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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
Atraumatic restorative treatment with high-viscosity GIC (class I) vs Amalgam restoration
Restoration success/failure · Children (5-7 years) with caries in primary teeth · 12 months
Minimal intervention dentistry for managing carious lesions into dentine in primary teeth: an umbrella review. (2022)
RR 0.93 [0.83, 1.06]3 studiesUngraded
Amalgam (A) vs Preformed metal crown (PMC)
Treatment failure (annual failure rate) · Children with carious primary molars treated by pulpotomy (vital pulp therapy) · 1 year, University, Turkey (Sonmez and Duruturk 2010), Amalgam (A) arm
Clinical effectiveness of restorative materials for the restoration of carious lesions in pulp treated… (2022)
AFR 14.31 study · 83 participantsUngraded
Intervention NR
Difference in summary sensitivity (NMA, Analysis 2) · Transillumination vs Visual
Enamel Caries Detection and Diagnosis: An Analysis of Systematic Reviews. (2022)
Sensitivity difference (95% CrI) -0.06 [-0.19, 0.05]NRUngraded
Full-mouth scaling (FMS): scaling/root planing (subgingival instrumentation) of all quadrants within 24 hours, without antiseptic vs Quadrant scaling and root planing (control): SRP of each quadrant in separate sessions at least one week apart
Pocket closure (sites with PPD <=4 mm) · Adults with a clinical diagnosis of (chronic) periodontitis (1999 classification); studies of aggressive…
Full‐mouth treatment modalities (within 24 hours) for periodontitis in adults (2022) · Cochrane
Pocket closure (sites with PPD <=4 mm after treatment): 9 studies reported; all showed increased closed pockets after treatment; 8 of 9 found no between-group difference; Koshy 2005 found a greater change in both…9 studiesUngraded
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 CDH17 (chr8q22.1) · 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), Population/community child cohorts: rural Appalachia (West Virginia, Pennsylvania) and Iowa (USA) and South West England; European / European non-Hispanic ancestry only, CDH17 (chr8q22.1); 23 (5) 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) 1.745 studies · 2974 participantsUngraded
Food and nonalcoholic beverage marketing (exposure) vs No, less, or less powerful food marketing
Food preference · Children and adolescents aged 0-19 years · Predominantly high-income countries, Nonrandomized studies
Association of Food and Nonalcoholic Beverage Marketing With Children and Adolescents' Eating Behaviors and… (2022)
SMD 0.21 [0.07, 0.35]4 studies · 1972 participantsVery low
Oral cytology (e.g. OralCDx brush biopsy, CytID) 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)
Outcome NR · 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
Oral cytology (e.g. brush biopsy) was added to the list of eligible index tests in this update; no eligible studies evaluated it (evidence gap).0 studiesNo studies
Observed population vs Not applicable
Oral problems prevalence · Pediatric leukemia patients in the United Arab Emirates · Overall
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
Prevalence 601 studyUngraded
Conventional bitewing radiography, F-speed film 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) · In vitro (laboratory; extracted teeth); permanent posterior teeth, proximal surfaces, Caries detection level
Systematic review and meta-analysis of diagnostic studies of proximal surface caries. (2021)
AUC 0.728 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), Non-histology reference standard (excavation, radiographs, separation)
Visual or visual‐tactile examination to detect and inform the diagnosis of enamel caries (2021) · Cochrane
Specificity 0.86 [0.76, 0.92]NRUngraded
TaqI (rs731236 T>C) polymorphism in the VDR gene (C allele / variant genotype) vs CT/CC genotype vs TT genotype (dominant model)
Dental caries susceptibility (risk of dental caries) · Children and adults (no age limit) assessed for dental caries susceptibility · Case-control studies of children and adults (China, India, Czech Republic, Turkey), Dentition: Mixed dentition caries
Association Between the TaqI (rs731236 T>C) Gene Polymorphism and Dental Caries Risk: A Meta-analysis. (2021)
OR 1.37 [0.81, 2.33]2 studies · 270 participantsUngraded
Analogue (conventional) radiographs 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)
Imaging modalities to inform the detection and diagnosis of early caries (2021) · Cochrane
Sensitivity 0.44 [0.38, 0.50]51 studiesUngraded
Fluoride-releasing glass ionomer-based bonding agent vs Non-fluoride glass ionomer-based bonding agent
Initiation of white spot lesions (WSL), visual-tactile assessment · Patients of any age (11-40 years) receiving comprehensive/fixed orthodontic treatment with fixed appliances · 1-24 months follow-up, Patients undergoing fixed (multibracket) orthodontic appliance treatment; clinical/dental setting; analysis at tooth level, Glass ionomer-based bonding agent
Efficacy of sealants and bonding materials during fixed orthodontic treatment to prevent enamel… (2021)
RR 0.64 [0.41, 0.99]1 study · 144 participantsUngraded
Laser fluorescence (DIAGNOdent 2190/pen) vs Histological validation of dental tissues (gold standard)
Diagnostic accuracy for proximal caries detection (dentin detection level) · Extracted permanent posterior teeth with proximal surfaces (in vitro) · In vitro (laboratory; extracted teeth); permanent posterior teeth, proximal surfaces, Dentin detection level
Systematic review and meta-analysis of diagnostic studies of proximal surface caries. (2021)
AUC 0.835 studiesUngraded
Bonded Minne appliance (slow maxillary expansion) vs Banded Minne appliance (slow maxillary expansion)
Stability of crossbite correction (relapse of canine expansion) · Children and adults with a posterior crossbite, without a Class III skeletal relationship, cleft lip or palate (or… · 24 weeks after completion of expansion
Orthodontic treatment for posterior crossbites (2021) · Cochrane
Bonded Minne 1.6 mm (SD 0.5) vs Banded Minne 1.2 mm (SD 0.3); P=NS1 studyUngraded
Double primary (canine and first molar) tooth extraction vs Single primary (canine) tooth extraction
Root resorption of the impacted canine or adjacent incisors and first premolars · Young people aged 9 to 14 years diagnosed with one or both palatally displaced permanent maxillary canines (PDC)
Interventions for promoting the eruption of palatally displaced permanent canine teeth, without the need for… (2021) · Cochrane
The studies did not report adverse events.0 studiesNo studies
TaqI (rs731236 T>C) polymorphism in the VDR gene (C allele / variant genotype) vs CC genotype vs TT genotype (homozygous model)
Dental caries susceptibility (risk of dental caries) · Children and adults (no age limit) assessed for dental caries susceptibility · Case-control studies of children and adults (China, India, Czech Republic, Turkey), Ethnicity: Asian
Association Between the TaqI (rs731236 T>C) Gene Polymorphism and Dental Caries Risk: A Meta-analysis. (2021)
OR 1.38 [0.55, 3.50]5 studies · 1932 participantsUngraded
Presence of dental plaque vs Absence of dental plaque
Dental caries (presence) · Individuals in Ethiopia assessed for dental caries · Community-, school-, and hospital/clinic-based populations across regions of Ethiopia
Dental caries and associated factors in Ethiopia: systematic review and meta-analysis. (2021)
OR 5.14 [0.67, 39.39]3 studiesUngraded
Conventional bitewing radiography, E-speed film 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) · In vitro (laboratory; extracted teeth); permanent posterior teeth, proximal surfaces, Caries detection level
Systematic review and meta-analysis of diagnostic studies of proximal surface caries. (2021)
Sensitivity 0.42 [0.28, 0.57]9 studiesUngraded
Intervention NR
Water samples with fluoride concentration below the acceptable range
External control of fluoridation in the public water supplies of Brazilian cities as a strategy against… (2021)
Prevalence 45.0 [26.1, 64.7]12 studiesUngraded
Fixed Hyrax maxillary expander vs Fixed fan-type maxillary expander
Canine expansion · Children and adults with a posterior crossbite, without a Class III skeletal relationship, cleft lip or palate (or… · post-treatment 3 weeks
Orthodontic treatment for posterior crossbites (2021) · Cochrane
Gopalakrishnan 2017: Hyrax 6.00 (SD 0.63) mm vs fan-type 7.33 (SD 2.5) mm; P=0.235 (NS)1 study · 12 participantsUngraded
Observed population vs Not applicable
Dental caries prevalence · Preschool children attending Al Ain pediatric dentistry department · Overall
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
Prevalence 99.41 study · 176 participantsUngraded
Chemotherapy regimen A (+/- locoregional treatment) vs Chemotherapy regimen B (+/- locoregional treatment)
Disease-free survival, chemotherapy regimen A vs regimen B · People receiving curative-intent treatment for oral cavity and oropharyngeal (squamous cell) cancer
Interventions for the treatment of oral cavity and oropharyngeal cancer: chemotherapy (2021) · Cochrane
Induction cisplatin+5-FU+docetaxel vs cisplatin+5-FU: disease-free survival HR 0.72 (95% CI 0.57 to 0.91, P = 0.006; Vermorken 2007). Prior to concurrent chemoradiation: Posner 2007 HR 0.71 (0.56 to 0.90, P = 0.005).…2 studiesUngraded
Intensive periodontal treatment (subgingival SRP with or without other periodontal treatment) vs Supra-gingival scaling
Change in diastolic blood pressure (DBP, mmHg) · Adults (any age/sex) with chronic periodontitis (>=5 teeth remaining; PPD >4 mm), with or without hypertension · Short term (follow-up 2 months), People diagnosed with periodontitis and hypertension
Effect of periodontal treatments on blood pressure (2021) · Cochrane
MD -8.40 [-12.19, -4.61]1 study · 101 participantsModerate
External control of fluoride concentration vs Not applicable
Samples with fluoride concentration outside the acceptable range · Brazilian cities with artificially fluoridated public water supplies · 1995-2013, Brazil, Sensitivity analysis excluding Silva et al.
External control of fluoridation in the public water supplies of Brazilian cities as a strategy against… (2021)
Prevalence 47.1 [39.6, 54.7]11 studiesUngraded
Lacebacks with fixed appliances vs Fixed appliances only (control)
Size of the lower jaw (arch length) · Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth · 6 months
Orthodontic treatment for crowded teeth in children (2021) · Cochrane
MD 0.83 [-6.41, 8.07]1 study · 62 participantsUngraded
Intervention NR
Mean DMFT (decayed, missing, filled permanent teeth) · Individuals with permanent dentition in East Africa · Community- and school-based populations, East Africa, Ethiopia
Prevalence of Dental Caries and Associated Factors in East Africa, 2000-2020: Systematic Review and… (2021)
MEAN 1.182 [1.135, 1.229]NRUngraded
Induction chemotherapy plus locoregional treatment (radiotherapy and/or surgery) vs Locoregional treatment (radiotherapy and/or surgery) alone
Overall survival, induction cisplatin + 5-fluorouracil + docetaxel prior to concurrent chemoradiation (cisplatin) vs concurrent chemoradiation (cisplatin) · People receiving curative-intent treatment for oral cavity and oropharyngeal (squamous cell) cancer
Interventions for the treatment of oral cavity and oropharyngeal cancer: chemotherapy (2021) · Cochrane
HR 1.08 [0.80, 1.44]3 studies · 760 participantsLow
Laser fluorescence (DIAGNOdent 2095) 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 · in vitro
Systematic review and meta-analysis of diagnostic methods for occlusal surface caries. (2021)
AUC 0.816 studiesUngraded
Intervention NR
Mean dmft (decayed, missing, filled primary teeth) · Children with primary dentition in East Africa · Community- and school-based populations, East Africa
Prevalence of Dental Caries and Associated Factors in East Africa, 2000-2020: Systematic Review and… (2021)
MEAN 2.237 [1.293, 3.181]11 studiesUngraded
Maternal smoking during pregnancy vs No maternal smoking during pregnancy
Dental caries · Children · Community/population-based (multiple countries), Children's age: over 3 years
Asked by 2 reviewsCorrelation Between Maternal Smoking During Pregnancy and Dental Caries in Children: A Systematic Review and… (2021)
OR 1.56 [1.46, 1.67]3 studiesUngraded
High snack consumption vs Low snack consumption
Severe early childhood caries · Children aged 5-6 years in Ajman schools · Overall
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
OR 1.80 [1.26, 2.58]1 study · 1036 participantsUngraded
Intervention NR
Dental caries prevalence · Somalia
Prevalence of Dental Caries and Associated Factors in East Africa, 2000-2020: Systematic Review and… (2021)
Prevalence 0.414 [0.109, 0.719]2 studiesUngraded
ARP with demineralised bone matrix, single particle size vs ARP with demineralised bone matrix, multiple particle size
Complications (e.g. discomfort, pain and swelling) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months
Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane
Included study (Hoang 2012) reported there were no adverse effects1 study · 30 participantsVery low
Induction chemotherapy plus locoregional treatment (radiotherapy and/or surgery) vs Locoregional treatment (radiotherapy and/or surgery) alone
Locoregional control, induction cisplatin + 5-fluorouracil + docetaxel prior to concurrent chemoradiation vs concurrent chemoradiation · People receiving curative-intent treatment for oral cavity and oropharyngeal (squamous cell) cancer
Interventions for the treatment of oral cavity and oropharyngeal cancer: chemotherapy (2021) · Cochrane
RR 0.80 [0.64, 0.99]3 studiesUngraded
Schwarz appliance vs No active treatment (control)
Size of the lower jaw (mandibular arch length, change) at 9 months · Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth · 9 months
Orthodontic treatment for crowded teeth in children (2021) · Cochrane
MD 0.11 [-0.46, 0.68]1 study · 28 participantsUngraded
Systemic sclerosis (SSc / scleroderma) vs SSc-free individuals (controls)
Probing depth (PD) · Adults (general and hospital populations assessed in case-control studies) · Hospital/clinic-based case-control studies from Asia, America and Europe
Oral manifestations of patients with systemic sclerosis: a meta-analysis for case-controlled studies. (2021)
SMD 3.101 [1.374, 4.829]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), Reference standard: enhanced visual (non-CBCT)
Imaging modalities to inform the detection and diagnosis of early caries (2021) · Cochrane
Sensitivity 0.47 [0.29, 0.66]8 studiesUngraded
Conventional bitewing radiography, E-speed film vs Histological validation of dental tissues (gold standard)
Diagnostic accuracy for proximal caries detection (dentin detection level) · Extracted permanent posterior teeth with proximal surfaces (in vitro) · In vitro (laboratory; extracted teeth); permanent posterior teeth, proximal surfaces, Dentin detection level
Systematic review and meta-analysis of diagnostic studies of proximal surface caries. (2021)
DOR 31.40 [14.31, 68.93]5 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)
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), Primary/mixed dentition
Visual or visual‐tactile examination to detect and inform the diagnosis of enamel caries (2021) · Cochrane
Sensitivity 0.87 [0.80, 0.92]NRUngraded
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), Permanent dentition (non-CBCT)
Imaging modalities to inform the detection and diagnosis of early caries (2021) · Cochrane
Sensitivity 0.44 [0.37, 0.51]NRUngraded
ARP with alloplast plus barrier membrane vs ARP with alloplast without membrane
Changes in vertical height of alveolar ridge (mm) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 9 months
Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane
MD 0.38 [0.26, 0.5]1 study · 20 participantsVery low
Non-selective carious tissue removal and conventional restoration (CR) vs Selective carious tissue removal (selective excavation, SE)
Failure of therapy · Children and/or adults with permanent or primary teeth, vital (sensitive) pulps, and cavitated or dentine carious… · 12 months, Cavitated but not deep lesions, primary dentition
Interventions for treating cavitated or dentine carious lesions (2021) · Cochrane
OR 0.62 [0.21, 1.88]2 studies · 204 participantsVery low
Digital bitewing radiography, phosphor plate (PSP) 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) · In vivo (clinical); permanent posterior teeth, proximal surfaces, Dentin detection level
Systematic review and meta-analysis of diagnostic studies of proximal surface caries. (2021)
Specificity 0.60 [0.20, 0.90]1 studyUngraded
Visual classification: ICDAS (International Caries Detection and Assessment System) 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)
Visual or visual‐tactile examination to detect and inform the diagnosis of enamel caries (2021) · Cochrane
Specificity 0.76 [0.67, 0.83]36 studiesUngraded
Private day care vs Public day care
Dental caries prevalence · Preschool children in Sharjah day cares · Private day cares
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
Prevalence 771 study · 435 participantsUngraded
ARP with alloplast plus barrier membrane vs ARP with alloplast without membrane
Aesthetic outcomes of future prosthodontic rehabilitation · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 9 months
Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane
Outcome not reported0 studiesNo studies
Conventional bitewing radiography, F-speed film 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) · In vitro (laboratory; extracted teeth); permanent posterior teeth, proximal surfaces, Caries detection level
Systematic review and meta-analysis of diagnostic studies of proximal surface caries. (2021)
Specificity 0.88 [0.74, 0.95]8 studiesUngraded
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) · In vivo (clinical); permanent posterior teeth, proximal surfaces, Dentin detection level
Systematic review and meta-analysis of diagnostic studies of proximal surface caries. (2021)
Specificity 0.60 [0.15, 0.93]3 studiesUngraded
Double primary (canine and first molar) tooth extraction vs Single primary (canine) tooth extraction
Incidence of eruption of the PDC into the mouth · Young people aged 9 to 14 years diagnosed with one or both palatally displaced permanent maxillary canines (PDC) · 48 months (maximum; mITT)
Interventions for promoting the eruption of palatally displaced permanent canine teeth, without the need for… (2021) · Cochrane
RR 1.28 [1.06, 1.54]2 studies · 96 participantsUngraded