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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. Every word you type has to appear somewhere in the question, and the closest matches are ranked first.

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
Older age vs Younger age
Mean DMFT · School children aged 11-17 years in Sharjah · Overall
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
Regression coefficient 0.42 [0.27, 0.567]1 study · 803 participantsUngraded
Systemic sclerosis (SSc / scleroderma) vs SSc-free individuals (controls)
Bleeding on probing (BOP) · Adults (general and hospital populations assessed in case-control studies)
Oral manifestations of patients with systemic sclerosis: a meta-analysis for case-controlled studies. (2021)
SMD 1.054 [-0.973, 3.081]5 studiesUngraded
Intervention NR
Mean DMFT (decayed, missing, filled permanent teeth) · Individuals with permanent dentition in East Africa · Uganda
Prevalence of Dental Caries and Associated Factors in East Africa, 2000-2020: Systematic Review and… (2021)
MEAN 2.876 [2.186, 3.565]NRUngraded
Transillumination and optical coherence tomography devices (all illumination devices combined: NIR, OCT, and FOTI/DIFOTI) vs Reference standard: histology, or enhanced visual examination with or without radiographs (also operative excavation, tooth separation, or microcomputed tomography)
Sensitivity for detection of enamel/early caries · Children or adults presenting asymptomatically or suspected of having enamel caries (clinical/in vivo studies);… · Up to 3 months between index test and reference standard (in vivo; in vitro no limit if stored appropriately)
Transillumination and optical coherence tomography for the detection and diagnosis of enamel caries (2021) · Cochrane
Sensitivity 0.75 [0.62, 0.85]23 studiesLow
Fluoride concentration relative to the acceptable range (electrometric ion-selective electrode measurement; acceptable range mostly 0.6-0.8 ppmF) vs None (descriptive proportion meta-analysis)
Water samples with fluoride concentration above the acceptable range · Artificially fluoridated public water supply in Brazilian cities (water samples under external control) · Region: Northeast Brazil
External control of fluoridation in the public water supplies of Brazilian cities as a strategy against… (2021)
Prevalence 0.2NRUngraded
Sugar-free chewing gum (any polyol-based SFG; predominantly xylitol) vs Pooled controls: no gum, placebo/control gum, probiotic, or fluoride varnish
Streptococcus mutans load in the oral cavity (saliva and/or dental plaque) · Adults and children (general population) · Final/end-of-study time point (follow-up 2 weeks to 18 months), Overall (vs all controls)
A systematic review and meta-analysis of the role of sugar-free chewing gum on Streptococcus mutans. (2021)
SMD -0.42 [-0.60, -0.25]13 studies · 1335 participantsUngraded
Oral health knowledge, attitudes and practices assessment vs None (descriptive prevalence review)
Oral health knowledge, attitudes and practices (mothers/caregivers) · Mothers and caregivers of children in the United Arab Emirates
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
Mahmoud et al. found Sharjah mothers had higher-than-average knowledge and excellent attitudes but mostly improper practices and low dental-service utilization; knowledge/practices were associated with mothers'…NRUngraded
Dental caries (ascertained mostly by WHO criteria/DMFT; also CAST, ICDAS, or clinical examination) vs None (descriptive prevalence meta-analysis)
Dental caries prevalence · General Pakistani population (all ages and both sexes; predominantly children and adolescents) · City: Lahore
Prevalence of dental caries in Pakistan: a systematic review and meta-analysis. (2021)
Prevalence 57.604 [47.727, 67.183]4 studiesUngraded
Dental plaque assessment (plaque score/index) vs None (descriptive prevalence review)
Dental plaque levels · Children in the United Arab Emirates (Ajman, Sharjah)
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
Hashim et al. (Ajman, 5-6-year-olds) reported a mean plaque score of 0.67; higher snack consumption was associated with higher plaque (adjusted difference 0.13, 95% CI 0.02-0.24) and brushing >=twice daily with lower…NRUngraded
Observed population vs Not applicable
Molar-incisor hypomineralization prevalence · School children in Dubai governmental schools · Overall
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
Prevalence 7.591 study · 779 participantsUngraded
0-19 remaining teeth vs 20-32 remaining teeth
Atherosclerotic cardiovascular disease (ACVD)-related events (morbidity and mortality) · Adults (any age) with a known number of remaining teeth, followed prospectively in cohort studies
Lower Number of Teeth Is Related to Higher Risks for ACVD and Death-Systematic Review and Meta-Analyses of… (2021)
RR 1.98 [1.86, 2.10]4 studies · 191129 participantsModerate
Maternal smoking during pregnancy vs No maternal smoking during pregnancy
Childhood dental caries · Children in cross-sectional studies · Sensitivity: excluded Tanaka et al. 2009
Correlation Between Maternal Smoking During Pregnancy and Dental Caries in Children: A Systematic Review and… (2021)
OR 1.56 [1.46, 1.66]5 studiesUngraded
Digital bitewing radiography, sensor-based (CCD/CMOS) vs Histological validation of dental tissues (gold standard)
Diagnostic accuracy for proximal caries detection (caries detection level) · Extracted permanent posterior teeth with proximal surfaces (in vitro) · Caries detection level
Systematic review and meta-analysis of diagnostic studies of proximal surface caries. (2021)
AUC 0.7412 studiesUngraded
Visual or visual-tactile classification systems (any system: ICDAS, ERK, Nyvad, Downer, Lussi, UniViSS, or unspecified) vs Reference standard (histology, excavation, radiographs/microCT, or tooth separation)
Specificity for detection of enamel caries · Asymptomatic children or adults presenting for clinical examination (in vivo studies), or extracted teeth of children… · Up to 3 months between index test and reference standard (in vivo studies), Low prevalence of dentine caries (0% to 14%)
Visual or visual‐tactile examination to detect and inform the diagnosis of enamel caries (2021) · Cochrane
Specificity 0.73 [0.51, 0.88]NRUngraded
0-19 remaining teeth vs 20-32 remaining teeth
Atherosclerotic cardiovascular disease (ACVD)-related events (morbidity and mortality) · Adults (any age) with a known number of remaining teeth, followed prospectively in cohort studies · Multivariable-adjusted
Lower Number of Teeth Is Related to Higher Risks for ACVD and Death-Systematic Review and Meta-Analyses of… (2021)
HR 1.19 [1.13, 1.26]4 studies · 191129 participantsModerate
Radiographic imaging methods (any: analogue radiographs, digital radiographs, or CBCT) vs Reference standard (histology, excavation, or enhanced visual examination)
Specificity for detection and diagnosis of early (enamel) caries · Asymptomatic children, adolescents, or adults presenting for clinical examination (in vivo studies), or extracted… · Up to 3 months between index test and reference standard (in vivo studies), Setting: in vivo / clinical (non-CBCT)
Imaging modalities to inform the detection and diagnosis of early caries (2021) · Cochrane
Specificity 0.89 [0.78, 0.95]17 studiesUngraded
Systemic sclerosis (SSc / scleroderma) vs SSc-free individuals (controls)
Attachment loss (AL) · Adults (general and hospital populations assessed in case-control studies)
Oral manifestations of patients with systemic sclerosis: a meta-analysis for case-controlled studies. (2021)
SMD 2.584 [0.321, 4.846]4 studiesUngraded
Micro-invasive treatment (resin infiltration or sealing) vs Non-invasive / control treatment
Radiographic proximal caries lesion progression · Patients with non-cavitated proximal (approximal) caries lesions (primary or permanent dentition) · Longest available follow-up, All caries-risk levels (caries-risk subset)
Infiltration and sealing for managing non-cavitated proximal lesions: a systematic review and meta-analysis. (2021)
OR 0.20 [0.14, 0.28]9 studiesUngraded
Conventional bitewing radiography (D-speed film) vs Histological validation (serial sectioning, grinding, hemisection, or microradiography)
Diagnostic accuracy for occlusal caries detection at the dentin caries detection level (D0-2 versus D3-4) · Extracted human permanent posterior teeth (premolars and molars), occlusal (pit-and-fissure) surfaces
Systematic review and meta-analysis of diagnostic methods for occlusal surface caries. (2021)
AUC 0.601 studyUngraded
Radiographic imaging methods (any: analogue radiographs, digital radiographs, or CBCT) vs Reference standard (histology, excavation, or enhanced visual examination)
Sensitivity for detection and diagnosis of early (enamel) caries · Asymptomatic children, adolescents, or adults presenting for clinical examination (in vivo studies), or extracted… · Up to 3 months between index test and reference standard (in vivo studies), Occlusal surfaces (non-CBCT)
Imaging modalities to inform the detection and diagnosis of early caries (2021) · Cochrane
Sensitivity 0.45 [0.35, 0.54]NRUngraded
Systemic sclerosis (SSc / scleroderma) vs SSc-free individuals (controls)
Number of filled teeth · Adults (general and hospital populations assessed in case-control studies)
Oral manifestations of patients with systemic sclerosis: a meta-analysis for case-controlled studies. (2021)
SMD -0.119 [-0.302, 0.063]2 studiesUngraded
Mouth self-examination (MSE) vs Reference standard: examination and clinical evaluation by a physician/clinician with specialist knowledge or training (long-term follow-up accepted for those screened negative)
Sensitivity for detection of oral cavity cancer/OPMD · Apparently healthy adults not reporting symptoms of OPMD or OSCC, attending an organised screening or surveillance…
Clinical assessment for the detection of oral cavity cancer and potentially malignant disorders in… (2021) · Cochrane
Summary of findings 2 (no pooled analysis): sensitivity 0.18 (95% CI 0.13 to 0.24), 0.09 (95% CI 0.04 to 0.15), 0.43 (95% CI 0.24 to 0.63), and 0.33 (95% CI 0.10 to 0.65) across the 4 studies. Prevalence 0.6% to 63.6%.…4 studies · 35059 participantsVery low
TaqI (rs731236 T>C) polymorphism in the VDR gene (C allele / variant genotype) vs CT genotype vs TT genotype (heterozygous model)
Dental caries susceptibility (risk of dental caries) · Children and adults (no age limit) assessed for dental caries susceptibility · Overall
Association Between the TaqI (rs731236 T>C) Gene Polymorphism and Dental Caries Risk: A Meta-analysis. (2021)
OR 1.41 [0.89, 2.22]7 studies · 2470 participantsUngraded
Intervention NR
Mean DMFT (decayed, missing, filled permanent teeth) · Individuals with permanent dentition in East Africa · Sudan
Prevalence of Dental Caries and Associated Factors in East Africa, 2000-2020: Systematic Review and… (2021)
MEAN 3.146 [1.050, 5.242]NRUngraded
Visual or visual-tactile classification systems (any system: ICDAS, ERK, Nyvad, Downer, Lussi, UniViSS, or unspecified) vs Reference standard (histology, excavation, radiographs/microCT, or tooth separation)
Sensitivity for detection of enamel caries · Asymptomatic children or adults presenting for clinical examination (in vivo studies), or extracted teeth of children… · Up to 3 months between index test and reference standard (in vivo studies), Histology reference standard
Visual or visual‐tactile examination to detect and inform the diagnosis of enamel caries (2021) · Cochrane
Sensitivity 0.87 [0.82, 0.90]NRUngraded
Conventional bitewing radiography (D-speed film) vs Histological validation (serial sectioning, grinding, hemisection, or microradiography)
Diagnostic accuracy for occlusal caries detection at the dentin caries detection level (D0-2 versus D3-4) · Extracted human permanent posterior teeth (premolars and molars), occlusal (pit-and-fissure) surfaces
Systematic review and meta-analysis of diagnostic methods for occlusal surface caries. (2021)
Sensitivity 0.42 [0.18, 0.69]1 studyUngraded
Laser fluorescence (DIAGNOdent 2095) vs Histological validation (serial sectioning, grinding, hemisection, or microradiography)
Diagnostic accuracy for occlusal caries detection at the dentin caries detection level (D0-2 versus D3-4) · Extracted human permanent posterior teeth (premolars and molars), occlusal (pit-and-fissure) surfaces
Systematic review and meta-analysis of diagnostic methods for occlusal surface caries. (2021)
DOR 8.01 [4.04, 15.88]7 studiesUngraded
Radiographic imaging methods (any: analogue radiographs, digital radiographs, or CBCT) vs Reference standard (histology, excavation, or enhanced visual examination)
Sensitivity for detection and diagnosis of early (enamel) caries · Asymptomatic children, adolescents, or adults presenting for clinical examination (in vivo studies), or extracted… · Up to 3 months between index test and reference standard (in vivo studies), Primary dentition (non-CBCT)
Imaging modalities to inform the detection and diagnosis of early caries (2021) · Cochrane
Sensitivity 0.52 [0.40, 0.63]NRUngraded
Fibre-optic transillumination (FOTI) vs Histological validation (serial sectioning, grinding, hemisection, or microradiography)
Diagnostic accuracy for occlusal caries detection at the caries detection level (D0 versus D1-D4) · Extracted human permanent posterior teeth (premolars and molars), occlusal (pit-and-fissure) surfaces
Systematic review and meta-analysis of diagnostic methods for occlusal surface caries. (2021)
DOR 38.33 [10.15, 144.77]1 studyUngraded
TaqI (rs731236 T>C) polymorphism in the VDR gene (C allele / variant genotype) vs CT genotype vs TT genotype (heterozygous model)
Dental caries susceptibility (risk of dental caries) · Children and adults (no age limit) assessed for dental caries susceptibility · Dentition: Mixed dentition caries
Association Between the TaqI (rs731236 T>C) Gene Polymorphism and Dental Caries Risk: A Meta-analysis. (2021)
OR 1.34 [0.75, 2.40]2 studies · 270 participantsUngraded
Radiographic imaging methods (any: analogue radiographs, digital radiographs, or CBCT) vs Reference standard (histology, excavation, or enhanced visual examination)
Sensitivity for detection and diagnosis of early (enamel) caries · Asymptomatic children, adolescents, or adults presenting for clinical examination (in vivo studies), or extracted… · Up to 3 months between index test and reference standard (in vivo studies), Proximal surfaces (non-CBCT)
Imaging modalities to inform the detection and diagnosis of early caries (2021) · Cochrane
Sensitivity 0.47 [0.39, 0.55]NRUngraded
Radiographic imaging methods (any: analogue radiographs, digital radiographs, or CBCT) vs Reference standard (histology, excavation, or enhanced visual examination)
Specificity for detection and diagnosis of early (enamel) caries · Asymptomatic children, adolescents, or adults presenting for clinical examination (in vivo studies), or extracted… · Up to 3 months between index test and reference standard (in vivo studies), Reference standard: enhanced visual (non-CBCT)
Imaging modalities to inform the detection and diagnosis of early caries (2021) · Cochrane
Specificity 0.91 [0.77, 0.97]8 studiesUngraded
Fluoride concentration relative to the acceptable range (electrometric ion-selective electrode measurement; acceptable range mostly 0.6-0.8 ppmF) vs None (descriptive proportion meta-analysis)
Water samples with fluoride concentration outside the acceptable range · Artificially fluoridated public water supply in Brazilian cities (water samples under external control) · Region: Northeast Brazil
External control of fluoridation in the public water supplies of Brazilian cities as a strategy against… (2021)
Prevalence 81.1 [65.3, 92.9]NRUngraded
0-10 remaining teeth vs 25-32 remaining teeth
Atherosclerotic cardiovascular disease (ACVD)-related events (morbidity and mortality) · Adults (any age) with a known number of remaining teeth, followed prospectively in cohort studies
Lower Number of Teeth Is Related to Higher Risks for ACVD and Death-Systematic Review and Meta-Analyses of… (2021)
RR 2.65 [1.84, 3.81]4 studies · 193546 participantsHigh
Resin infiltration (Icon) vs Non-invasive treatment
Radiographic proximal caries lesion progression · Patients with non-cavitated proximal caries lesions · Longest available follow-up, Caries risk: high
Infiltration and sealing for managing non-cavitated proximal lesions: a systematic review and meta-analysis. (2021)
OR 0.14 [0.05, 0.37]2 studiesUngraded
Resin infiltration vs Untreated control (natural remineralization)
Optical/esthetic improvement (visual-tactile assessment) · Patients with post-orthodontic white spot lesions (WSL) · 4 weeks to 6 months, Modified enamel decalcification index (Cronan 2012)
Efficacy of resin infiltration to mask post-orthodontic or non-post-orthodontic white spot lesions or… (2021)
SMD 0.98 [0.83, 1.13]1 study · 768 participantsUngraded
Radiographic imaging methods (any: analogue radiographs, digital radiographs, or CBCT) vs Reference standard (histology, excavation, or enhanced visual examination)
Specificity for detection and diagnosis of early (enamel) caries · Asymptomatic children, adolescents, or adults presenting for clinical examination (in vivo studies), or extracted… · Up to 3 months between index test and reference standard (in vivo studies), Reference standard: histology (non-CBCT)
Imaging modalities to inform the detection and diagnosis of early caries (2021) · Cochrane
Specificity 0.88 [0.83, 0.92]64 studiesUngraded
Resin infiltration (Icon) vs Non-invasive treatment
Radiographic proximal caries lesion progression · Patients with non-cavitated proximal caries lesions · Longest available follow-up, Caries risk: low to moderate
Infiltration and sealing for managing non-cavitated proximal lesions: a systematic review and meta-analysis. (2021)
OR 0.38 [0.18, 0.81]1 studyUngraded
Laser fluorescence (DIAGNOdent 2190/pen) vs Direct visual examination after tooth separation or bioptical cavity preparation
Diagnostic accuracy for proximal caries detection (dentin detection level) · Patients with permanent posterior teeth, proximal surfaces assessed clinically (in vivo) · Dentin detection level
Systematic review and meta-analysis of diagnostic studies of proximal surface caries. (2021)
Sensitivity 0.63 [0.58, 0.68]3 studiesUngraded
Fluoride concentration relative to the acceptable range (electrometric ion-selective electrode measurement; acceptable range mostly 0.6-0.8 ppmF) vs None (descriptive proportion meta-analysis)
Water samples with fluoride concentration below the acceptable range · Artificially fluoridated public water supply in Brazilian cities (water samples under external control) · Region: Southeast Brazil
External control of fluoridation in the public water supplies of Brazilian cities as a strategy against… (2021)
Prevalence 24.6NRUngraded
Special health care needs vs Not applicable
Dental caries prevalence · Arab children with special health care needs in Ras Al Khaimah · Overall
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
Prevalence 85.21 studyUngraded
Visual or visual-tactile classification systems (any system: ICDAS, ERK, Nyvad, Downer, Lussi, UniViSS, or unspecified) vs Reference standard (histology, excavation, radiographs/microCT, or tooth separation)
Specificity for detection of enamel caries · Asymptomatic children or adults presenting for clinical examination (in vivo studies), or extracted teeth of children… · Up to 3 months between index test and reference standard (in vivo studies), Permanent dentition
Visual or visual‐tactile examination to detect and inform the diagnosis of enamel caries (2021) · Cochrane
Specificity 0.76 [0.69, 0.83]NRUngraded
Intervention NR
New dental caries development · Onabotulinumtoxin A open-label, no control (Møller 2015)
Oral health effects of botulinum toxin treatment for drooling: a systematic review. (2021)
Event count (narrative; no estimate) No cases of tooth decay (0 caries events)1 studyUngraded
Clear aligners (Invisalign / thermoformed aligners) vs Fixed appliances
S. mutans counts (5th-root transformed) · Adolescents/teenagers undergoing orthodontic treatment · 1 month, Adolescents
Impact of Aligners and Fixed Appliances on Oral Health during Orthodontic Treatment: A Systematic Review and… (2021)
MD -2.22 [-6.82, 2.38]1 studyUngraded
Visual examination (VE) vs Histological validation (serial sectioning, grinding, hemisection, or microradiography)
Diagnostic accuracy for occlusal caries detection at the 1/3 dentin caries detection level (Ekstrand; D0-2 versus D3-4) · Extracted human permanent posterior teeth (premolars and molars), occlusal (pit-and-fissure) surfaces
Systematic review and meta-analysis of diagnostic methods for occlusal surface caries. (2021)
Sensitivity 0.69 [0.51, 0.82]2 studiesUngraded
Hall Technique (sealing with a preformed metal crown) vs Non-restorative cavity control (NRCC)
Failure of therapy · Children and/or adults with permanent or primary teeth, vital (sensitive) pulps, and cavitated or dentine carious… · 30 months, Cavitated lesions, primary dentition
Interventions for treating cavitated or dentine carious lesions (2021) · Cochrane
OR 0.19 [0.05, 0.74]1 study · 84 participantsVery low
Female sex vs Male sex
Mean DMFT · School children aged 11-17 years in Sharjah · Overall
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
Regression coefficient 0.41 [0.01, 0.81]1 study · 803 participantsUngraded
Xylitol-only sugar-free chewing gum vs Pooled controls: no gum, placebo/control gum, probiotic, or fluoride varnish
Streptococcus mutans load in the oral cavity (saliva and/or dental plaque) · Adults and children (general population) · Final/end-of-study time point (follow-up 2 weeks to 18 months), Overall (vs all controls)
A systematic review and meta-analysis of the role of sugar-free chewing gum on Streptococcus mutans. (2021)
SMD -0.46 [-0.64, -0.28]12 studies · 1295 participantsUngraded
Non-selective carious tissue removal and conventional restoration (CR) vs Non-restorative cavity control (NRCC)
Failure of therapy · Children and/or adults with permanent or primary teeth, vital (sensitive) pulps, and cavitated or dentine carious… · 30 months, Cavitated lesions, primary dentition
Interventions for treating cavitated or dentine carious lesions (2021) · Cochrane
OR 1.16 [0.5, 2.71]1 study · 102 participantsVery low
Intervention NR
Dental caries prevalence · General population (children and adults) in East Africa · Tanzania
Prevalence of Dental Caries and Associated Factors in East Africa, 2000-2020: Systematic Review and… (2021)
Prevalence 0.307 [0.215, 0.399]NRUngraded