78] | NR | Ungraded |
Partial pulpotomy vs Full (complete) pulpotomy Pulp sensibility (EPT/cold response) · Mature permanent (molar) teeth with deep caries and symptoms indicative of irreversible pulpitis (spontaneous pain) · 1 year The effectiveness of partial pulpotomy compared with full pulpotomy in managing deep caries in vital… (2025) | Jassal: positive pulp sensibility at 1 year - EPT positive in PP 95.45% (21/22) vs FP 63.6% (14/22); cold test positive in PP 45.45% (10/22) vs FP 13.63% (3/22). Sensibility was not used to ascertain the success… | 1 study · 44 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 · Country: Egypt Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 62 [53, 70] | 10 studies | Ungraded |
Intervention NR Specificity · Imaging modality: Intraoral photographic images Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Specificity 0.84 [0.77, 0.91] | 7 studies | 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 · Overall (all included studies) Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 57 [50, 64] | 18 studies · 11319 participants | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 6: corrosion · Continent: Europe Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.28 [0.91, 1.81] | 6 studies | Ungraded |
Secondary (passive/secondhand) smoking exposure during childhood vs No secondary smoking exposure Caries incidence (early childhood caries) · Preschool children aged <=71 months (caries outcome assessed at 3-6 years) · Caries incidence by age 3 years (exposure from infancy, 4-18 months), Overall Secondary Smoking and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2025) | RR 1.45 [1.41, 1.49] | 2 studies · 102,830 participants | Low |
Obesity or overweight (higher BMI, mostly WHO BMI ≥25/≥30; 2 studies used waist circumference) vs Normal weight (not overweight or obese) Dental caries (study-defined binary; assessed by DMFT, number of dental caries, or dentist diagnosis) · Adults (≥18 years) Multimorbidity patterns of dental caries and obesity/overweight among adults: a systematic review and… (2025) | OR 1.06 [0.98, 1.14] | 18 studies · 270408 participants | Ungraded |
Feeding on demand vs Scheduled feeding 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 9.66 [4.26, 21.93] | 1 study | Ungraded |
Country-level income inequality (Gini index) vs Lower vs higher income inequality categories Oral health-related quality of life (OHRQoL sum score, transformed 0-100) · Community-dwelling elderly persons aged ≥60 years · Adequate equality Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | MEAN 75.4 [70.1, 82.7] | NR | Ungraded |
Intervention NR Sensitivity · Imaging modality: Panoramic radiographs Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Sensitivity 0.83 [0.72, 0.94] | 8 studies | Ungraded |
Intervention NR Plaque index, e-cigarette users versus non-smokers: no significant difference (contrary/null finding) · Ralho (6 of 8 studies); Thiem (1 study) An Umbrella Review of E-Cigarettes' Impact on Oral Microbiota and Biofilm Buildup. (2025) | Qualitative (narrative synthesis) No significant plaque-index difference vs non-smokers | 2 studies | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Femur fracture · European GWAS participants · SVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.063 [0.991, 1.140] | 489106 participants | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 4: marginal discoloration · HDI: Very high Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.82 [1.34, 2.46] | 10 studies | Ungraded |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Bleeding Index (BI) · Individuals assessed for periodontal health (mainly children and adolescents, age >2 years) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | the bleeding index (BI) showed significantly higher values for subjects with cleft lip and/or palate (BI p < 0.0001) | NR | Ungraded |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Oral microbiota composition · Individuals assessed for oral microbiota (mainly children and adolescents) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | no estimate extracted | 8 studies | Ungraded |
Microinvasive techniques (resin infiltration, sealant, glass ionomer) vs Invasive treatment (conventional restorations) Radiographic progression of proximal caries lesions · Children and adults with non-cavitated proximal (interproximal) caries lesions in primary and/or permanent teeth (ages… Microinvasive interventions in the management of proximal caries lesions in primary and permanent teeth-… (2025) | no estimate extracted | 0 studies | No studies |
Male sex vs Female sex 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 2.911 [1.42, 5.99] | 1 study | 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), Overall (all 21 countries pooled) Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 3.94 [2.93, 5.31] | 21 studies · 3680 participants | Ungraded |
Late tooth brushing initiation (>=12 months, or >=2 years in some studies) vs Early tooth brushing initiation (<12 months, or <2 years) 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 (Wagner 2017 outlier excluded, k=9) Optimal tooth brushing initiation age and frequency for preventing early childhood caries: a systematic… (2025) | OR 1.75 [1.50, 2.03] | 9 studies | Ungraded |
Hall technique vs Sodium fluoride varnish (NaF) 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 8.19 [1.44, 46.63] | 44 studies | Moderate |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) Postmenopausal osteoporosis with pathological fracture · Postmenopausal women (European ancestry) · Lifelong genetic liability, SVMR (IVW), total causal effect From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.014 [0.857, 1.199] | 281786 participants | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of hip fractures · General population (both sexes, all ages) · Long-term / lifetime fluoride exposure, Overall dose-response (0 to highest exposure) The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | Curve indicated little association and was nearly flat, with a comparatively narrow 95% confidence band (no numeric RR reported in text) | NR | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · Continent: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 8.67 [5.32, 14.13] | 11 studies | Ungraded |
Epilepsy (exposure) vs Healthy participants dmft index (primary teeth) · Children or adolescents with epilepsy · Children or adolescents Evaluating the DMFT and dmft indices in people with epilepsy: A systematic review and meta-analysis. (2025) | SMD 0.132 [-0.220, 0.484] | NR | 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 Effectiveness of calcium hydroxide compared to hydraulic calcium silicate cements for direct pulp capping in… (2025) | OR 2.68 [1.7, 4.22] | 5 studies · 552 participants | Moderate |
Intervention NR Composite: 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 2.28 [1.69, 3.08] | NR | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 5: open margin · HDI: High Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 6.16 [5.32, 7.14] | 7 studies | 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 proximal (interdental) caries lesions from bitewing radiographs · Children, adolescents and adults undergoing fixed (multi-bracket) orthodontic treatment · At debonding (~23-24 months) Fluoride mouthrinses for prevention of initial caries in orthodontic patients - a systematic review and… (2025) | In one study assessments of proximal caries incidence were made as well [18]. However, just the data on the incidence of white spot lesions was included in our meta-analysis as different endpoints for the assessments… | 1 study | Ungraded |
Lacunar stroke (cases) vs Without lacunar stroke (controls) Periodontal inflamed surface area (PISA) · Adults The contribution of oral infectious diseases in lacunar stroke based on meta-analysis and Mendelian… (2025) | MD 849.92 [698.86, 1000.98] | 2 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 4: marginal discoloration · Continent: Europe Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 6.88 [4.77, 9.92] | 6 studies | Ungraded |
Postbiotics from Lactobacillus spp. (cell-free supernatants, biosurfactants, lipoteichoic acid, bacterial lysates) vs Untreated control Reduced enamel demineralization · Cariogenic bacteria (mainly Streptococcus mutans reference strains) and oral biofilms in vitro · Exposure 24 h to 7 days Postbiotics and Dental Caries: A Systematic Review. (2025) | One in vitro multispecies-biofilm study reported that a postbiotic (L. reuteri cell-free supernatant) reduced enamel demineralization, indicating a protective effect against caries; no pooled estimate. | 1 study | Ungraded |
Children with dental caries vs Children without dental caries (caries-free) Serum ferritin level · 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) | MD -3.96 [-8.48, 0.57] | 4 studies | Very low |
Intervention NR Composite: Preference for replacement over repair - Scenario 4: marginal discoloration · Continent: South America Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.44 [0.71, 2.91] | 2 studies | Ungraded |
Hydroxyapatite (e.g., nano-HAp) vs Mesoporous silica (SiO2) 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 -3.756 [-10.536, 3.024] | 0 studies | Moderate |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability, adjusted for DMFS Osteoporosis · European GWAS participants · MVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.005 [0.940, 1.074] | 483725 participants | Ungraded |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) Fracture of femur · 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 1.069 [0.923, 1.239] | 489106 participants | Ungraded |
Flavonoids (e.g., quercetin, proanthocyanidin) 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 4.604 [-2.011, 11.219] | 1 study | Moderate |
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 · Highest out-of-pocket expenditure Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | MEAN 67.5 [58.5, 76.5] | NR | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · Continent: South America Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 2.12 [0.66, 6.82] | 2 studies | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS, adjusted for periodontitis Lumbar spine and pelvis fracture · European GWAS participants · MVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.034 [0.769, 1.390] | 490700 participants | Ungraded |
Prior history of dental visit vs No prior dental visit 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 2.444 [1.108, 2.072] | 1 study | Ungraded |
Lactobacillus-derived postbiotics vs Not specified Virulence-gene expression related to adhesion acid production and exopolysaccharide synthesis · Reference strains of Streptococcus mutans and cariogenic biofilms · 24 h to 7 days Postbiotics and Dental Caries: A Systematic Review. (2025) | no estimate extracted | 7 studies | Ungraded |