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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
Overweight/obesity (combined) vs Normal weight (eutrophic)
Dental caries prevalence (any DMFT), dichotomous · Brazilian children/adolescents in permanent dentition (BMI classified by WHO 2007 Z-score)
Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024)
OR 0.93 [0.78, 1.12]2 studiesLow
Abdominal dermal fat graft vs Nasolabial flap
Maximal mouth opening (interincisal distance) · 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 -14.87 [-19.93, -9.81]1 study · 30 participantsVery low
Buccal fat pad graft vs Extended nasolabial flap
Maximal mouth opening (interincisal distance) · 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 6.00 [-11.36, 23.36]1 study · 8 participantsVery low
Thermoelastic copper NiTi (CuNiTi) arch wire vs Conventional NiTi arch wire
Alignment rate · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 4 weeks
Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane
MD 0.10 [-0.95, 1.15]1 study · 66 participantsVery low
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Root caries · Adults · Root caries
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 2.10 [1.03, 4.29]4 studiesUngraded
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population
Use of toothbrush and toothpaste for mouth cleaning · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Slum/disadvantaged/rural vs non-slum/urban
Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024)
Eleven studies addressed practices; toothbrush and toothpaste were the commonest cleaning method but their use was lower among slum/disadvantaged/rural groups than non-slum/urban groups (e.g., Osuh 78% slum vs 94%…11 studiesUngraded
Intervention NR
Dental caries (early childhood caries) · Narrative single study (Ganesh 2022): BF during sleep
Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024)
AOR 6.51 studyUngraded
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT
Outcome NR · Adults (> 18 years) with peri-implant mucositis, receiving supportive treatment
Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane
Planned comparison; no studies met the inclusion criteria. The review found only one study of peri-implant disease (peri-implant mucositis, active treatment) and no studies including people with peri-implantitis…NRNo studies
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: Asia-Oceania
A systematic review and meta-analysis on early-childhood-caries global data. (2024)
MEAN 3.87 [2.84, 4.91]30 studiesUngraded
TT genotype vs TC+CC genotypes
Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TC+CC), Permanent dentition
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.36 [0.89, 2.08]NRUngraded
Single preoperative dose of systemic antibiotics (clindamycin 600 mg), total chemo-mechanical debridement and root filling vs Matched placebo, total chemo-mechanical debridement and root filling
Swelling at 7 days · Adults with symptomatic apical periodontitis (no signs of spreading infection or systemic involvement) · 7 days
Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane
RR 0.50 [0.10, 2.56]1 study · 72 participantsLow
Consumption of xylitol chewing gum by women (mothers) vs Consumption of CHX/xylitol gum by women, or CHX varnish applied to women's dentition
Mother microbiological presence (mutans streptococci colonisation level, CFU/mL) · 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
MD 0.50 [0.15, 0.85]1 study · 126 participantsUngraded
Prenatal vitamin D deficiency measured at 6 to 38 gestational weeks vs Normal or sufficient prenatal vitamin D level
Dental caries · Children aged 2 to 8 years · Maternal gestational weeks 6 to 38, Vitamin D measurement at 6 to 38 gestational weeks
Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024)
OR 1.32NRUngraded
Facemask vs Untreated control (no treatment)
ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · 3-year follow-up
Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane
MD 1.40 [0.43, 2.37]1 study · 63 participantsModerate
Vasodilators (isoxsuprine, xanthinol nicotinate) vs Placebo or no active treatment
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 -51.02 [-72.85, -29.20]2 studies · 85 participantsVery low
Facemask with rapid maxillary expansion (RME) vs Pushing Splints
Adverse effects · 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
Galeotti 2021: occasional skin irritation on the chin and three appliance breakages (one facemask, two Pushing Splints).1 study · 42 participantsUngraded
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence)
Dental caries, prevalence · Primary school children in Ethiopia · Sampling technique: simple random sampling
Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024)
Prevalence 42 [35, 49]4 studies · 1421 participantsUngraded
Full pulpotomy vs Partial pulpotomy
Overall success (composite of clinical and radiographic success) · Mature permanent teeth with symptomatic irreversible pulpitis and carious pulp exposure · >=12 months
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
OR 2.16 [0.92, 5.07]3 studiesUngraded
Silver diamine fluoride (SDF) vs Sealants or resin infiltration
Primary caries prevention · Children and adults (with or without carious lesions) · Primary dentition
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
No studies reported data in this dentition type0 studiesNo studies
Unilateral extraction of the mandibular first permanent molar vs Bilateral extraction of the mandibular first permanent molars
Midline deviation of the mandibular arch · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible
Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024)
OR 11.6 [1.9, 70.3]1 studyUngraded
Topical curcumin gel vs Topical aloe vera gel
Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months
Interventions for managing oral submucous fibrosis (2024) · Cochrane
MD 16.00 [7.21, 24.79]1 study · 60 participantsVery low
Consumption of xylitol chewing gum by women (mothers) vs Consumption of CHX/xylitol gum by women, or CHX varnish applied to women's dentition
defs index score (categories) · 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
Thorild 2003 defs score categories (very low-certainty): 1-3 defs RR 0.48 (95% CI 0.15 to 1.54); 3-4 defs RR 0.85 (95% CI 0.18 to 3.98); >=5 defs RR 0.28 (95% CI 0.01 to 6.78); 96 participants.1 study · 96 participantsVery low
Facemask (RME) or modified facemask vs Surgically-anchored appliance (miniscrews or miniplates)
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 0.50 [-1.27, 2.27]1 study · 43 participantsUngraded
Facemask with rapid maxillary expansion (RME) vs Pushing Splints
Overjet · 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 0.80 [-0.37, 1.97]1 study · 42 participantsUngraded
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence)
Early childhood caries (ECC) prevalence (%, dmft>0) · Children younger than 71 months (under 6 years) · Life expectancy: 71-75 years
A systematic review and meta-analysis on early-childhood-caries global data. (2024)
Prevalence 62NRUngraded
Vasodilators (isoxsuprine, xanthinol nicotinate) vs Placebo or no active treatment
Adverse effects · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF)
Interventions for managing oral submucous fibrosis (2024) · Cochrane
Adverse effects (any): 0 placebo vs 14 minor (transient flushing and upper trunk warmness); 85 (2); no GRADE rating.2 studies · 85 participantsUngraded
Mineral trioxide aggregate (MTA) vs Calcium hydroxide (CH)
Overall success (composite of clinical and radiographic success) · Permanent teeth with carious pulp exposure · >=12 months, Partial pulpotomy
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
OR 2.81 [1.38, 5.74]NRUngraded
Maternal smoking during pregnancy vs No maternal smoking during pregnancy
Dental caries in children · Children of mothers assessed for smoking status during pregnancy (early childhood dental caries) · Exposure during pregnancy; caries assessed in early childhood, Overall (all 12 studies pooled)
Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024)
OR 1.774 [1.554, 2.026]12 studies · 90405 participantsUngraded
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 bleeding on probing (BOP) · Adults (> 18 years) with recurrent periodontitis, receiving supportive (maintenance) periodontal care · 3 months (change from baseline)
Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane
MD 2.38 [-1.34, 6.10]5 studies · 231 participantsUngraded
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
Intolerance to spicy food (participant-reported proxy) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF)
Interventions for managing oral submucous fibrosis (2024) · Cochrane
OR 0.02 [0.00, 0.43]1 study · 100 participantsUngraded
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control)
Gingival index · Children and/or adolescents (<18 years) without background systemic disease · follow-up: mean 3.07 months, Overall (all presentations pooled)
Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024)
MD 0.04 [-0.18, 0.27]3 studies · 144 participantsLow
Grape seed extract or grape seed flavonoid fractions vs No extract or vehicle control; other antimicrobial agents
Bacterial growth inhibition · Streptococcus mutans cultures and biofilms
Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024)
no estimate extracted5 studiesUngraded
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint)
Muscle pain when chewing · People with temporomandibular disorders (TMD) · Short term (3 months), Disc displacement without reduction (DDwoR)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
MD -1.97 [-2.37, -1.57]1 study · 84 participantsVery low
Postoperative systemic antibiotics (phenoxymethylpenicillin/penicillin VK, 7-day course), partial or total chemo-mechanical debridement and analgesics vs Matched placebo, partial or total chemo-mechanical debridement and analgesics
Pain at 72 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 72 hours
Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane
MD 0.08 [-0.38, 0.54]2 studies · 61 participantsVery low
Facemask vs Untreated control (no treatment)
Self-esteem (Oral Aesthetic Subjective Impact Score, OASIS) · 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 -4.00 [-7.40, -0.60]1 study · 69 participantsUngraded
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate)
Association between patient age and number of ICLs · Patients (permanent dentition) during or after fixed orthodontic treatment with fixed (multibracket) appliances · During or after fixed orthodontic treatment, By patient age (subgroup meta-analysis; no significant association)
Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024)
No significant association found between patient age and the number of ICLs (meta-regression / subgroup analysis)NRUngraded
Absence of toothpaste use vs Toothpaste use
Dental caries · Primary school children in Ethiopia
Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024)
OR 1.42 [-1.278, 4.109]NRUngraded
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 bleeding on probing (BOP) · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment · 6 months (change from baseline)
Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane
MD 5.72 [1.62, 9.81]5 studies · 171 participantsVery low
Reduction in previous year's academic score vs No reduction in academic score
Reduction in previous year's academic score · Primary school children in Ethiopia
Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024)
OR 5.51 [1.952, 9.066]NRUngraded
Facemask vs Untreated control (no treatment)
ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · 6-year follow-up
Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane
MD 0.70 [-0.74, 2.14]1 study · 65 participantsLow
Occlusal splint vs Acupuncture
Discomfort · People with temporomandibular disorders (TMD)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
Listed in Summary of findings 5 as 'Not reported'; this outcome was not reported by any included study for this comparison.0 studiesNo studies
Second molar at Demirjian stage F-G at extraction vs Second molar at Demirjian stage D-E at extraction
Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible
Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024)
OR 0.68 [0.28, 1.66]4 studiesUngraded
Superelastic NiTi arch wire vs Conventional (stabilised) NiTi arch wire
Pain day 1 · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 3 to 7 days
Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane
MD 0.29 [-0.52, 1.10]2 studies · 142 participantsLow
Occlusal splint vs Pharmacological therapy
Muscle pain at mastication · People with temporomandibular disorders (TMD)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
Listed in Summary of findings 6 as 'Not reported'; this outcome was not reported by any included study for this comparison.0 studiesNo studies
Occlusal splint vs Another occlusal splint with a different mechanism of action
Joint pain at rest · People with temporomandibular disorders (TMD) · Long term (12 months), Disc displacement with reduction (DDwR)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
RR 7.00 [0.41, 120.16]1 study · 20 participantsVery low
Intervention NR
Overall success (composite of clinical and radiographic success) · Partial pulpotomy, mature teeth
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
Proportion 0.842 [0.745, 0.921]6 studiesUngraded
Superelastic NiTi arch wire vs Thermoelastic NiTi arch wire
Time to alignment · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 16 weeks
Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane
MD 0.5 [0.21, 0.79]1 study · 32 participantsLow
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), Real-time quantitative PCR genotyping
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.52 [1.10, 2.10]NRUngraded
Chin cup vs Untreated control (no treatment)
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 1.96 [1.58, 2.34]1 study · 50 participantsUngraded
Bone-anchored intermaxillary traction (BAIMT) vs Removable mandibular retractor (RMR)
Adverse effects / patient-reported (pain, self-confidence) · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · During treatment
Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane
Majanni 2016: BAIMT associated with higher pain early in treatment than RMR (P<0.001); RMR negatively impacted self-confidence more than BAIMT at all time points (P<0.001).1 study · 38 participantsUngraded