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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)

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
Extraction of the primary (baby) canine (single primary tooth extraction) vs No extraction (non-intervention control)
Patient-reported outcomes (pain, discomfort and analgesic use) · Young people aged 9 to 14 years diagnosed with one or both palatally displaced permanent maxillary canines (PDC) · Evening after extraction and one week later
Interventions for promoting the eruption of palatally displaced permanent canine teeth, without the need for… (2021) · Cochrane
Self-reported VAS pain (Naoumova 2012): pain and discomfort from extraction of the primary canine were low both during and after the procedure and mostly absent at one week; 35% of boys and 50% of girls took one dose…1 study · 44 participantsUngraded
Nd:YAG laser (neodymium-doped:yttrium-aluminum-garnet) vs Placebo (placebo laser or placebo agent) or no treatment
Changes in intensity of pain (VAS 0 to 10) tested through tactile stimuli · Patients aged above 12 years with self-reported tooth hypersensitivity confirmed on clinical evaluation · Medium term (24 hours to 2 months)
Laser therapy for dentinal hypersensitivity (2021) · Cochrane
MD -1.06 [-2.15, 0.03]2 studiesUngraded
Inflammatory bowel disease (IBD; Crohn's disease or ulcerative colitis) vs Healthy controls without IBD
Periodontal disease (periodontitis) coincidence · Patients with inflammatory bowel disease (IBD) and controls without IBD; mostly adults (one pediatric study), both sexes · Hospital/clinic-based case-control and cross-sectional studies in 11 countries; 15 studies total (1748 participants: 1104 Crohn's disease, 534 ulcerative colitis, 110 IBD-form unspecified); 6 studies pooled for this analysis
Oral Health Status in Patients with Inflammatory Bowel Diseases: A Systematic Review. (2021)
OR 2.49 [1.97, 3.15]6 studiesUngraded
Digital bitewing radiography, sensor-based (CCD/CMOS) vs Direct visual examination after tooth separation or bioptical cavity preparation
Diagnostic accuracy for proximal caries detection (caries detection level) · Patients with permanent posterior teeth, proximal surfaces assessed clinically (in vivo) · In vivo (clinical); permanent posterior teeth, proximal surfaces, Caries detection level
Systematic review and meta-analysis of diagnostic studies of proximal surface caries. (2021)
Sensitivity 0.55 [0.42, 0.67]1 studyUngraded
Fixed expander with differential opening expansion (DOE) vs Fixed fan-type expander
Crossbite correction · Children and adults with a posterior crossbite, without a Class III skeletal relationship, cleft lip or palate (or…
Orthodontic treatment for posterior crossbites (2021) · Cochrane
Massaro 2020: differential opening 24/24 vs fan-type 18/24 crossbites corrected1 studyUngraded
Intervention NR
Dental caries prevalence · General population in Ethiopia (all ages, age range 6-100 years) · Community-, school-, and hospital/clinic-based populations across regions of Ethiopia, Tigray
Dental caries and associated factors in Ethiopia: systematic review and meta-analysis. (2021)
Prevalence 0.4659 [0.2464, 0.6854]2 studiesUngraded
Laser fluorescence pen (DIAGNOdent 2190/Pen) 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 · in vitro
Systematic review and meta-analysis of diagnostic methods for occlusal surface caries. (2021)
DOR 5.85 [1.77, 19.30]4 studiesUngraded
ARP with allograft vs ARP with xenograft
Implant failure rate · 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
Outcome not reported0 studiesNo studies
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)
DOR 6.80 [4.58, 10.10]9 studiesUngraded
Digital bitewing radiography (phosphor plates) 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 · in vitro
Systematic review and meta-analysis of diagnostic methods for occlusal surface caries. (2021)
Sensitivity 0.48 [0.24, 0.73]2 studiesUngraded
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), Primary dentition (non-CBCT)
Imaging modalities to inform the detection and diagnosis of early caries (2021) · Cochrane
Specificity 0.87 [0.77, 0.93]NRUngraded
Cone beam computed tomography (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 (CBCT)
Imaging modalities to inform the detection and diagnosis of early caries (2021) · Cochrane
Sensitivity 0.68 [0.42, 0.86]NRUngraded
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)
AUC 0.925 studiesUngraded
Observed population vs Not applicable
Tooth brushing less than once daily, males in 2016 · Nationally surveyed adolescents 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 46.11 study · 24220 participantsUngraded
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 · in vitro
Systematic review and meta-analysis of diagnostic methods for occlusal surface caries. (2021)
Sensitivity 0.97 [-0.92, 0.99]1 studyUngraded
ARP with alloplast plus barrier membrane vs ARP with alloplast without membrane
Need for additional augmentation prior to implant placement · 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
Laser fluorescence (DIAGNOdent 2190/pen) 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)
DOR 30.79 [8.74, 108.51]5 studiesUngraded
Laser fluorescence (DIAGNOdent 2190/pen) 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 0.79 [0.62, 0.90]5 studiesUngraded
Semi-rapid maxillary expansion vs Rapid maxillary expansion
Molar expansion · Children and adults with a posterior crossbite, without a Class III skeletal relationship, cleft lip or palate (or…
Orthodontic treatment for posterior crossbites (2021) · Cochrane
MD 0.60 [-0.55, 1.75]1 study · 35 participantsUngraded
Vital staining (e.g. toluidine blue, tolonium chloride) vs Surgical or punch biopsy with histological assessment
Sensitivity · Adults (aged 16 years or over) presenting to primary or secondary care with clinically evident suspicious or innocuous…
Diagnostic tests for oral cancer and potentially malignant disorders in patients presenting with clinically… (2021) · Cochrane
Sensitivity 0.86 [0.79, 0.90]20 studiesLow
Visual examination (VE) 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 0.85 [0.74, 0.92]9 studiesUngraded
Maternal smoking during pregnancy vs No maternal smoking during pregnancy
Dental caries · Children · Community/population-based (multiple countries), Children's age: 3 years or younger
Asked by 2 reviewsCorrelation Between Maternal Smoking During Pregnancy and Dental Caries in Children: A Systematic Review and… (2021)
OR 1.71 [1.34, 2.16]3 studiesUngraded
Autism spectrum disorder vs Not applicable
Poor oral hygiene prevalence · Autistic children and young adults in Dubai · Overall
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
Prevalence 591 studyUngraded
Systemic antibiotic prophylaxis (any regimen; topical therapy excluded) administered before and/or after tooth extraction vs Placebo
Swelling (7th day) · People undergoing tooth extraction (21 of 23 trials: healthy patients undergoing impacted third molar extraction; 1… · 7th day
Antibiotics to prevent complications following tooth extractions (2021) · Cochrane
RR 0.80 [0.50, 1.27]4 studies · 452 participantsVery low
Conventional bitewing radiography (F-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 · in vitro
Systematic review and meta-analysis of diagnostic methods for occlusal surface caries. (2021)
DOR 23.60 [8.28, 67.24]2 studiesUngraded
Nd:YAG laser (neodymium-doped:yttrium-aluminum-garnet) vs Placebo (placebo laser or placebo agent) or no treatment
Changes in intensity of pain (VAS 0 to 10) tested through air blast stimuli · Patients aged above 12 years with self-reported tooth hypersensitivity confirmed on clinical evaluation · Short term (0 to 24 hours)
Laser therapy for dentinal hypersensitivity (2021) · Cochrane
MD 0.22 [-0.55, 0.99]2 studiesUngraded
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) · Pakistan (school-, community-, and hospital/clinic-based cross-sectional surveys), Dentition: primary
Prevalence of dental caries in Pakistan: a systematic review and meta-analysis. (2021)
Prevalence 50.493 [43.867, 57.110]NRUngraded
Double primary (canine and first molar) tooth extraction vs Single primary (canine) tooth extraction
Reported improvement in the position of the ectopic canine measured from radiographs · 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
no estimate extracted0 studiesNo studies
Autism spectrum disorder vs Healthy counterparts
Dental-care visit prevalence · Children with autism spectrum disorder in Dubai · Overall
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
Prevalence 651 studyUngraded
Non-selective carious tissue removal and conventional restoration (CR) vs Hall Technique (sealing with a preformed metal crown)
Efficiency, costs or cost-effectiveness · Children and/or adults with permanent or primary teeth, vital (sensitive) pulps, and cavitated or dentine carious… · Primary dentition
Interventions for treating cavitated or dentine carious lesions (2021) · Cochrane
Cost-effectiveness reported narratively: HT found more cost-effective than CR in primary teeth (Innes 2011; Santamaria 2018); not GRADE-rated.2 studiesUngraded
Double primary (canine and first molar) tooth extraction vs Single primary (canine) tooth extraction
Patient-reported outcome measures (PROMs), including quality of life and pain · 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
no estimate extracted0 studiesNo studies
Systemic antibiotic prophylaxis (any regimen; topical therapy excluded) administered before and/or after tooth extraction vs Placebo
Pain (continuous, VAS 0-10 cm, 7th day) · People undergoing tooth extraction (21 of 23 trials: healthy patients undergoing impacted third molar extraction; 1… · 6th to 7th day
Antibiotics to prevent complications following tooth extractions (2021) · Cochrane
MD -0.26 [-0.59, 0.07]4 studies · 422 participantsVery low
Cone beam computed tomography (CBCT) vs Digital radiographs (direct within-person / paired comparison); reference standard: histology
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), Digital
Imaging modalities to inform the detection and diagnosis of early caries (2021) · Cochrane
Specificity 0.76 [0.43, 0.93]6 studiesUngraded
Intervention NR
Dental caries prevalence · General population in Ethiopia (all ages, age range 6-100 years) · Community-, school-, and hospital/clinic-based populations across regions of Ethiopia
Dental caries and associated factors in Ethiopia: systematic review and meta-analysis. (2021)
Prevalence 0.4098 [0.3162, 0.5034]13 studies · 6950 participantsUngraded
Er:YAG laser (erbium-doped:yttrium-aluminum-garnet) vs Placebo (placebo laser or placebo agent) or no treatment
Outcome NR · Patients aged above 12 years with self-reported tooth hypersensitivity confirmed on clinical evaluation
Laser therapy for dentinal hypersensitivity (2021) · Cochrane
We did not find any eligible study to evaluate erbium:yttrium-aluminum-garnet (Er:YAG) or carbon dioxide (CO2) laser compared with placebo/no treatment.0 studiesNo studies
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 · Long term (follow-up 6 months), People diagnosed with periodontitis
Effect of periodontal treatments on blood pressure (2021) · Cochrane
MD -4.96 [-13.04, 3.13]2 studies · 227 participantsVery low
Electrical conductance devices (electronic caries monitor (ECM) and/or CarieScan Pro), used as an adjunct to clinical oral examination vs Reference standard: histology or enhanced visual examination (with or without radiographs)
Outcome NR · Teeth with previously applied restorations (secondary caries) or pit and fissure sealants; target condition =… · Up to 3 months between index test and reference standard (in vivo studies)
Electrical conductance for the detection of dental caries (2021) · Cochrane
No eligible studies. 'No included studies reported inclusion criteria of previously applied restorations or pit and fissure sealants' (a planned subgroup).0 studiesNo studies
Schwarz appliance vs No active treatment (control)
Upper incisors to maxilla (inclination, degrees) 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 0.33 [-2.26, 2.92]1 study · 28 participantsUngraded
Clear aligners (Invisalign / thermoformed aligners) vs Fixed appliances
Simplified gingival index (s-GI) · 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 -8.46 [-10.47, -6.45]1 studyUngraded
Intensive periodontal treatment (subgingival SRP with or without other periodontal treatment) vs Supra-gingival scaling
Clinical attachment level (CAL) · Adults (any age/sex) with chronic periodontitis (>=5 teeth remaining; PPD >4 mm), with or without hypertension · Long term, People diagnosed with periodontitis
Effect of periodontal treatments on blood pressure (2021) · Cochrane
MD -9.38 [-15.85, -2.91]1 studyUngraded
ARP with alloplast vs Extraction alone
Changes in bucco-lingual/palatal width of alveolar ridge (mm) · 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
Outcome not reported0 studiesNo studies
Visual examination (VE) 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 0.76 [0.11, 0.99]2 studiesUngraded
Poor / no tooth brushing habit vs Good tooth brushing habit
Dental caries (presence) · Individuals in East Africa assessed for dental caries · Community- and school-based populations, East Africa
Prevalence of Dental Caries and Associated Factors in East Africa, 2000-2020: Systematic Review and… (2021)
OR 1.967 [1.205, 3.211]10 studies · 4927 participantsUngraded
Visual examination (VE) vs Cavity preparation or biopsy (operative validation)
Diagnostic accuracy for occlusal caries detection at the caries detection level (D0 versus D1-D4) · Human permanent posterior teeth (premolars and molars) in patients, occlusal (pit-and-fissure) surfaces · in vivo
Systematic review and meta-analysis of diagnostic methods for occlusal surface caries. (2021)
Specificity 0.47 [0.26, 0.70]2 studiesUngraded
Conventional bitewing radiography (D-speed film) vs Cavity preparation or biopsy (operative validation)
Diagnostic accuracy for occlusal caries detection at the dentin caries detection level (D0-2 versus D3-4) · Human permanent posterior teeth (premolars and molars) in patients, occlusal (pit-and-fissure) surfaces · in vivo
Systematic review and meta-analysis of diagnostic methods for occlusal surface caries. (2021)
Specificity 0.75 [0.68, 0.82]2 studiesUngraded
Observed population vs Not applicable
Mean dmft/DMFT · School children aged 12-14 years in Dubai schools · Overall
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
MEAN 1.831 study · 2237 participantsUngraded
Lower parental (maternal/paternal) education vs Higher parental education
Dental caries · Healthy children and adolescents in the United Arab Emirates · UAE; schools/nurseries
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
Maternal education was not associated with children's caries in the Hashim et al. studies, whereas father's educational level was negatively associated with DMFT in Khadri et al. (secondary-aged children: -0.35, 95% CI…NRUngraded
Leukemia (oral health status) vs None (descriptive; compared by treatment location)
Oral health problems (mucositis, caries, candidiasis) · Children with leukemia in the United Arab Emirates · UAE
Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021)
Alnuaimi et al. reported a 60% prevalence of oral problems (mostly oral mucositis/ulceration, then dental caries and oral candidiasis) among children with leukemia; prevalence was not associated with age, gender,…1 studyUngraded
Laser fluorescence (DIAGNOdent 2095) vs Cavity preparation or biopsy (operative validation)
Diagnostic accuracy for occlusal caries detection at the dentin caries detection level (D0-2 versus D3-4) · Human permanent posterior teeth (premolars and molars) in patients, occlusal (pit-and-fissure) surfaces · in vivo
Systematic review and meta-analysis of diagnostic methods for occlusal surface caries. (2021)
DOR 35.90 [13.43, 96.00]2 studiesUngraded
Glass ionomer cement vs Amalgam
Success rate at 5 years · Patients needing retrograde filling in root canal therapy (orthograde root canal filling or retreatment not possible;… · 5 years
Materials for retrograde filling in root canal therapy (2021) · Cochrane
RR 1.00 [0.84, 1.20]1 studyUngraded