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

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10,375 questions in 429 reviews · Oral Health

current versions
No 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.

QuestionEffectEvidenceStatus / GRADE
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
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
MEAN 5.93 [4.82, 7.28]14 studies · 17658 participantsUngraded
Fluoride-containing dental care products, primarily toothpaste vs Dietary fluoride sources in high-fluoridated areas
Contribution to total daily fluoride intake · Children · High fluoride in water (0.78-1.5 mg/L)
Fluoride Intake Through Dental Care Products: A Systematic Review. (2022)
Mean percentage contribution 418 studiesUngraded
Living with HIV and undergoing antiretroviral therapy (ART/HAART) vs Healthy HIV-negative controls
Mucocele · 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)
OR 3.03 [0.12, 75.37]1 study · 190 participantsUngraded
Autopolymerised sealant vs Light polymerised sealant
Adverse events · Children with sound primary molars, aged 2-4 years (municipal dental clinics or hospital paediatric clinics, Denmark)
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
No studies reported this outcome.0 studiesNo studies
Ion-releasing glass ionomer cement (GIC) restorations vs Resin composite restorations
Secondary caries · Patients with permanent dentition in need of restorations · 1 year, All types of cavities
Secondary caries and marginal adaptation of ion-releasing versus resin composite restorations: a systematic… (2022)
RD -0.00 [-0.01, 0.01]12 studies · 1677 participantsLow
Flowable resin composite vs Fluoride-releasing resin-based sealant
Adverse events · Children who were regular dental attenders with caries-free first or second primary molars (public health service…
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
No studies reported this outcome.0 studiesNo studies
Prior SDF application with a rinsing step vs No prior SDF application (untreated dentin control)
Immediate bond strength (MPa) · Glass-ionomer cement bonded to caries-affected dentin (in vitro) · Immediate bond strength, Caries-affected dentin (with rinsing step)
Bonding of Glass-Ionomer Cement and Adhesives to Silver Diamine Fluoride-treated Dentin: An Updated… (2022)
MD -0.36 [-1.07, 0.35]5 studies · 178 participantsUngraded
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) · Glass-ionomer cement 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 -0.11 [-0.54, 0.31]11 studies · 583 participantsUngraded
Restorative materials placed by atraumatic restorative treatment (ART); mostly high-viscosity/conventional GIC, also RMGIC, glass carbomer, compomer, composite resin vs Different ART materials or application techniques (e.g., bilayer vs single-step, with vs without cavity conditioner/disinfectant), or composite resin
Treatment failure (annual failure rate) · Children with carious primary teeth treated by atraumatic restorative treatment (hand-instrument caries removal), no… · 12-48 months, Restorative technique (ART)
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) 1.2-37.1%10 studiesUngraded
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 · Data collection period: >2015
Prevalence of dental caries in the permanent dentition amongst 12-year-olds in Africa: a systematic review… (2022)
MEAN 1.802 [1.492, 2.111]6 studiesUngraded
Behaviour change / oral health promotion interventions delivered by non-dental professionals and health workers (nurses, midwives, health visitors, community health workers) vs Control (usual care, no intervention, or comparison group)
Caries experience at the surface level (dmfs/defs) · Children (mean age newborn to ~5.2 years) and their parents/carers
The effectiveness of behaviour change interventions delivered by non-dental health workers in promoting… (2022)
SMD -0.15 [-0.25, -0.04]12 studiesUngraded
Delicate surgery and wound closure by primary intention vs Non-traumatic tooth avulsion and wound closure by secondary intention
Rate of complications and side effects of the intervention · People treated with oral bisphosphonates undergoing dental extractions (at risk of MRONJ)
Interventions for managing medication‐related osteonecrosis of the jaw (2022) · Cochrane
No intraoperative complications were observed in either of the two groups.1 study · 700 participantsUngraded
Dental caries (carious oral microbiome) vs Caries-free / healthy oral microbiome
Alpha diversity (Shannon) · Children providing oral (saliva/supragingival plaque) 16S rRNA microbiome samples · Children
Meta-analysis of caries microbiome studies can improve upon disease prediction outcomes. (2022)
In children, the Shannon alpha-diversity index differed significantly between caries and health (p < 0.001).NRUngraded
Visual or visual-tactile classification (e.g., ICDAS, ERK) vs Reference standard (histology, operative excavation, or enhanced visual examination)
Sensitivity 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)
Sensitivity 0.83 [0.77, 0.87]64 studies · 24567 participantsLow
Dentinal caries in primary dentition (at 5 years) vs Caries-free primary dentition
Dentinal caries in permanent (newly erupted) teeth · School children and adolescents (6-18 years) followed from primary dentition (baseline examination before 72 months of… · 7-year follow-up, Dentinal caries in primary dentition
Does Early Childhood Caries Increase Caries Development among School Children and Adolescents? A Systematic… (2022)
OR 3.2 [2.6, 3.9]1 study · 3282 participantsUngraded
Dental caries (carious oral microbiome) vs Caries-free / healthy oral microbiome
Discrimination of caries vs health (random forest ROC-AUC) · 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)
AUC 0.7519 studies · 2016 participantsUngraded
Chlorhexidine (CHX) vs Boric acid
Reduction in level of contamination by particles >5 um (droplets) at <2 m from patient's oral cavity · Dental patients undergoing aerosol-generating procedures (AGPs) and the dental healthcare providers treating them · assistant level
Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental… (2022) · Cochrane
MD -8.03 [-9.65, -6.41]1 study · 60 participantsVery low
Glass ionomer-based sealant vs No sealant
Retention of sealant (complete or partial retention) · Children with caries-free primary first molars (with or without caries on other teeth), aged 1-5 years (paediatric… · 6-30 months
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
Chadwick 2005: one or more sealants fully/partially retained in 69 (31.2%) children at 12-30 months; Joshi 2019: at 12 months 75 (43.6%) teeth completely retained, 58 (33.7%) partially retained, 39 (22.7%) completely…2 studiesUngraded
Hall Technique preformed metal crowns vs Conventional restorations (amalgam, GIC, composite)
Discomfort during treatment · Children (3-10 years) with dentine caries in primary molars · During treatment
Minimal intervention dentistry for managing carious lesions into dentine in primary teeth: an umbrella review. (2022)
RR 1.67 [0.65, 4.25]2 studiesUngraded
HVGIC vs Composite resin
Restoration failure · Children with carious primary teeth · 3 years, Class II
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) HVGIC 6.1%; composite resin 1.7%1 study · 87 participantsUngraded
Preformed metal crown (PMC) vs Resin-modified glass-ionomer cement + composite resin (modified open-sandwich restoration)
Treatment failure (annual failure rate) · Children with carious primary molars treated by pulpotomy (vital pulp therapy) · 2 years, PMC arm
Clinical effectiveness of restorative materials for the restoration of carious lesions in pulp treated… (2022)
AFR 2.51 study · 87 participantsUngraded
Antiretroviral therapy (any, including cART) vs No antiretroviral medication (treatment-naive)
Mucocele 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 0.02 [0.00, 1.09]NRVery low
HVGIC Fuji IX vs HVGIC Amalgomer CR
Restoration failure · Children with carious primary teeth · 1 year, ART; Class I and II
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) Fuji IX 9.0%; Amalgomer CR 4.0% (cumulative)1 study · 100 participantsUngraded
Antibiotic prophylaxis before dental procedure vs No antibiotic prophylaxis or placebo
Mortality or serious adverse events requiring hospitalisation · Adults or children at increased risk of bacterial endocarditis (pre-existing cardiac condition) undergoing an invasive…
Antibiotic prophylaxis for preventing bacterial endocarditis following dental procedures (2022) · Cochrane
Mortality or serious adverse events requiring hospitalisation | No data reported | 248 (1 study) | - | -0 studiesNo studies
Machine-learning algorithms for dental caries detection vs Different machine-learning algorithms for caries prediction
Dental caries detection accuracy · Dental images of human beings · Zanella-Calzada et al., 2018; ANN
Uses of Different Machine Learning Algorithms for Diagnosis of Dental Caries. (2022)
Accuracy 691 study · 189 participantsUngraded
Single-visit root canal treatment vs Multiple-visit root canal treatment (two or more visits)
Pain at two weeks (postobturation) · People aged 10 years or above requiring root canal treatment; permanent teeth with completely formed apex and without… · Two weeks postobturation
Single versus multiple visits for endodontic treatment of permanent teeth (2022) · Cochrane
RR 0.56 [0.07, 4.69]2 studies · 288 participantsUngraded
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
Prevalence of dental caries in the permanent dentition amongst 12-year-olds in Africa: a systematic review… (2022)
Prevalence 0.36 [0.294, 0.417]25 studies · 18080 participantsUngraded
Dental caries (early childhood caries, ECC) vs Caries-free controls
Relative abundance of Veillonella spp. · Children with early childhood caries (ECC) and caries-free children · Overall (all sample types)
Meta-Analysis Using NGS Data: The Veillonella Species in Dental Caries. (2022)
MD 2.22 [0.54, 3.90]6 studies · 319 participantsVery low
HVGIC with chlorhexidine cavity disinfectant vs HVGIC without cavity disinfectant
Restoration failure · Children with carious primary teeth · 2 years, ART; Class I and II
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) without disinfectant 9.1%; with disinfectant 11.1% (cumulative)1 study · 126 participantsUngraded
Tempered cetylpyridinium chloride vs Cold cetylpyridinium chloride
Reduction in level of contamination by particles >5 um (droplets) at <2 m from patient's oral cavity · Dental patients undergoing aerosol-generating procedures (AGPs) and the dental healthcare providers treating them · assistant level
Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental… (2022) · Cochrane
MD -8.6 [-14.7, -2.5]1 study · 20 participantsVery low
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… · 3 years
Secondary caries and marginal adaptation of ion-releasing versus resin composite restorations: a systematic… (2022)
RD 0.00 [-0.02, 0.02]3 studies · 321 participantsLow
Autofluorescence-guided bone surgery vs Conventional bone surgery
Healing of MRONJ · People with established (manifest) MRONJ · 1 year
Interventions for managing medication‐related osteonecrosis of the jaw (2022) · Cochrane
RR 1.08 [0.85, 1.37]1 study · 30 participantsVery low
Common genetic variants genome-wide (GWAS; ~3.9 million SNPs with MAF > 5%) vs ECC-unaffected children (per-allele case-control association)
Early childhood caries (ECC) - association at lead SNP rs1044956 (7:24854765; nearest gene(s) OSBPL3, NPVF) · 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), rs1044956 (7:24854765); effect/non-effect allele A/G; MAF 0.49; direction across 5 cohorts +++++
Association of Early Childhood Caries with Bitter Taste Receptors: A Meta-Analysis of Genome-Wide… (2022)
Z-score (Stouffer's combined Z, 5 cohorts) 4.5515 studies · 2974 participantsUngraded
Chlorhexidine (CHX) vs Povidone iodine
Reduction in level of contamination by particles <=5 um (droplet nuclei) at >=2 m from patient's oral cavity · Dental patients undergoing aerosol-generating procedures (AGPs) and the dental healthcare providers treating them · droplet nuclei; aerobic cultures (9 feet behind patient)
Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental… (2022) · Cochrane
MD 0.2 [-7.28, 7.68]1 study · 40 participantsVery low
Caries assessment at dentine threshold (cavitation into dentine) vs None (descriptive prevalence review; subgroup analyses only)
Caries prevalence · European adolescents aged 12–19 years · Publication year: ≥ 2010
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
Prevalence 0.51 [0.36, 0.66]11 studiesUngraded
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 · Setting: Rural
Prevalence of dental caries in the permanent dentition amongst 12-year-olds in Africa: a systematic review… (2022)
Prevalence 0.314 [0.186, 0.443]10 studiesUngraded
Food and nonalcoholic beverage marketing (exposure) vs No, less, or less powerful food marketing
Food intake · Children and adolescents aged 0-19 years · Immediate/short-term (post-exposure), Nonrandomized studies
Association of Food and Nonalcoholic Beverage Marketing With Children and Adolescents' Eating Behaviors and… (2022)
SMD 0.34 [0.12, 0.57]11 studies · 8436 participantsVery low
Combined antiretroviral therapy (cART) vs No antiretroviral medication (treatment-naive)
Oral candidiasis prevalence · Children and adolescents (<18 years) living with HIV (CLWH) · cART
Impact of Antiretroviral Therapy on Oral Health among Children Living with HIV: A Systematic Review and… (2022)
OR 0.35 [0.24, 0.51]NRVery low
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 8-15 years
Effectiveness of primary school-based interventions in improving oral health of children in low- and… (2022)
SMD -0.41 [-0.50, -0.32]NRUngraded
Autopolymerised sealant vs Light polymerised sealant
Retention of sealant (complete or partial retention) · Children with sound primary molars, aged 2-4 years (municipal dental clinics or hospital paediatric clinics, Denmark) · 24-36 months
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
OR 0.68 [0.33, 1.44]1 study · 52 participantsVery low
Intervention NR
Caries experience - % with caries (descriptive), primary dentition · CL/P vs no CL/P; Table 4 (7 groups/6 studies)
Caries in children with and without orofacial clefting: A systematic review and meta-analysis. (2022)
% caries experience CL/P 64.84% vs no CL/P 52.13%6 studiesUngraded
Fluoride-releasing resin-based sealant vs No sealant (no treatment)
Retention of sealant (complete or partial retention) · Children with caries-free or non-cavitated carious lesion primary molars, aged 3-7 years (paediatric department,… · 12-24 months
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
At 12 months, sealants on 96 (70.1%) surfaces completely retained, 25 (18.3%) partially retained, 16 (11.6%) completely lost; at 24 months, 58 (45.3%) completely retained, 29 (22.7%) partially retained, 41 (32%)…1 studyUngraded
Monotherapy or dual antiretroviral therapy vs No antiretroviral medication (treatment-naive)
Oral candidiasis prevalence · Children and adolescents (<18 years) living with HIV (CLWH) · monotherapy or dual therapy
Impact of Antiretroviral Therapy on Oral Health among Children Living with HIV: A Systematic Review and… (2022)
No significant difference in oral candidiasis prevalence was found between treatment-naive CLWH and those under monotherapy or dual therapy (no numeric estimate reported in the text).NRVery low
Referral letter based on the common-sense model (CSM) of self-regulation vs Standard referral letter
Proportion of children with treated/untreated caries (receipt of dental care) · School children, primary schools in the USA · mean 8 months
School dental screening programmes for oral health (2022) · Cochrane
OR 0.97 [0.62, 1.51]1 study · 388 participantsVery low
Fluoride-releasing resin-based sealant vs No sealant (no treatment)
Adverse events · Children with caries-free or non-cavitated carious lesion primary molars, aged 3-7 years (paediatric department,…
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
No studies reported this outcome.0 studiesNo studies
Amalgam vs Conventional GIC
Restoration failure · Children with carious primary teeth · 5 years, Class I and II
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) amalgam 4.4%; conventional GIC 7.6%1 study · 76 participantsUngraded
Common genetic variants genome-wide (GWAS; ~3.9 million SNPs with MAF > 5%) vs ECC-unaffected children (per-allele case-control association)
Early childhood caries (ECC) - association at lead SNP rs9889096 (16:13575143; nearest gene(s) SHISA9) · 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), rs9889096 (16:13575143); effect/non-effect allele T/G; MAF 0.50; direction across 5 cohorts --+--
Association of Early Childhood Caries with Bitter Taste Receptors: A Meta-Analysis of Genome-Wide… (2022)
Z-score (Stouffer's combined Z, 5 cohorts) -4.5415 studies · 2974 participantsUngraded
Flowable resin composite vs Fluoride-releasing resin-based sealant
Progression of non-cavitated enamel caries · Children who were regular dental attenders with caries-free first or second primary molars (public health service…
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
No studies reported this outcome.0 studiesNo studies
Povidone iodine 1% vs Control
Presence of dry socket · Adults (>18 years) having permanent tooth extraction (predominantly mandibular third molars) · Follow-up: median 7 days
Local interventions for the management of alveolar osteitis (dry socket) (2022) · Cochrane
RR 0.36 [0.14, 0.98]1 study · 189 participantsUngraded
Criteria-based screening with specific (personalised) referral letter vs Criteria-based screening with non-specific referral letter
Dental attendance at orthodontist · School children, secondary school in the UK (aged 11 to 13 years) · mean 8 months
School dental screening programmes for oral health (2022) · Cochrane
RR 1.90 [1.18, 3.06]1 study · 201 participantsVery low