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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.
10,375 questions in 429 reviews · Oral Health
current versionsNo studies 1,344 · 13%Ungraded 6,832 · 65.9%Very low 1,228 · 11.8%Low 613 · 5.9%Moderate 290 · 2.8%High 68 · 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 |
|---|---|---|---|
Intervention NR Composite: 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 4.55 [2.78, 7.45] | NR | Ungraded |
Severe early childhood caries vs Caries-free controls Veillonella dispar relative abundance · Children under 6 years with severe early childhood caries and caries-free controls A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | Median relative abundance (%) caries 3.0 (range 0.33-19.0) vs control 2.2 (0.15-9.4) | 1 study · 50 participants | Ungraded |
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), Self-Etch + chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD -2.315 [-6.066, 1.436] | 0 studies | Moderate |
Calcium phosphate vs Control Immediate (24 h) resin-dentin bond strength (MPa) · permanent human teeth with artificial caries-affected dentin · 24 h, Etch-and-Rinse; chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD -1.105 [-4.828, 2.619] | 1 study | Low |
Intervention NR Early childhood caries (ECC) - incidence/risk · Sensitivity analysis (Feldens 2010 excluded): breastfeeding >12 months Risk of Early Childhood Dental Caries Associated With Prolonged Breastfeeding: A Systematic Review and… (2025) | RR 1.37 [0.89, 2.12] | 6 studies | Ungraded |
Intervention NR Specificity · Imaging modality: Bitewing radiographs Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Specificity 0.89 [0.84, 0.95] | 5 studies | Ungraded |
Hydroxyapatite (e.g., nano-HAp) 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), Etch-and-Rinse + chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD 3.736 [-3.063, 0.536] | 0 studies | Low |
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 Adverse effects / harms (side effects) · Children, adolescents and adults undergoing fixed (multi-bracket) orthodontic treatment · During treatment Fluoride mouthrinses for prevention of initial caries in orthodontic patients - a systematic review and… (2025) | No side- or adverse effects were reported in any of the included reports. | 7 studies · 704 participants | Ungraded |
Mesoporous silica (SiO2) 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 -1.059 [-9.024, 6.906] | 0 studies | Moderate |
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 · Severe inequality Association between oral health-related quality of life and structural determinants of health among elderly… (2025) | MEAN 81.2 [75.3, 88.3] | NR | Ungraded |
Intervention NR Early childhood caries (ECC), prevalence · Study site: urban Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 59 [52, 67] | 9 studies | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Forearm fracture · European GWAS participants · SVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.883 [0.738, 1.057] | 490889 participants | Ungraded |
Calcium-based agent 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 -1.124 [-5.917, 3.670] | 2 studies | Moderate |
Older child age (months) vs Younger age (reference) Early childhood caries (ECC) · Children aged 0-5 years in North Africa · 60-71 months Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 2.845 [1.128, 2.072] | 1 study | Ungraded |
Secondary (passive/secondhand) smoking exposure during childhood vs No secondary smoking exposure Caries prevalence (early childhood caries) · Preschool children aged <=71 months (caries outcome assessed at 3-6 years) · Caries prevalence at 4-6 years, Overall Secondary Smoking and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2025) | OR 4.46 [2.08, 9.55] | 2 studies · 240 participants | Low |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · Continent: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 4.81 [3.14, 7.37] | 11 studies | Ungraded |
Heat-killed probiotic and postbiotic oral lozenges vs Placebo Salivary Streptococcus mutans count and plaque index · Adults with dental caries · 4 weeks Postbiotics and Dental Caries: A Systematic Review. (2025) | no estimate extracted | 1 study | Ungraded |
Flavonoids (e.g., quercetin, proanthocyanidin) 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 3.764 [-5.241, 12.769] | 0 studies | Moderate |
Replacement of the defective restoration vs Repair of the defective restoration Amalgam: Preference for replacement over repair - Scenario 7: non-stable (mobile) 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 24.22 [13.05, 44.95] | 21 studies · 3680 participants | Ungraded |
Having siblings vs No siblings Early childhood caries (ECC) · Children aged 0-5 years in North Africa · 1 sibling Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 3.32 [1.15, 9.54] | 1 study | Ungraded |
Replacement of the defective restoration vs Repair of the defective restoration Composite: Preference for replacement over repair - Scenario 7: non-stable (mobile) 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 12.17 [8.17, 18.11] | 21 studies · 3680 participants | Ungraded |
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: 4.0 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | MD 0.09 [-0.09, 0.27] | NR | Ungraded |
Hall technique vs Partial caries removal (PCR) 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 13.49 [1.83, 99.68] | 44 studies | Moderate |
Intervention NR Composite: Preference for replacement over repair - Scenario 6: superficial discoloration · Continent: Europe Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.20 [0.14, 0.29] | 6 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) Caries experience (DMFT index) · 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 2.00 [0.87, 3.13] | 4 studies · 406 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) · By sample size: n < 5000 Multimorbidity patterns of dental caries and obesity/overweight among adults: a systematic review and… (2025) | OR 1.13 [0.95, 1.30] | NR | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Forearm fracture · European GWAS participants · SVMR Maximum Likelihood From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.920 [0.836, 1.011] | 490889 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), Etch-and-Rinse + chemical ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD 4.333 [-5.240, 13.906] | 0 studies | Low |
Intervention NR Composite: Preference for replacement over repair - Scenario 1: partial loss or fracture of the restoration · Coverage: Not covering Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.73 [0.52, 1.03] | NR | Ungraded |
Presence of dental caries vs Adolescents without dental caries Negative oral-health impact on daily performance (OIDP or Child-OIDP) · Adolescents aged 10 to 19 years · Cross-sectional (concurrent exposure and outcome); oral impacts recalled over the prior 6 months, Caries-definition subgroup: presence of dental caries Impact of dental caries on the quality of life of adolescents: A systematic review and meta-analysis. (2025) | PR 1.19 [0.77, 1.84] | 3 studies | Ungraded |
HIV-infected children on antiretroviral therapy (HI) vs HIV-unexposed uninfected children (HUU) Dental caries (presence/absence) · Children and adolescents under 18 years with HIV · Not specified (cross-sectional), Cross-sectional studies Association between antiretroviral therapy and dental caries in children and adolescents with HIV: a… (2025) | OR 1.80 [0.98, 3.28] | NR | 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 · Overall (all dentition) Diagnostic accuracy of quantitative light-induced fluorescence in detecting caries of various types and… (2025) | Specificity 0.82 | 4 studies | Ungraded |
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), High unemployment (>10%) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 2.38 | NR | Ungraded |
Ion-releasing restorations (IRR): RMGIC, HVGIC, GIC, compomer/PMRC, giomer vs Composite resin (CR), including bulk-fill composite Adequate periodontal tissue · Children receiving dental restorations (aged 4-11 years; primary teeth; Class I/II/V cavities) · 1.5 to 2 years Clinical effectiveness of ion-releasing restorations compared to composite restorations in pediatric dental… (2025) | RR 1.13 [0.87, 1.47] | 3 studies · 231 participants | Low |
Dental treatments, care, and services (the decision context) vs None (no comparator defined) Pain 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) | 'Pain' (synonyms e.g., 'pain intensity') identified in N=49 articles (code frequency n=61); frequent in Brazil (43%), Canada (25%) and the USA (23%), not identified in Germany (0); reported across about 34 countries… | 49 studies | Ungraded |
Microinvasive techniques (resin infiltration, resin/GIC sealant, or glass ionomer varnish) vs Non-invasive measures (fluoride varnish/toothpaste, flossing, oral hygiene instruction, sham/standard of care) 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 7 years across trials), Overall (all microinvasive vs non-invasive pooled) Microinvasive interventions in the management of proximal caries lesions in primary and permanent teeth-… (2025) | OR 0.27 [0.19, 0.38] | 13 studies · 623 participants | Moderate |
Higher drinking-water fluoride concentration vs Null/reference drinking-water fluoride exposure Spine bone mineral density · Females · Females, low-to-moderate risk-of-bias studies: 0.7 to 2.35 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | MD 0.06 [-0.01, 0.12] | NR | Ungraded |
Grape seed extract (GSE) and its proanthocyanidin fractions vs Untreated or vehicle control (some studies vs positive antimicrobial controls, e.g. chlorhexidine/fluoride) Cell death / cytotoxicity · Streptococcus mutans (in vitro cultures and biofilms) Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024) | GSE showed a very low level of cell damage (<1%, few visible dead cells) (Furiga). | 1 study | Ungraded |
Prenatal vitamin D level ≤50 nmol/L vs Normal or sufficient prenatal vitamin D level Dental caries · Children aged 2 to 8 years · Maternal pregnancy to child age 2 to 8 years, Vitamin D threshold ≤50 nmol/L Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024) | OR 1.30 [1.17, 1.43] | 4 studies | Ungraded |
Experimental orthodontic composite containing nano-hydroxyapatite (n-HAP) vs Conventional/control orthodontic adhesive (e.g., Transbond XT) or negative control Superficial surface (enamel) mineralization (surface microhardness) · Human enamel specimens around orthodontic brackets (in vitro) · pH cycling 28 days, Overall Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024) | A study using an orthodontic composite containing nano-hydroxyapatite showed statistically significant remineralization compared with control orthodontic adhesives [34]. | 1 study | Ungraded |
Package of oral health education/promotion including oral hygiene advice for pregnant women, mothers, infants and young children, plus dietary and feeding practice advice for infants and young children vs Standard care Caries presence in primary teeth · For interventions, pregnant women, mothers or other caregivers of infants in the first year of life; for outcomes,… · Children assessed at 1-6 yrs Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | RR 0.73 [0.50, 1.07] | 5 studies · 1326 participants | Very low |
ADGRL2 gene (aggregate gene-based signal, MAGMA) vs Genome-wide gene background (FDR threshold) Dental caries (self-reported history) · Japanese adults (present-study direct-to-consumer genetic testing cohort); self-reported disease cases vs controls · Lifelong (germline genotype), MAGMA gene-based test (present study) Genome-wide association meta-analysis identifies two novel loci associated with dental caries. (2024) | Gene-based association analysis (MAGMA): ADGRL2 was the only gene associated with dental caries at false-discovery-rate q<0.05 (no effect size reported). | 1 study · 45525 participants | Ungraded |
Cranberry extract or cranberry flavonoid fractions vs No extract or vehicle control; other antimicrobial agents pH change or lactic acid production · Streptococcus mutans cultures and biofilms Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024) | no estimate extracted | 5 studies | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Pocket closure · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment · 3 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Three studies evaluated the proportion of closed pockets three months after treatment (Al-Zahrani 2011; Courval 2020; Rodrigues 2023); studies used different criteria to measure this outcome. All studies reported an… | 3 studies | Ungraded |
Acidic bacillary pH on teeth vs Non-acidic bacillary pH Dental caries · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 2.42 [1.494, 3.335] | NR | Ungraded |
Silver diamine fluoride (SDF; 38% in most trials, 30% in three) vs Other methods (pooled: ART/glass ionomer cement, nano-silver fluoride, placebo) Caries arrestment at the individual (patient) level · Children and adults with active dental caries (aged 1-50; mostly preschool/school children with primary dentition) · 3 weeks to 12 months, Overall (all comparators pooled) The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024) | OR 3.86 [0.34, 43.96] | 5 studies · 720 participants | Low |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Ever utilised dental services · Adult residents of slums and non-slum urban settings of LMICs · Lifetime (ever), Slum vs non-slum; urban vs rural; by sex Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | The 'ever utilised' rate ranged from 17% to 71% across studies (e.g., Osuh 17% slum vs 24% non-slum; Habib 14.6%; Hewlett 34%; Morgan 70.6%; Olusile 26%; Masalu 50% urban vs 37% rural; Singh 23% male vs 41% female). | 10 studies | Ungraded |
Stevia (high-intensity/non-nutritive sweetener) in a daily snack vs Baseline (within-group change); white sugar snack is a parallel arm with no between-group effect size reported Change in Mutans streptococci (MS) and Lactobacilli in saliva · Schoolchildren (6-9 years), high caries risk · 42 days, Single study (Cocco 2019); not pooled Clinical Effects of Sugar Substitutes on Cariogenic Bacteria: A Systematic Review and Meta-Analysis. (2024) | Cocco 2019 (the only high-intensity sweetener trial): the stevia snack showed a significant decrease in MS (P < .01) and in lactobacilli (P = .03) versus baseline, whereas the white-sugar snack showed no significant… | 1 study · 271 participants | Ungraded |
Disability (developmental, intellectual, or sensory) vs Persons without disabilities Overall oral health-related quality of life (OHRQoL) impact (self- and proxy/caregiver-reported) · Persons with disabilities (children and adults with autism, Down syndrome, cerebral palsy, hearing impairment, or… · Cross-sectional Disabilities and Disparities in Oral Health-Related Quality of Life: A Systematic Review and Meta-Analysis… (2024) | Narrative synthesis (no pooled estimate). PWDs reported reduced functional, emotional, and social well-being and greater oral-health impact on quality of life. AlJameel 2021 (Down syndrome): 34.9% of children and 46%… | NR | Ungraded |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment Hospital admission (length of stay) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | The trials did not measure hospital admission. | 0 studies | No studies |