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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. Words match anywhere in the field.

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
TT+CC (homozygous) genotypes vs TC (heterozygous) genotype
Dental caries · Children (<18 years) with vs without dental caries · Over-dominant model (TT+CC vs TC), Permanent dentition
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.48 [1.07, 2.03]NRUngraded
Silver diamine fluoride (SDF) vs Sealants or resin infiltration
Dental pain or sensitivity · Children and adults (with or without carious lesions)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
No studies reported data for this outcome0 studiesNo studies
Silver diamine fluoride (SDF) vs Fluoride varnish
Primary caries prevention · Children and adults (with or without carious lesions) · 24 months, Permanent dentition (coronal)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
OR 0.95 [0.44, 2.05]1 study · 237 participantsVery low
TT genotype vs TC+CC genotypes
Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TC+CC), Real-time quantitative PCR genotyping
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 0.83 [0.54, 1.29]NRUngraded
Multistrand stainless steel wire vs Wires of other materials (conventional stainless steel, superelastic NiTi, thermoelastic NiTi)
Alignment rate · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 6 weeks to 6 months
Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane
Multistrand StSt versus other materials (conventional StSt, superelastic NiTi, thermoelastic NiTi); alignment rate not pooled due to clinical heterogeneity (Cobb 1998; Evans 1998; Quintao 2005; West 1995); results…4 studies · 281 participantsVery low
Prophylaxis (teeth cleaning) and CHX or iodine-NaF solution application in the dentition of women (mothers) vs Placebo
Child microbiological presence (mutans streptococci acquisition) · For interventions, pregnant women and mothers of infants in the first year of life; for outcomes, children up to 6…
Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane
Narrative (Dasanayake 1993; Dasanayake 2002): crude incidence of MS acquisition 36% greater in treatment children (not significant after adjustment); no significant difference in detectable S. mutans or mean time to…2 studiesUngraded
Serum 25(OH)D 50–75 nmol/l vs Serum 25(OH)D ≥ 75 nmol/l
Early childhood caries (ECC) · Preschool children ≤6 years, Asia and Europe · Asia and Europe
The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024)
OR 1.32 [1.17, 1.50]3 studies · 4996 participantsUngraded
Facemask with rapid maxillary expansion (RME) vs Reverse Twin Block with lip pads and rapid maxillary expander (RME)
Wits appraisal · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment
Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane
MD -1.85 [-3.18, -0.52]1 study · 26 participantsUngraded
Overweight/obesity (combined) vs Normal weight (eutrophic)
Dental caries prevalence (any DMFT), dichotomous · Brazilian children/adolescents (BMI classified by WHO 2007 percentile)
Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024)
OR 0.83 [0.35, 1.94]2 studies · 355 participantsVery low
Presence of oral Candida albicans vs Absence of oral Candida albicans
Early childhood caries (ECC) · Children aged ≤6 years (early childhood) · Exposure and outcome assessed concurrently (observational); children aged ≤6 years, Study quality (NOS): moderate
RETRACTED: Investigating the association between Candida albicans and early childhood dental caries: A… (2024)
OR 3.84 [2.24, 6.57]11 studiesUngraded
TT genotype vs TC+CC genotypes
Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TC+CC)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.21 [0.93, 1.56]5 studies · 1586 participantsUngraded
Disability (developmental, intellectual, or sensory) vs NA (single-group prevalence; no non-disabled comparison reported)
Moderate gingival inflammation / gingival health · Persons with disabilities (children and adults with autism, Down syndrome, cerebral palsy, hearing impairment, or… · Cross-sectional
Disabilities and Disparities in Oral Health-Related Quality of Life: A Systematic Review and Meta-Analysis… (2024)
Narrative synthesis (no pooled estimate). Moderate-to-severe gingival inflammation up to about 60% among PWDs (abstract). Alkahtani 2019 (hearing-impaired adults, single-arm): 60.1% had moderate gingival inflammation…NRUngraded
Higher BMI (continuous / per-unit increment) vs Lower BMI (continuous reference / per 1 kg/m2 decrement)
Dental caries in children · Children (approx. 4-18 years) · Linear dose-response (GLST, per 1 kg/m2 BMI increment)
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.01 [1.00, 1.03]16 studiesUngraded
Intervention NR
Fluoride ion release · nCaF2-containing orthodontic adhesive (Yi 2024 [35]); significant increase up to 56 days vs control
Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024)
no estimate extracted1 studyUngraded
Facemask (RME) or modified facemask vs Surgically-anchored appliance (miniscrews or miniplates)
ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment
Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane
MD -0.35 [-0.78, 0.07]4 studies · 143 participantsLow
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight)
Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Country population: small
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.31 [0.95, 1.81]7 studiesUngraded
Adhesive flash-free ceramic brackets vs Adhesive precoated ceramic brackets
Enamel demineralization (QLF ΔF) · Patients undergoing fixed orthodontic treatment · Baseline to debonding
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
ΔF values (T0-debonding) were not statistically significantly different between the groups.1 study · 50 participantsUngraded
Intervention NR
Spontaneous space closure · Maxilla: M2 Demirjian E-F vs G-H
Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024)
OR 8.01 studyUngraded
Pulpotomy (full or partial) vs None (single-arm success proportion)
Overall success (composite of clinical and radiographic success) · Permanent teeth with carious pulp exposure · 24 months, 24-month follow-up
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
Proportion 0.902NRUngraded
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control)
Bacterial plaque index · Children and/or adolescents (<18 years) without background systemic disease · follow-up: mean 2.3 months, Overall (all presentations pooled)
Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024)
MD 0.21 [-0.55, 0.96]4 studies · 171 participantsVery low
Silver diamine fluoride (SDF) vs Fluoride varnish
Primary caries prevention · Children and adults (with or without carious lesions) · 12 months, Primary dentition
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
MD 0.00 [-0.26, 0.26]1 study · 434 participantsLow
Intralesional steroid injections vs Alternative medicinal treatments
Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months
Interventions for managing oral submucous fibrosis (2024) · Cochrane
MD 8.61 [-4.52, 21.74]3 studies · 98 participantsVery low
Occlusal splint vs Another occlusal splint with a different mechanism of action
Participant satisfaction or quality of life · People with temporomandibular disorders (TMD) · Short term (3 months), Mixed TMD
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
MD -2.29 [-3.13, -1.45]1 study · 40 participantsUngraded
TT+CC (homozygous) genotypes vs TC (heterozygous) genotype
Dental caries · Children (<18 years) with vs without dental caries · Over-dominant model (TT+CC vs TC)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.33 [1.06, 1.67]6 studies · 1986 participantsUngraded
Silver diamine fluoride (SDF) plus fluoride varnish vs Sealants plus fluoride varnish (with or without restorations)
Secondary prevention of caries · Children and adults (with or without carious lesions)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
No studies reported data for this outcome in this comparison0 studiesNo studies
Silver diamine fluoride (SDF; 38% in most trials, 30% in three) vs Nano-silver fluoride (NSF; with or without green tea extract)
Caries arrestment at the tooth level · Children and adults with active dental caries (aged 1-50; mostly preschool/school children with primary dentition) · 6 to 12 months, SDF vs NSF
The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024)
OR 1.47 [0.93, 2.33]2 studies · 408 participantsUngraded
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight)
Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Adjustment for age: no
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.68 [1.29, 2.18]10 studiesUngraded
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT
Change in gingival recession (REC) · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment · 3 months (change from baseline)
Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane
MD -0.01 [-0.06, 0.05]13 studies · 284 participantsUngraded
Teledentistry diagnosis using DSLR or smartphone extra-oral photographs vs Visual or clinical examination
Sensitivity for dental caries diagnosis · Children and adults with primary or permanent dentition · Overall
Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024)
Sensitivity Overall 48% to 98.3% across 13 studies; sensitivity is lesion-stage dependent: Kohara reported <40% for initial/moderate caries (75-100% for extensive) and early enamel lesions were less sensitive13 studiesUngraded
Package of oral health education/promotion including oral hygiene advice for pregnant women, mothers, infants and young children, plus dietary and feeding practice advice for infants and young children vs Standard care
d1-4 efs · For interventions, pregnant women, mothers or other caregivers of infants in the first year of life; for outcomes,…
Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane
Veronneau 2010 (narrative): at 5-6 yrs mean d1-4efs 4.9 (test) vs 6.8 (control) (p < 0.001).1 studyUngraded
AA+GG (homozygous) genotypes vs AG (heterozygous) genotype
Dental caries · Children (<18 years) with vs without dental caries · Over-dominant model (AA+GG vs AG)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.04 [0.64, 1.70]3 studies · 855 participantsUngraded
Extraction of the permanent first molar vs None (single-group prevalence)
Spontaneous space closure · Children and adolescents (<18 years) after extraction of a permanent first molar before eruption of the permanent… · Until eruption of the permanent second molar (median follow-up 4.0 years), Overall (both jaws)
Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024)
Prevalence 61.6 [50.2, 71.9]13 studies · 1787 participantsUngraded
TT genotype vs TC+CC genotypes
Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TC+CC), Mixed dentition
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 0.73 [0.43, 1.24]NRUngraded
Intervention NR
Dental caries (early childhood caries) · Narrative single study (Ganesh 2022): BF in early morning sleep hours
Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024)
AOR 3.71 studyUngraded
Clearfil Protect Bond vs Transbond XT conventional adhesive
White spot lesion rate and volume · Patients undergoing fixed orthodontic treatment · 8 weeks after bonding
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
There was no significant difference among the WSL rates of the Clearfil, Opal Seal, and Transbond XT adhesives (p > 0.05).1 study · 15 participantsUngraded
Silver diamine fluoride (SDF) plus fluoride varnish vs Sealants plus fluoride varnish (with or without restorations)
Primary caries prevention · Children and adults (with or without carious lesions)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
No studies reported data for this outcome in this comparison0 studiesNo studies
Transbond XT with 1% chitosan and 1% TiO2 nanoparticles vs Transbond XT adhesive
Enamel mineral content · Patients undergoing fixed orthodontic treatment · 1 day, 2 months, and 6 months after bonding
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
There were no significant differences in enamel mineral content between the experimental group and control group at all time points.1 study · 24 participantsUngraded
Prenatal vitamin D level ≤35 nmol/L vs Normal or sufficient prenatal vitamin D level
Dental caries · Children aged 2 to 8 years · Maternal pregnancy to child age 2 to 8 years, Vitamin D threshold ≤35 nmol/L
Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024)
OR 1.36 [1.20, 1.53]9 studiesUngraded
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence)
Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · Region: Europe
A systematic review and meta-analysis on early-childhood-caries global data. (2024)
MEAN 2.26 [0.69, 3.82]11 studiesUngraded
Health service and/or policy intervention designed to modify access to oral health information or services for pregnant women, new mothers or other primary caregivers vs Standard care (or any comparator)
Outcome NR · For interventions, pregnant women, mothers or other caregivers of infants in the first year of life; for outcomes,…
Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane
No trials evaluated policy or health service interventions designed to modify access to oral health information or services.0 studiesNo studies
Mineral trioxide aggregate (MTA) vs Platelet-rich fibrin (PRF)
Overall success (composite of clinical and radiographic success) · Permanent teeth with carious pulp exposure · >=12 months
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
OR 1.02 [0.43, 2.43]3 studies · 109 participantsUngraded
Slum setting vs Non-slum urban setting
Self-perceived oral health · Adults in LMIC urban and slum settings
Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024)
no estimate extracted6 studiesUngraded
Experimental adhesive containing ammonium-based methacrylate monomer (MADQUAT) vs Conventional/control orthodontic adhesive (e.g., Transbond XT) or negative control
Enamel remineralization / carious lesion development · Human enamel specimens around orthodontic brackets (in vitro) · biofilm cariogenic challenge 5 days, Overall
Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024)
A study using an orthodontic adhesive containing ammonium-based methacrylate showed significant remineralization power compared with control adhesives [37].1 studyUngraded
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Dental caries (prevalence) · Adults · Overall
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 1.57 [1.20, 2.07]10 studiesUngraded
Breastfeeding for <6 months vs Breastfeeding for ≥6 months
Dental caries (early childhood caries) · Preschool children (<6 years) · Case-control studies
Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024)
OR 0.53 [0.41, 0.67]2 studies · 1201 participantsUngraded
Superelastic NiTi arch wire vs Thermoelastic NiTi arch wire
Pain day 1 · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 7 days
Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane
MD 6.96 [1.82, 12.10]3 studies · 94 participantsModerate
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight)
Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Region: American countries
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.28 [0.91, 1.81]7 studiesUngraded
SDF (given at a particular frequency, concentration, or duration) vs SDF (given at a different frequency, concentration, or duration)
Secondary prevention of caries · Children and adults (with or without carious lesions) · 30 months, Primary dentition
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
MD -0.10 [-0.61, 0.41]1 study · 203 participantsVery low
Overweight/obesity (combined) vs Normal weight (eutrophic)
Dental caries prevalence (any dmft), dichotomous · Brazilian children in primary dentition (BMI classified by CDC 2000 growth charts)
Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024)
OR 0.83 [0.45, 1.54]2 studies · 826 participantsVery low
Intralesional dexamethasone injections vs Placebo injections
Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months
Interventions for managing oral submucous fibrosis (2024) · Cochrane
MD -46.00 [-53.44, -38.56]1 study · 25 participantsVery low