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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
Intervention NR
Marginal integrity success rate · Study design: Randomized controlled trial
Success rate of proximal tooth-coloured direct restorations in primary teeth at 24 months: a meta-analysis. (2020)
Proportion 0.907 [0.838, 0.948]13 studiesUngraded
Tooth-coloured direct restorative materials (composite, compomer, giomer, RMGIC, HVGIC, open-sandwich) vs No comparator group (single-arm pooled success rate; materials/techniques contrasted via moderator analyses)
Absence of recurrent caries success rate · Children with primary molars requiring proximal (Class II) restorations · 24 months
Success rate of proximal tooth-coloured direct restorations in primary teeth at 24 months: a meta-analysis. (2020)
Proportion 0.909 [0.865, 0.939]30 studiesUngraded
Tooth-coloured direct restorative materials (composite, compomer, giomer, RMGIC, HVGIC, open-sandwich) vs No comparator group (single-arm pooled success rate; materials/techniques contrasted via moderator analyses)
Retention success rate · Children with primary molars requiring proximal (Class II) restorations · 24 months, Financial source: Private or mixed
Success rate of proximal tooth-coloured direct restorations in primary teeth at 24 months: a meta-analysis. (2020)
Proportion 0.807 [0.482, 0.949]5 studiesUngraded
Illicit drug use vs People who do not use drugs
Periodontal disease · People who use drugs (PWUD): methamphetamine, heroin, opiate, cannabis and cocaine users
Dental caries and periodontal disease among people who use drugs: a systematic review and meta-analysis. (2020)
OR 1.44 [0.80, 2.60]5 studiesUngraded
Laser fluorescence (DIAGNOdent and DIAGNOdent pen) vs Reference standard: histology (in vitro studies) or visual-tactile examination (in vivo studies)
Sensitivity · Adults presenting asymptomatically or suspected of having root caries (in vivo studies); extracted teeth of adults (in…
Tests to detect and inform the diagnosis of root caries (2020) · Cochrane
4 studies (4997 root surfaces) investigated laser fluorescence and reported estimates of sensitivity ranging from 0.50 to 0.81 and specificity ranging from 0.40 to 0.80. 2 studies evaluated tests on in vivo primary…4 studiesVery low
Resin-based fissure sealant (visible-light-polymerized) vs Fluoride varnish
Incidence of dentinal carious lesion on treated occlusal surfaces of molars or premolars (yes/no) · Children and adolescents from the general population, younger than 20 years of age at the start of the study · 4 years
Pit and fissure sealants versus fluoride varnishes for preventing dental decay in the permanent teeth of… (2020) · Cochrane
RR 0.42 [0.21, 0.84]1 study · 75 participantsVery low
TT genotype of AMELX rs2106416 vs CC + CT genotype of AMELX rs2106416
Dental caries susceptibility · Individuals assessed for dental caries (cases with caries/high caries vs. caries-free or low/very-low-caries controls) · Age group: Children
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 1.67 [0.44, 6.34]3 studiesUngraded
All fluorescence-based devices (red, blue, and green fluorescence combined) vs Reference standard: histology, enhanced visual examination with or without radiographs, or excavation
Diagnostic odds ratio (DOR) by subgroup: Proximal surfaces (detection of early enamel caries, D1 threshold) · Children or adults presenting asymptomatically or suspected of having enamel caries (in vivo/clinical studies);… · Up to 3 months between index test and reference standard (in vivo studies), Proximal surfaces
Fluorescence devices for the detection of dental caries (2020) · Cochrane
DOR 13.06 [7.52, 22.67]NRUngraded
GG genotype of LTF rs1126478 vs AA genotype of LTF rs1126478
Dental caries susceptibility · Individuals assessed for dental caries (cases with caries/high caries vs. caries-free or low/very-low-caries controls) · Ethnicity: Caucasian
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 1.49 [0.58, 3.85]2 studiesUngraded
CT genotype of AMELX rs6639060 vs CC genotype of AMELX rs6639060
Dental caries susceptibility · Individuals assessed for dental caries (cases with caries/high caries vs. caries-free or low/very-low-caries controls) · Overall
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 1.27 [0.49, 3.30]2 studies · 301 participantsUngraded
AMELX rs2106416 CT + TT genotype vs CC genotype
Dental caries susceptibility · Individuals with caries/high caries and caries-free or low-caries controls · Overall (n=3)
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 0.59 [0.15, 2.31]3 studies · 285 participantsUngraded
Vegetarian diet (any diet excluding all meat, poultry and fish) vs Nonvegetarian diet
Dental caries (mean DMFT score) · General population (children and adults) assessed for dental hard-tissue health
Vegetarian diet and its possible influence on dental health: A systematic literature review. (2020)
MD -0.15 [-0.29, -0.02]4 studiesUngraded
GG genotype of ENAM rs1264848 vs AA + AG genotype of ENAM rs1264848
Dental caries susceptibility · Individuals assessed for dental caries (cases with caries/high caries vs. caries-free or low/very-low-caries controls) · Age group: Children
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 0.66 [0.37, 1.17]4 studiesUngraded
CT + TT genotype (T-allele carriers) of AMELX rs17878486 vs CC genotype of AMELX rs17878486
Dental caries susceptibility · Individuals assessed for dental caries (cases with caries/high caries vs. caries-free or low/very-low-caries controls) · Ethnicity: Caucasian
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 2.03 [0.10, 42.44]2 studiesUngraded
TT genotype of AMELX rs2106416 vs CC + CT genotype of AMELX rs2106416
Dental caries susceptibility · Individuals assessed for dental caries (cases with caries/high caries vs. caries-free or low/very-low-caries controls) · Overall
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 1.67 [0.44, 6.34]3 studies · 285 participantsUngraded
TT genotype of ENAM rs3796703 vs CC + CT genotype of ENAM rs3796703
Dental caries susceptibility · Individuals assessed for dental caries (cases with caries/high caries vs. caries-free or low/very-low-caries controls) · Age group: Children
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 2.90 [0.92, 9.12]2 studiesUngraded
G allele of ENAM rs3796704 vs A allele of ENAM rs3796704
Dental caries susceptibility · Individuals assessed for dental caries (cases with caries/high caries vs. caries-free or low/very-low-caries controls) · Age group: Children
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 1.46 [0.92, 2.32]2 studiesUngraded
Tooth-coloured direct restorative materials (composite, compomer, giomer, RMGIC, HVGIC, open-sandwich) vs No comparator group (single-arm pooled success rate; materials/techniques contrasted via moderator analyses)
Retention success rate · Children with primary molars requiring proximal (Class II) restorations · 24 months, Financial source: Public
Success rate of proximal tooth-coloured direct restorations in primary teeth at 24 months: a meta-analysis. (2020)
Proportion 0.909 [0.785, 0.965]12 studiesUngraded
GG genotype of ENAM rs1264848 vs AA + AG genotype of ENAM rs1264848
Dental caries susceptibility · Individuals assessed for dental caries (cases with caries/high caries vs. caries-free or low/very-low-caries controls) · Ethnicity: Caucasian
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 0.76 [0.34, 1.72]4 studiesUngraded
AG + GG genotype (G-allele carriers) of ENAM rs1264848 vs AA genotype of ENAM rs1264848
Dental caries susceptibility · Individuals assessed for dental caries (cases with caries/high caries vs. caries-free or low/very-low-caries controls) · Overall
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 1.24 [0.93, 1.67]5 studies · 1534 participantsUngraded
All fluorescence-based devices (red, blue, and green fluorescence combined) vs Reference standard: histology, enhanced visual examination with or without radiographs, or excavation
Diagnostic odds ratio (DOR) by subgroup: Occlusal surfaces (detection of early enamel caries, D1 threshold) · Children or adults presenting asymptomatically or suspected of having enamel caries (in vivo/clinical studies);… · Up to 3 months between index test and reference standard (in vivo studies), Occlusal surfaces
Fluorescence devices for the detection of dental caries (2020) · Cochrane
DOR 14.29 [10.92, 18.72]NRUngraded
Intervention NR
Dental caries in permanent teeth · Children (permanent dentition) worldwide · America
Dental caries in primary and permanent teeth in children's worldwide, 1995 to 2019: a systematic review and… (2020)
Prevalence 0.489 [0.376, 0.603]7 studies · 5009 participantsUngraded
Resin-based fissure sealant vs Fluoride varnish
Dentine caries in permanent molars (yes/no) · Children and adolescents from the general population, younger than 20 years of age at the start of the study · 2-3 years
Pit and fissure sealants versus fluoride varnishes for preventing dental decay in the permanent teeth of… (2020) · Cochrane
OR 0.67 [0.37, 1.19]4 studies · 1683 participantsVery low
AG genotype of ENAM rs1264848 vs AA genotype of ENAM rs1264848
Dental caries susceptibility · Individuals assessed for dental caries (cases with caries/high caries vs. caries-free or low/very-low-caries controls) · Age group: Children
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 1.30 [0.84, 2.01]4 studiesUngraded
Intervention NR
Absence of recurrent caries success rate · Random assignment: Correct
Success rate of proximal tooth-coloured direct restorations in primary teeth at 24 months: a meta-analysis. (2020)
Proportion 0.914 [0.849, 0.953]15 studiesUngraded
LTF rs1126478 AG genotype vs AA genotype
Dental caries susceptibility · Individuals with caries/high caries and caries-free or low-caries controls · Overall (n=4)
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 1.00 [0.80, 1.25]4 studies · 2662 participantsUngraded
LTF rs2073495 variant vs Reference allele/genotype
Dental caries · Human subjects with dental caries and caries-free controls · Single study (Doetzer et al. 2015)
The association between genetic variants in lactotransferrin and dental caries: a meta- and gene-based… (2020)
OR 0.99 [0.86, 1.15]1 study · 677 participantsUngraded
G allele of ENAM rs1264848 vs A allele of ENAM rs1264848
Dental caries susceptibility · Individuals assessed for dental caries (cases with caries/high caries vs. caries-free or low/very-low-caries controls) · Ethnicity: Mixed
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 1.23 [0.79, 1.91]1 studyUngraded
Intervention NR
Dental caries in permanent teeth · Children (permanent dentition) worldwide · Asia
Dental caries in primary and permanent teeth in children's worldwide, 1995 to 2019: a systematic review and… (2020)
Prevalence 0.588 [0.534, 0.64]50 studies · 1334133 participantsUngraded
CT + TT genotype (T-allele carriers) of AMELX rs946252 vs CC genotype of AMELX rs946252
Dental caries susceptibility · Individuals assessed for dental caries (cases with caries/high caries vs. caries-free or low/very-low-caries controls) · Control group: Low caries
Association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility: a meta-analysis. (2020)
OR 0.98 [0.46, 2.07]1 studyUngraded
Pulpotomy vs Pulpectomy
Tooth survival · Children with carious vital pulp exposure in primary incisors · 18-24 months
Pulpotomy versus pulpectomy in the treatment of vital pulp exposure in primary incisors. A systematic review… (2019)
Survival rate 0.94 (95% CI 0.89 to 0.97) for pulpotomy and 0.97 for pulpectomy at 18 months (Nguyen et al.); 63% for pulpotomy and 85% for pulpectomy at 2 years (Casas et al.). Not pooled.2 studiesUngraded
Longitudinal follow-up over time (natural caries progression; no assigned intervention) vs Within-cohort change from baseline to follow-up (>=3 y)
Annual decline in percentage of caries-free participants (permanent dentition, D3) · Children and adolescents (permanent dentition, D3, up to 21 y), Western or comparable populations · Annual (studies with >=3 y follow-up), Baseline caries experience: low
Caries Progression Rates Revisited: A Systematic Review. (2019)
4.3% to 10.2%9 studies · 4811 participantsUngraded
Rubber/elastomeric cleaning stick plus toothbrushing vs Toothbrushing alone
Gingivitis (proportion of bleeding sites) · Adults, 16 years and older (dentate) · 1 month
Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane
MD -0.07 [-0.15, 0.01]1 study · 30 participantsVery low
Residence in heavily contaminated area (approx. 15-40 Ci/km2) vs Residence in non-contaminated (non-exposed) area (<1 Ci/km2)
Dental caries experience (DMFT/dmft index) · Children aged 12-15 years (adolescents) · heavy contamination
A systematic review of the caries prevalence among children living in Chernobyl fallout countries. (2019)
WMD 1.06 [0.92, 1.20]1 study · 143 participantsUngraded
Sealant vs No treatment
Arrest or reversal of noncavitated approximal carious lesions · Children and adults with noncavitated carious lesions on approximal surfaces (primary and permanent teeth) · 12-36 mo
Nonrestorative Treatments for Caries: Systematic Review and Network Meta-analysis. (2019)
RR 2.41 [1.26, 4.58]6 studies · 565 participantsLow
440 to 550 ppm F toothpaste vs Non-fluoride (0 ppm F) placebo toothpaste
Caries increment, tooth index D(M)FT · Children and adolescents with immature permanent dentition (aged 5 to 16 years at study start) · Closest to 36 months
Fluoride toothpastes of different concentrations for preventing dental caries (2019) · Cochrane
SMD -0.18 [-0.41, 0.04]2 studiesLow
Colour clinical examination (visual shade categorization: yellow, light brown, dark brown, black) vs Hardness clinical examination (tactile texture categorization: soft, medium/leathery, hard)
Discriminant power for caries severity: effect size (f) for microbial load (log10 CFU) between lesion categories · Patients with dentine carious lesions (deciduous/permanent teeth; children and adults)
Reliability of colour and hardness clinical examinations in detecting dentine caries severity: a systematic… (2019)
Effect size (f) colour f=0.46; hardness f=2.625 studiesUngraded
1000 to 1250 ppm F toothpaste vs 250 ppm F toothpaste
Caries increment, surface index D(M)FS · Children and adolescents with immature permanent dentition (aged 5 to 16 years at study start) · Closest to 36 months
Fluoride toothpastes of different concentrations for preventing dental caries (2019) · Cochrane
SMD -0.14 [-0.24, -0.04]7 studiesLow
Residence in weakly contaminated area (approx. 1-5 Ci/km2) vs Residence in non-contaminated (non-exposed) area (<1 Ci/km2)
Dental caries experience (DMFT/dmft index) · Children aged 5-7 years (early school-age) · weak contamination
A systematic review of the caries prevalence among children living in Chernobyl fallout countries. (2019)
WMD 0.45 [0.32, 0.58]1 study · 117 participantsUngraded
1450 ppm F toothpaste vs 250 ppm F toothpaste
Caries increment, tooth index d(m)ft · Young children with primary (deciduous) dentition (aged 1 to 6 years at study start) · Follow-up: 22 months
Fluoride toothpastes of different concentrations for preventing dental caries (2019) · Cochrane
MD -0.4 [-1.14, 0.34]1 study · 172 participantsLow
Rubber/elastomeric cleaning stick plus toothbrushing vs Flossing plus toothbrushing
Plaque · Adults, 16 years and older (dentate) · 4 to 6 weeks
Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane
SMD -0.08 [-0.46, 0.29]6 studies · 273 participantsVery low
Longer follow-up vs Shorter follow-up
Annual increment in DMFS (D3) · Children and adolescents with permanent dentition · Per additional year of follow-up, Not adjusted
Caries Progression Rates Revisited: A Systematic Review. (2019)
Meta-regression beta per year of follow-up 0.43 [0.04, 0.83]22 studies · 11300 participantsUngraded
Flossing plus toothbrushing vs Toothbrushing alone
Interproximal caries · Adults, 16 years and older (dentate)
Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane
No included study assessed caries as an outcome.0 studiesNo studies
1000 to 1250 ppm F toothpaste vs 440 to 550 ppm F toothpaste
Caries increment, tooth index D(M)FT · Children and adolescents with immature permanent dentition (aged 5 to 16 years at study start) · Closest to 36 months
Fluoride toothpastes of different concentrations for preventing dental caries (2019) · Cochrane
SMD -0.08 [-0.3, 0.15]1 studyLow
38% SDF solution (applied biannually) vs 12% SDF solution (applied biannually)
Arrest of advanced cavitated carious lesions on any coronal surface · Preschool children with advanced cavitated carious lesions on any coronal surface (primary teeth) · 12 mo
Nonrestorative Treatments for Caries: Systematic Review and Network Meta-analysis. (2019)
RR 1.3 [1.21, 1.41]1 study · 799 participantsHigh
Dental cavity liner (e.g. calcium hydroxide, glass ionomer, resin-modified glass ionomer, or flowable composite) placed under the restoration vs No liner (resin-based composite bonded directly to the tooth)
Postoperative hypersensitivity (POH), patient-reported (dichotomous yes/no) · Adults or children with a Class I or Class II resin-based composite restoration in a permanent posterior tooth · 1 week
Dental cavity liners for Class I and Class II resin‐based composite restorations (2019) · Cochrane
RR 0.56 [0.26, 1.17]3 studiesLow
1450 ppm F toothpaste vs 250 ppm F toothpaste
Caries increment, surface index d(m)fs · Young children with primary (deciduous) dentition (aged 1 to 6 years at study start) · Follow-up: 22 months
Fluoride toothpastes of different concentrations for preventing dental caries (2019) · Cochrane
MD -1.2 [-2.92, 0.52]1 study · 172 participantsLow
1000 or 1100 ppm F toothpaste vs Non-fluoride (0 ppm F) placebo toothpaste
Caries increment, tooth index DMFT · Adults with mature permanent dentition (aged 18 to 93 years at study start) · 24 months
Fluoride toothpastes of different concentrations for preventing dental caries (2019) · Cochrane
MD -0.46 [-0.93, 0.01]1 study · 247 participantsLow
12,500 ppm F (NaF/olaflur/dectaflur) amine fluoride gel vs 0 ppm F placebo gel
Number of participants with more severe DLs (severity of DLs) · Orthodontic patients of any age with fixed braces (new DLs assessed at debond) · At debond (end of orthodontic treatment)
Fluorides for preventing early tooth decay (demineralised lesions) during fixed brace treatment (2019) · Cochrane
Additional SoF Table 1. Number of participants with more severe DLs: none of the trials reported this outcome.0 studiesNo studies
Wooden cleaning stick plus toothbrushing vs Flossing plus toothbrushing
Periodontitis (probing pocket depth) · Adults, 16 years and older (dentate)
Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane
No included study assessed periodontitis.0 studiesNo studies