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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.

Limit to evidence status or GRADE (optional)

5,762 questions in 263 reviews · Dental caries

current versions
No 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.

QuestionEffectEvidenceStatus / GRADE
Ion-releasing restoration, glass ionomer-based (conventional GIC, HV-GIC, RMGIC, glass hybrid) vs Resin composite restoration
Secondary caries (caries around restorations), all cavity types · Patients with permanent dentition in need of restorations (all cavity types: Black's Class I, II, V, and non-carious… · Overall (1 year, 18 months-2 years, and 3 years pooled)
Secondary caries and marginal adaptation of ion-releasing versus resin composite restorations: a systematic… (2022)
RD -0.00 [-0.01, 0.00]12 studies · 3085 participantsUngraded
Primary school-based interventions (one or more of: school health policy, oral health education, healthy school environment, access to oral health services, community involvement) vs No intervention or usual practice/activities
Oral hygiene measured by plaque scores · Primary school children (aged 3-16 years) attending primary school in low- and middle-income countries (LMICs) · Post-intervention; follow-up varied across studies (interventions ranged from <2 years to >=2 years and longer)
Effectiveness of primary school-based interventions in improving oral health of children in low- and… (2022)
SMD -0.32 [-0.46, -0.18]7 studies · 3339 participantsVery low
Genetically predicted gene expression (TWAS; S-PrediXcan with GTEx v8 cis-eQTL across 49 tissues; cross-tissue S-MultiXcan) vs ECC-unaffected children (association of genetically predicted expression)
Early childhood caries (ECC) - association with genetically predicted expression of TAS2R43 (chr12p13.2) · Children up to age 5-6 years (European / European non-Hispanic ancestry); 843 ECC-affected vs 2124 unaffected across 5… · Cross-sectional (ECC ascertained at the last dental exam before age 6), TAS2R43 (chr12p13.2); 27 (3) tissues; significant (Bonferroni p < 3.09x10-6)
Association of Early Childhood Caries with Bitter Taste Receptors: A Meta-Analysis of Genome-Wide… (2022)
Z-score (cross-tissue mean, S-MultiXcan) 1.805 studies · 2974 participantsUngraded
Intervention NR
Difference in summary sensitivity (NMA, Analysis 2) · Electrical conductance vs Fluorescence
Enamel Caries Detection and Diagnosis: An Analysis of Systematic Reviews. (2022)
Sensitivity difference (95% CrI) 0.06 [-0.09, 0.18]NRUngraded
Glass ionomer-based sealant vs Resin-based sealant (fluoride-releasing or non-fluoride-releasing)
Progression of non-cavitated enamel caries · 'Healthy' children with caries-free second primary molars, aged 3-5 years (schools and kindergartens, India and China)
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
No studies reported this outcome.0 studiesNo studies
Dental caries (carious oral microbiome) vs Caries-free / healthy oral microbiome
Differential microbial abundance / taxa predictive of caries · Individuals providing oral (saliva/supragingival plaque) 16S rRNA microbiome samples; 2016 samples from 19 studies…
Meta-analysis of caries microbiome studies can improve upon disease prediction outcomes. (2022)
Mean-decrease-accuracy discriminating taxa: Capnocytophaga HMT-338, Lactobacillus panis, Treponema HMT-230, Bifidobacterium longum, Delftia acidovorans, Staphylococcus schleiferi; higher log2FC in caries: Selenomonas HMT-146, Aggregatibacter actinomycetemcomitans, Actinomyces HMT-896, Treponema HMT-257; Streptococcus not predictive19 studies · 2016 participantsUngraded
Composite resin vs Compomer
Restoration failure · Children with carious primary teeth after vital or non-vital pulp therapy · 2 years
Clinical effectiveness of restorative materials for the restoration of carious lesions in pulp treated… (2022)
Annual failure rate (AFR, %) 01 study · 84 participantsUngraded
Fluoride-releasing resin-based sealant vs No sealant (no treatment)
Development of >=1 new carious lesion (caries incidence) · Children with caries-free or non-cavitated carious lesion primary molars, aged 3-7 years (paediatric department,… · 12 months
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
BB OR 1.21 [0.37, 3.94]1 study · 88 participantsLow
Non-responsive complementary feeding (NRCF) vs Other models of complementary feeding (responsive/traditional CF)
Weight gain (restrictive vs coercive styles) · Healthy, term-born, normal-birth-weight infants aged 4-24 months (breastfed and/or formula-fed) in Western… · Infancy to early childhood, Restrictive vs coercive/pressuring styles
Complementary Feeding Caregivers' Practices and Growth, Risk of Overweight/Obesity, and Other… (2022)
Restrictive style would favor excess weight (three of five studies); coercive style (pressure to eat) would favor a lower weight (three of five studies); clinical significance never quantified.NRUngraded
Pulpotomy (partial or full) vs None (single-arm pooled success proportion)
Clinical and radiographic success rate (>=6 months) · Human permanent teeth with irreversible pulpitis (symptomatic and asymptomatic) due to carious pulp exposure · >=6 months, Randomized trials (GRADE evidence profile)
Outcome of pulpotomy in permanent teeth with irreversible pulpitis: a systematic review and meta-analysis. (2022)
Proportion 0.743 [0.56, 0.86]5 studies · 488 participantsVery low
Intervention NR
Difference in summary specificity (NMA, Analysis 2) · Fluorescence vs Transillumination
Enamel Caries Detection and Diagnosis: An Analysis of Systematic Reviews. (2022)
Specificity difference (95% CrI) 0.01 [-0.10, 0.15]NRUngraded
Total daily fluoride intake (TDFI) and daily fluoride intake from toothpaste
Correlation between daily urinary fluoride excretion (DUFE) and fluoride intake · Children and adults with 24-h urinary fluoride monitoring (9 studies reporting both intake and urine; Table 2) · 24-h urine collection, High-fluoride-area data from Idowu et al. [46,47] excluded
Fluoride Intake Through Dental Care Products: A Systematic Review. (2022)
R2 (coefficient of determination) <0.079 studiesUngraded
Not applicable vs Not applicable
Prevalence of dental caries · Children aged 12 years (plus or minus one year) in Africa · Overall, urban/rural-status analysis
Prevalence of dental caries in the permanent dentition amongst 12-year-olds in Africa: a systematic review… (2022)
Prevalence 0.3657 [0.3065, 0.4250]NRUngraded
Intervention NR
Difference in summary sensitivity (NMA, Analysis 2) · Fluorescence vs Transillumination
Enamel Caries Detection and Diagnosis: An Analysis of Systematic Reviews. (2022)
Sensitivity difference (95% CrI) -0.01 [-0.12, 0.13]NRUngraded
Genetically predicted gene expression (TWAS; S-PrediXcan with GTEx v8 cis-eQTL across 49 tissues; cross-tissue S-MultiXcan) vs ECC-unaffected children (association of genetically predicted expression)
Early childhood caries (ECC) - association with genetically predicted expression of SMIM10L1 (chr12p13.2) · Children up to age 5-6 years (European / European non-Hispanic ancestry); 843 ECC-affected vs 2124 unaffected across 5… · Cross-sectional (ECC ascertained at the last dental exam before age 6), SMIM10L1 (chr12p13.2); 46 (3) tissues; significant (Bonferroni p < 3.09x10-6)
Association of Early Childhood Caries with Bitter Taste Receptors: A Meta-Analysis of Genome-Wide… (2022)
Z-score (cross-tissue mean, S-MultiXcan) -0.355 studies · 2974 participantsUngraded
Dental caries (carious oral microbiome) vs Caries-free / healthy oral microbiome
Alpha diversity (Chao1, Observed, Shannon) · Adults providing oral (saliva/supragingival plaque) 16S rRNA microbiome samples · Adults
Meta-analysis of caries microbiome studies can improve upon disease prediction outcomes. (2022)
In adults, there was no significant caries-vs-health difference in Chao1 or Observed diversity, whereas the Shannon index differed significantly (p < 0.001).NRUngraded
Maternal education attainment vs Children without dental caries
Dental caries (association with no formal maternal education) · Children (deciduous and/or permanent dentition) in low- and middle-income countries · No formal education
Individual, Family, and Socioeconomic Contributors to Dental Caries in Children from Low- and Middle-Income… (2022)
OR 1.34 [0.76, 2.36]3 studies · 3666 participantsUngraded
Amalgam vs Composite resin
Restoration failure · Children with carious primary teeth · 2 years, Class II
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) amalgam 17.5%; composite resin 6.2%1 study · 43 participantsUngraded
Composite resin with etch-and-rinse (total-etch) adhesion vs Composite resin with self-etch adhesion (same universal adhesive)
Treatment failure (annual failure rate) · Children with moderately deep dentine caries in primary molars, no pulp therapy · 18 months (Lenzi 2017), Adhesive strategy (etch-and-rinse vs self-etch)
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) etch-and-rinse 19.5%; self-etch 7.0%1 study · 44 participantsUngraded
Caries assessment at enamel threshold vs None
Enamel caries proportion · European adolescents aged 12 years · Exact age
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
Proportion 0.52 [0.36, 0.75]6 studiesUngraded
Amalgam restoration vs Composite resin, compomer, conventional glass-ionomer cement, or resin-modified GIC (head-to-head RCT comparators)
Treatment failure (annual failure rate) · Children with previously unrestored, vital carious lesions in primary teeth (no pulp therapy); aged 1.5-11 years · 12-60 months follow-up (4 trials; 1-5 years)
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) 1-28%4 studiesUngraded
Composite strip crown (CSC) with a post (microhybrid composite resin, Amelogen) vs Post type: composite post (CP) vs fibre post (FP) vs reverse metal post (RMP)
Treatment failure (annual failure rate) · Children with severely decayed maxillary primary incisors treated by pulpectomy (non-vital pulp therapy) · 1 year, Composite post (CP) arm
Clinical effectiveness of restorative materials for the restoration of carious lesions in pulp treated… (2022)
AFR 2.31 study · 54 participantsUngraded
Living with HIV and undergoing antiretroviral therapy (ART/HAART) vs Healthy HIV-negative controls
Dental development / dental age (mineralization chronology) · Children and adolescents (<18 years) · Cross-sectional (case-control; single time point)
Oral Health Status of Children and Adolescents Living with HIV Undergoing Antiretroviral Therapy: A… (2022)
Three studies (Fernandes 2007, de Souza 2015, Holderbaum 2005) assessed dental age (Nolla/Willems methods); Fernandes and de Souza found no significant difference between groups; Holderbaum reported mixed sex-specific…3 studiesUngraded
Resin-modified GIC vs Composite resin
Restoration failure · Children with carious primary teeth · 2 years, Class II
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) RMGIC 8.4%; composite resin 8.4%1 study · 55 participantsUngraded
Caries experience measurement (mean D(M)FS, enamel lesions included) vs None (descriptive prevalence review; subgroup analyses only)
Caries experience (mean DMFS) · European adolescents aged 12–19 years · Age group: 16–19 years
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
MEAN 7.61 [3.78, 15.30]4 studiesUngraded
Ion-releasing glass ionomer cement (GIC) restorations vs Resin composite restorations
Unacceptable marginal adaptation · Patients with permanent dentition in need of restorations · 1 year, 18 months to 2 years, and 3 years, All types of cavities
Secondary caries and marginal adaptation of ion-releasing versus resin composite restorations: a systematic… (2022)
RD 0.01 [-0.01, 0.03]9 studies · 2725 participantsUngraded
Caries assessment at dentine threshold (cavitation into dentine) vs None (descriptive prevalence review; subgroup analyses only)
Caries prevalence · European adolescents aged 12–19 years
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
Prevalence 0.56 [0.43, 0.68]15 studiesUngraded
Glass ionomer-based sealant vs No sealant
Development of >=1 new carious lesion (caries incidence) · Children with caries-free primary first molars (with or without caries on other teeth), aged 1-5 years (paediatric… · 6-12 months
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
OR 0.033 [0.007, 0.149]1 study · 107 participantsLow
Dental caries assessment (WHO/clinical diagnostic criteria; caries = DMFT>0) vs None (descriptive prevalence review; subgroup analyses by urban/rural status, country and year)
Caries prevalence · 12-year-old children (permanent dentition) in Africa · Data collection period: 2000-2004
Prevalence of dental caries in the permanent dentition amongst 12-year-olds in Africa: a systematic review… (2022)
Prevalence 0.282 [0.227, 0.337]13 studiesUngraded
Pulpotomy (partial or full) vs None (single-arm pooled success proportion)
Clinical and radiographic success rate (>=6 months) · Human permanent teeth with asymptomatic irreversible pulpitis due to carious pulp exposure · >=6 months, Asymptomatic irreversible pulpitis
Outcome of pulpotomy in permanent teeth with irreversible pulpitis: a systematic review and meta-analysis. (2022)
Proportion 0.913 [0.80, 0.965]3 studiesUngraded
Caries assessment at enamel threshold (D(M)FS>0 or D(M)FT>0, enamel lesions included) vs None (descriptive prevalence review; subgroup analyses only)
Caries prevalence · European adolescents aged 12–19 years · Region: non-Scandinavian
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
Prevalence 0.74 [0.53, 0.96]11 studiesUngraded
Pulpotomy with Biodentine vs Pulpotomy with Calcium Enriched Mixture (CEM)
Clinical and radiographic success rate (>=6 months) · Human permanent teeth with irreversible pulpitis due to carious pulp exposure · >=6 months, Pulp capping material: Biodentine vs CEM
Outcome of pulpotomy in permanent teeth with irreversible pulpitis: a systematic review and meta-analysis. (2022)
Biodentine demonstrated a statistically significantly higher success rate than CEM (indirect comparison; Supplementary Table S5, not available).NRUngraded
Pulpotomy with mineral trioxide aggregate (MTA) vs Pulpotomy with Calcium Enriched Mixture (CEM)
Clinical and radiographic success rate (>=6 months) · Human permanent teeth with irreversible pulpitis due to carious pulp exposure · >=6 months, Pulp capping material: MTA vs CEM
Outcome of pulpotomy in permanent teeth with irreversible pulpitis: a systematic review and meta-analysis. (2022)
MTA was not significantly superior to CEM (no significant difference; Supplementary Table S5, not available).NRUngraded
Caries assessment at enamel threshold vs None
Caries prevalence · European adolescents aged 12 years · Exact age
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
Prevalence 0.69 [0.49, 0.90]13 studiesUngraded
Caries assessment at dentine threshold (cavitation into dentine) vs None (descriptive prevalence review; subgroup analyses only)
Caries prevalence · European adolescents aged 12–19 years · Region: Scandinavian
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
Prevalence 0.49 [0.32, 0.67]9 studiesUngraded
Cleft lip and/or palate (CL/P) vs No cleft lip and/or palate (non-CL/P)
Caries experience in the primary dentition (dmft/dmfs/dfs/deft/ds; pooled as standardized mean difference) · Children in the primary dentition with non-syndromic cleft lip and/or palate (CL/P) and comparable children without CL/P · Primary and mixed dentition
Caries in children with and without orofacial clefting: A systematic review and meta-analysis. (2022)
SMD 0.09 [-0.59, 0.76]5 studies · 708 participantsUngraded
Transillumination and OCT vs Reference standard (histology, operative excavation, or enhanced visual examination)
Specificity for detecting enamel caries · Asymptomatic children or adults suspected of enamel caries (clinical studies); extracted teeth (in vitro studies) · Analysis 2: network meta-analysis (all studies evaluating >=2 index tests)
Enamel Caries Detection and Diagnosis: An Analysis of Systematic Reviews. (2022)
Specificity 0.82 [0.68, 0.91]64 studies · 24567 participantsLow
CD4+ T-cell count below 250 cells/mm3
HIV-related oral lesions · Children living with HIV receiving ART · CD4+ T-cell count below 250 cells/mm3
Oral Health Status of Children and Adolescents Living with HIV Undergoing Antiretroviral Therapy: A… (2022)
OR 1.916 [0.613, 2.513]1 studyUngraded
Prior application of silver diamine fluoride (SDF), with or without a rinsing step vs No prior SDF application (untreated dentin control)
Immediate bond strength (MPa) · Dental adhesives/resin composite bonded to dentin (in vitro), sound or caries-affected · Immediate bond strength, Overall (all dentin conditions and rinsing protocols)
Bonding of Glass-Ionomer Cement and Adhesives to Silver Diamine Fluoride-treated Dentin: An Updated… (2022)
MD 7.12 [1.38, 12.85]11 studies · 526 participantsUngraded
Primary school-based interventions (one or more of: school health policy, oral health education, healthy school environment, access to oral health services, community involvement) vs No intervention or usual practice/activities
Oral hygiene measured by mean gingival scores · Primary school children (aged 3-16 years) attending primary school in low- and middle-income countries (LMICs) · Post-intervention; follow-up varied across studies (interventions ranged from <2 years to >=2 years and longer)
Effectiveness of primary school-based interventions in improving oral health of children in low- and… (2022)
SMD 0.12 [-0.32, 0.55]3 studies · 1573 participantsVery low
Caries severity measurement (mean number of decayed, missing and filled permanent teeth, DMFT; WHO criteria) vs None (descriptive prevalence review; subgroup analyses by urban/rural status, country and year)
Caries severity (mean DMFT) · 12-year-old children (permanent dentition) in Africa · Country: Libya
Prevalence of dental caries in the permanent dentition amongst 12-year-olds in Africa: a systematic review… (2022)
MEAN 2.11 [1.178, 3.038]2 studiesUngraded
Primary school-based interventions (one or more of: school health policy, oral health education, healthy school environment, access to oral health services, community involvement) vs No intervention or usual practice/activities
Dental caries measured by DMFT scores · Primary school children (aged 3-16 years) attending primary school in low- and middle-income countries (LMICs) · Post-intervention; follow-up varied across studies (interventions ranged from <2 years to >=2 years and longer), Age 6-8 years
Effectiveness of primary school-based interventions in improving oral health of children in low- and… (2022)
SMD -0.11 [-0.17, -0.04]NRUngraded
Caries severity measurement (mean number of decayed, missing and filled permanent teeth, DMFT; WHO criteria) vs None (descriptive prevalence review; subgroup analyses by urban/rural status, country and year)
Caries severity (mean DMFT) · 12-year-old children (permanent dentition) in Africa · Setting: Urban
Prevalence of dental caries in the permanent dentition amongst 12-year-olds in Africa: a systematic review… (2022)
MEAN 1.325 [0.974, 1.675]10 studiesUngraded
Fluorescence-based devices vs Reference standard (histology, operative excavation, or enhanced visual examination)
Specificity for detecting enamel caries · Asymptomatic children or adults suspected of enamel caries (clinical studies); extracted teeth (in vitro studies) · Analysis 1: fully within-person comparison (studies evaluating >=3 index tests)
Enamel Caries Detection and Diagnosis: An Analysis of Systematic Reviews. (2022)
Specificity 0.88 [0.78, 0.94]19 studies · 2849 participantsUngraded
Machine-learning algorithms for dental caries detection vs Different machine-learning algorithms for caries prediction
Caries detection accuracy in unrestored molars and premolars · Dental images of human beings · Duong et al., 2021; support vector machine
Uses of Different Machine Learning Algorithms for Diagnosis of Dental Caries. (2022)
Accuracy 92.371 study · 620 participantsUngraded
Prefabricated zirconia crowns (e.g., NuSmile, Zirkiz, Kinder Krown) vs Other crowns/restorations (stainless steel crowns, pre-veneered SSC, resin composite strip crowns, glass-fiber composite crowns)
Recurrent caries (crowns free of recurrent caries) · Children with primary (deciduous) teeth requiring full-coverage crown restoration · 6 months
Zirconia Crowns for Primary Teeth: A Systematic Review and Meta-Analyses. (2022)
RR 1.00 [0.97, 1.03]2 studies · 205 participantsUngraded
Fluoride-containing dental care products (mainly fluoride toothpaste) vs Dietary fluoride sources (drinking water, beverages, food)
Contribution of dental care products to total daily fluoride intake (TDFI), by tap-water fluoride level · Adults using fluoride-containing dental care products (two included studies [28,47]; aged 20-35) · Habitual daily intake, Poor-fluoridated tap water (<0.3 mg/L)
Fluoride Intake Through Dental Care Products: A Systematic Review. (2022)
Mean contribution to TDFI (%) 121 studyUngraded
Antiretroviral therapy (any, including cART) vs No antiretroviral medication (treatment-naive)
Acute necrotising ulcerative gingivitis prevalence · Children and adolescents (<18 years) living with HIV (CLWH)
Impact of Antiretroviral Therapy on Oral Health among Children Living with HIV: A Systematic Review and… (2022)
OR 0.00 [0.00, 0.02]NRVery low
Amalgam vs Resin-modified GIC
Restoration failure · Children with carious primary teeth · 1 year, Class II
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) amalgam 28.0%; RMGIC 16.9%1 study · 120 participantsUngraded
Visual or visual-tactile classification (e.g., ICDAS, ERK) vs Reference standard (histology, operative excavation, or enhanced visual examination)
Specificity for detecting enamel caries · Asymptomatic children or adults suspected of enamel caries (clinical studies); extracted teeth (in vitro studies) · Analysis 2: network meta-analysis (all studies evaluating >=2 index tests)
Enamel Caries Detection and Diagnosis: An Analysis of Systematic Reviews. (2022)
Specificity 0.81 [0.73, 0.87]64 studies · 24567 participantsLow