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Search review questions

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
Intervention NR
Amalgam: 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 7.37 [3.51, 15.46]2 studiesUngraded
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), South Europe
Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025)
MEAN 2.61 [1.60, 3.62]12 studiesUngraded
Intervention NR
Composite: 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 2.54 [1.69, 3.81]7 studiesUngraded
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) · By region: East Asia
Multimorbidity patterns of dental caries and obesity/overweight among adults: a systematic review and… (2025)
OR 1.02 [0.94, 1.11]NRUngraded
Hall technique vs Conventional restoration
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 3.66 [1.29, 10.40]44 studiesModerate
Replacement of the defective restoration vs Repair of the defective restoration
Composite: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · 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 0.37 [0.29, 0.48]21 studies · 3680 participantsUngraded
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: High
Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025)
RR 5.06 [4.22, 6.06]7 studies · 1223 participantsUngraded
E-cigarette use (ENDS / vaping) vs Non-smokers
Combined salivary proinflammatory markers (IL-1β, IL-6, IL-8, TNF-α) · 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, Saliva
The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025)
Cohen's d 0.21 [-0.36, 0.77]4 studiesUngraded
Anorexia nervosa (as exposure; diagnosed by DSM-III/III-R/IV/V) vs Healthy individuals without anorexia nervosa (age- and sex-matched controls)
Salivary pH · 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 -0.39 [-0.54, -0.24]3 studies · 180 participantsLow
Postbiotic toothpaste vs Fluoride toothpaste
Increased salivary IgA · Children aged 6-12 years · Daily for 14 days to 4 weeks
Postbiotics and Dental Caries: A Systematic Review. (2025)
Postbiotic toothpaste significantly increased salivary IgA versus fluoride toothpaste (Basir 2022); the review also cites Lin 2022 for postbiotic immune modulation/IgA; no pooled estimate.1 studyUngraded
Unemployment rate vs Not applicable
OHRQoL sum score transformed to 0-100 · Community-dwelling adults aged 60 years or older · Baseline for longitudinal studies
Association between oral health-related quality of life and structural determinants of health among elderly… (2025)
There was no statistically significant difference in OHRQoL based on unemployment rate.NRUngraded
Intervention NR
Amalgam: Preference for replacement over repair - Scenario 5: open margin · Continent: South America
Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025)
RR 5.15 [3.98, 6.66]2 studiesUngraded
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)
Hip/femoral bone mineral density (BMD) · Females (all ages) · Long-term / lifetime fluoride exposure, Females, low-to-moderate risk-of-bias studies: up to ~2.3 mg/L vs null
The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025)
MD 0.04 [-0.03, 0.12]NRUngraded
E-cigarette use (ENDS / vaping) vs Non-smokers
Untreated dental caries and caries risk · Humans who use e-cigarettes (adolescents to adults) assessed for dental caries · Cross-sectional
The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025)
Narrative synthesis (not meta-analyzed). E-cigarette users had more untreated caries and higher caries risk than non-smokers in individual studies: Vemulapalli 2021 untreated-caries OR 2.04 (non-smokers as reference);…3 studiesUngraded
Intervention NR
Amalgam: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · Coverage: Covering cost of minimally invasive treatment
Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025)
RR 4.09 [2.77, 6.04]NRUngraded
Intervention NR
Composite: 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 2.45 [1.73, 3.48]2 studiesUngraded
Intervention NR
Amalgam: Preference for replacement over repair - Scenario 6: corrosion · Coverage: Not covering
Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025)
RR 1.54 [1.12, 2.12]NRUngraded
Ion-releasing restorations (IRR): RMGIC, HVGIC, GIC, compomer/PMRC, giomer vs Composite resin (CR), including bulk-fill composite
Absence of sensibility (post-operative sensitivity) · 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 1.02 [0.95, 1.11]3 studies · 197 participantsHigh
Replacement of the defective restoration vs Repair of the defective restoration
Amalgam: Preference for replacement over repair - Scenario 5: open margin · 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 5.14 [4.02, 6.57]21 studies · 3680 participantsUngraded
Self-assembling/remineralizing peptide (e.g., P11-4, PAA-PASP) vs HEMA/EGDMA-based desensitizer
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 -0.369 [-6.728, 5.990]0 studiesLow
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS
Osteoporosis · European GWAS participants · SVMR Weighted Median
From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025)
OR 1.260 [1.017, 1.560]483725 participantsUngraded
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS
Postmenopausal osteoporosis with pathological fracture · European GWAS participants · SVMR MR-Egger
From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025)
OR 1.355 [0.696, 2.635]281786 participantsUngraded
Lactobacillus-derived postbiotics vs Not specified
Streptococcus mutans growth and biofilm formation · Reference strains of Streptococcus mutans and cariogenic biofilms · 24 h to 7 days
Postbiotics and Dental Caries: A Systematic Review. (2025)
no estimate extracted12 studiesUngraded
Hall technique 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 · 12-24 months, 12-24-month follow-up
Comparative success of minimally invasive treatments for cavitated caries in primary teeth: a network… (2025)
OR 5.13 [1.18, 22.38]21 studiesModerate
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence)
Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Publication-bias adjusted (trim-and-fill)
Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025)
Prevalence 62 [58, 81]NRUngraded
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 0.25 mg/L vs null
The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025)
RR 0.98 [0.83, 1.14]NRUngraded
Early childhood caries vs Caries-free controls
Veillonella spp. relative abundance · Young children with early childhood caries and caries-free controls
A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025)
Mean relative abundance (%) ECC 3.29 (SD 6.83) vs caries-free 2.13 (SD 2.30)1 study · 87 participantsUngraded
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 · Overall (all dentition)
Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025)
Specificity 0.745 studiesUngraded
Hydroxyapatite (e.g., nano-HAp) 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 -2.916 [-5.854, 0.023]5 studiesModerate
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS
Femur fracture · European GWAS participants · SVMR Weighted Median
From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025)
OR 1.094 [0.884, 1.354]489106 participantsUngraded
quantitative light-induced fluorescence (QLF) vs reference standard
detection of occlusal caries · human primary or permanent teeth with dental caries lesions · permanent dentition
Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025)
Specificity 0.803 studiesUngraded
E-cigarette use (electronic nicotine delivery systems / vaping) vs Non-smokers (non-users)
Plaque index / oral biofilm accumulation · 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 exhibited a higher plaque index than non-smokers across included reviews (Shabil, Vamos, Youssef, Thiem, Figueredo, Yang [24,25,27,29,30,31]); the umbrella review reported no…6 studiesUngraded
Health expenditure per capita vs Higher vs lower per-capita health expenditure categories
Oral health-related quality of life (OHRQoL sum score, transformed 0-100) · Community-dwelling elderly persons aged ≥60 years · Across per-capita health expenditure categories
Association between oral health-related quality of life and structural determinants of health among elderly… (2025)
No statistically significant difference in OHRQoL based on per-capita health expenditure (Fig. 3a).NRUngraded
Intervention NR
Composite: 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 1.66 [1.09, 2.54]6 studiesUngraded
Intervention NR
Composite: 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 0.85 [0.72, 1.00]7 studiesUngraded
Nocturnal (night) feeding vs No nocturnal 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 2.417 [1.340, 4.358]1 studyUngraded
Electronic cigarette use vs Non-smokers
DMFT/DMFS score · 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 0.93 [-1.11, 2.98]3 studiesUngraded
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), >$100 per capita
Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025)
MEAN 0.96 [0.64, 1.28]12 studiesUngraded
Intervention NR
Early childhood caries (ECC), prevalence · Study design: school-based
Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025)
Prevalence 55 [44, 67]9 studiesUngraded
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability
Lumbar spine bone mineral density · European GWAS participants · SVMR IVW
From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025)
BETA 0.055 [0.008, 0.102]28498 participantsUngraded
Intervention NR
Log diagnostic odds ratio · Imaging modality: Periapical radiographs
Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025)
Log DOR 4.72 [3.16, 6.27]12 studiesUngraded
Replacement of the defective restoration vs Repair of the defective restoration
Composite: Preference for replacement over repair - Scenario 3: secondary caries · 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), Continent: South America
Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025)
RR 1.33 [1.03, 1.71]2 studies · 349 participantsUngraded
HEMA/EGDMA-based desensitizer vs Calcium phosphate agent (e.g., CPP-ACP, Ca/P-PILP, niobophosphate)
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 0.360 [-5.589, 6.309]0 studiesModerate
School-based supervised toothbrushing (STB) vs No intervention
Dental caries increment, DMFS/dmfs (tooth-surface level) · Children in school or kindergarten settings (aged 3-14 years) · 2-3 years follow-up
The effectiveness of school-based supervised tooth brushing intervention for preventing dental caries: a… (2025)
SMD -0.22 [-0.42, -0.01]3 studies · 1135 participantsUngraded
E-cigarette use (ENDS / vaping) vs Non-smokers
Interleukin-1 beta (IL-1β) · 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 0.98 [-0.03, 1.99]11 studiesUngraded
Intervention NR
Clinical and radiographic success rate · Full meta-regression: follow-up duration
Partial pulpotomy for carious pulp exposure in adult mature permanent teeth: a systematic review and… (2025)
Meta-regression No significant associationNRUngraded
Inactivated-bacteria tablets vs Not specified
Caries prognosis and oral-microbiota diversity structure and function · Patients after dental filling · 14 days
Postbiotics and Dental Caries: A Systematic Review. (2025)
no estimate extracted1 studyUngraded
Hydroxyapatite (e.g., nano-HAp) 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 4.960 [-1.806, 11.727]0 studiesLow
Intervention NR
Log diagnostic odds ratio (trim-and-fill adjusted for publication bias) · Overall; trim-and-fill (20 observed + 6 imputed studies)
Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025)
Log DOR 3.913 [3.219, 4.606]26 studiesUngraded
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: Low
Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025)
RR 3.39 [2.18, 5.27]2 studies · 350 participantsUngraded