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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. Words match anywhere in the field.

Limit to evidence status or GRADE (optional)

75,239 questions in 5,342 reviews

current versions
No studies 15,213 · 20.2%Ungraded 10,323 · 13.7%Very low 17,528 · 23.3%Low 17,951 · 23.9%Moderate 11,190 · 14.9%High 3,034 · 4%

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
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, Study region: Europe
Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024)
OR 1.67 [1.40, 1.99]4 studiesUngraded
Children with severe early childhood caries (S-ECC) vs Caries-free children
Serum 25-hydroxyvitamin D level · Preschool children ≤6 years, Asia · Asia
The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024)
MD -19.25 [-20.75, -17.76]NRUngraded
Facemask (RME) or modified facemask vs Other non-surgical orthodontic treatments (mini maxillary protractor, Pushing Splints, modified tandem, Reverse Forsus, reverse Twin Block, reverse chin cup, tongue appliance, Frankel III)
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 0.11 [-0.54, 0.77]8 studies · 285 participantsVery low
Periodontitis / periodontal disease (history or clinical diagnosis) vs No periodontitis (individuals without periodontal disease)
Oral cancer (OC) · Adults in case-control studies of oral cancer; people assessed for periodontitis · Not specified, Overall (random-effects pooled estimate)
Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024)
OR 2.94 [2.13, 4.07]8 studies · 6927 participantsLow
Silver diamine fluoride (SDF) vs Placebo or no treatment
Caries arrest · Children and adults (with or without carious lesions) · 36 months, Permanent dentition (coronal)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
MD 0.20 [0.00, 0.40]1 study · 373 participantsVery low
Extraction at patient age 11-12 years vs Extraction at patient age 8-10 years
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 0.29 [0.11, 0.81]2 studiesUngraded
Pentoxifylline vs Multivitamin
Maximal mouth opening (interincisal distance) · 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
Rajendran 2006 (pentoxifylline 14 vs multivitamins 15): reported increased interincisal distance in the pentoxifylline group but no baseline data, so change could not be determined; excluded from meta-analysis.1 study · 29 participantsUngraded
Second molar at Nolla developmental stage 6-7 at extraction vs Second molar at later Nolla stages 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 55.1 [3.0, at least 100.0]1 studyUngraded
Oxitard (antioxidant) vs Aloe vera gel
Maximal mouth opening (interincisal distance) · 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 9.40 [8.52, 10.28]1 study · 120 participantsLow
Cesarean section delivery vs Vaginal delivery
Early childhood caries (ECC) · Children aged <6 years · Study quality (NOS): Moderate
RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024)
OR 1.10 [0.75, 1.61]12 studiesUngraded
TiO2-modified composite (1 wt.%) vs Control composite in contralateral quadrant
Streptococcus mutans population · Patients undergoing fixed orthodontic treatment · 1 to 6 months after bonding
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
No statistically significant difference between the S. mutans populations on the control and test sides at any time point.1 study · 40 participantsUngraded
Facemask (RME) or modified facemask vs Surgically-anchored appliance (miniscrews or miniplates)
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 -0.40 [-1.30, 0.50]1 study · 43 participantsVery low
Dietary advice on how to achieve a healthy diet for infants (tailored advice focused on a diet low in saturated fat and cholesterol intake) vs Standard care
Mother self-reported oral health behaviours · 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
Data from Lapinleimu 1995 on mother oral health behaviour (other data) showed some evidence of benefit in favour of the intervention.1 studyUngraded
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy)
Recurrence rate · People with temporomandibular disorders (TMD)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
Listed in Summary of findings 3 as 'Not reported'; this outcome was not reported by any included study for this comparison.0 studiesNo studies
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate)
Association between orthodontic treatment duration and ICLs prevalence · Patients (permanent dentition) during or after fixed orthodontic treatment with fixed (multibracket) appliances · During or after fixed orthodontic treatment, By orthodontic treatment duration (subgroup meta-analysis; positive association, P=.01)
Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024)
Prevalence of ICLs positively associated with orthodontic treatment duration (meta-regression, P=.01); effect size/slope not available (Fig. 6a image not provided)NRUngraded
SDF (given at a particular frequency, concentration, or duration) vs SDF (given at a different frequency, concentration, or duration)
Aesthetics · Children and adults (with or without carious lesions) · 24 months, Children
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
1 study (119 children) reported that 45% parents were satisfied with child's dental appearance (data not reported by study group)1 study · 119 participantsVery low
Cesarean section delivery vs Vaginal delivery
Early childhood caries (ECC) · Children aged <6 years · Sample size: <300
RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024)
OR 1.09 [0.64, 1.86]13 studiesUngraded
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control)
Number of dental caries (carious pieces) · Adolescents (12-18 years) without background systemic disease · Population: adolescents (vs children; p-interaction=0.02)
Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024)
MD -0.60 [-0.92, -0.28]NRUngraded
Breastfeeding promotion and support (e.g. individually tailored home-based peer counselling on the importance of breastfeeding, with advice and support for healthy breastfeeding) vs Standard care
Caries presence in primary teeth · For interventions, pregnant and lactating women; for outcomes, children up to 6 years of age · Children assessed at 5-6 yrs
Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane
RR 0.96 [0.89, 1.03]2 studies · 1148 participantsLow
Facemask with rapid maxillary expansion (RME) vs Facemask with alternating rapid maxillary expansion and constriction (Alt-RAMEC)
Overjet · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion)
Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane
SoF5 (Facemask (Alt-RAMEC) vs facemask (RME)): Overjet - Not measured.0 studiesNo studies
High-frequency sugar consumption (three or more times daily) vs Low sugar intake (fewer than three times daily)
Dental caries experience in primary dentition (early childhood caries) · Nigerian children with primary dentition (approximately 6 months to 5 years) · Primary dentition
A systematic review and meta-analysis of the association between sugar intake and dental caries in Nigeria. (2024)
OR 1.13 [0.23, 5.44]2 studiesUngraded
Clearfil Protect Bond antibacterial fluoride-releasing primer vs Transbond XT conventional primer
White spot lesion incidence · Patients undergoing fixed orthodontic treatment · Before and after orthodontic treatment
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
The incidence of WSLs in the Clearfil (CF) group was 8.03%, while in the Transbond (TB) group, it was 9.24% with no significant difference (p = 0.82).1 study · 35 participantsUngraded
Silver diamine fluoride (SDF) vs Glass ionomer cement (GIC) plus fluoride varnish
Aesthetics · 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
NiTi arch wire of one cross-sectional size vs NiTi arch wire of a different cross-sectional size
Root resorption · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)
Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane
Root resorption: not reported0 studiesNo studies
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Mean DMFT (decayed, missing, filled teeth) · Adults · Overall
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
WMD 0.87 [-0.03, 1.76]4 studiesUngraded
Pulpotomy (full or partial) vs None (single-arm success proportion)
Overall success (composite of clinical and radiographic success) · Permanent teeth with carious pulp exposure · >=12 months, Normal pulp/reversible pulpitis
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
Proportion 0.920 [0.879, 0.954]NRUngraded
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: large
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.56 [1.09, 2.21]9 studiesUngraded
Silver diamine fluoride (SDF) vs Sealants or resin infiltration
Secondary prevention of caries · Children and adults (with or without carious lesions) · 24 months, Primary dentition (coronal)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
OR 2.76 [0.67, 11.43]1 study · 75 participantsUngraded
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): good
RETRACTED: Investigating the association between Candida albicans and early childhood dental caries: A… (2024)
OR 5.32 [2.89, 9.80]7 studiesUngraded
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint)
Discomfort · People with temporomandibular disorders (TMD)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
Listed in Summary of findings 1 as 'Not reported'; this outcome was not reported by any included study for this comparison. Discomfort was not reported in any included study across the whole review.0 studiesNo studies
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, Dental examination: Visual/tactile examination
Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024)
OR 1.48 [1.26, 1.74]4 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) · GNI <$5000
A systematic review and meta-analysis on early-childhood-caries global data. (2024)
MEAN 4.64 [3.38, 5.91]19 studiesUngraded
Silver diamine fluoride (SDF) plus fluoride varnish vs Sealants plus fluoride varnish (with or without restorations)
Caries arrest · Children and adults (with or without carious lesions) · 24 months, Mixed dentition (coronal)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
MD 0.11 [-0.01, 0.22]1 study · 413 participantsLow
Facemask with rapid maxillary expansion (RME) vs Facemask with alternating rapid maxillary expansion and constriction (Alt-RAMEC)
A-Nasion perpendicular (A-NPerp) · 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 1.13 [0.23, 2.03]1 study · 34 participantsUngraded
Opal Seal fluoride-releasing primer vs Conventional Transbond XT primer
DIAGNOdent white spot lesion measurement · Patients undergoing fixed orthodontic treatment · During orthodontic treatment
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
Opal Seal group showed fewer WSLs compared to the Transbond group, with initial demineralization rates of 1.3% and 3.9%, and caries lesion rates of 0.2% and 1.3%, respectively (p <0.03).1 study · 56 participantsUngraded
Slum residence vs Non-slum urban residence
Periodontal pocket (odds), slum vs non-slum residence · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Slum vs non-slum urban (Osuh 2022, Nigeria)
Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024)
OR 1.50 [1.13, 1.98]1 study · 1357 participantsUngraded
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Dental caries (prevalence) · Adults · Standard periodontitis definition
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 1.62 [1.20, 2.18]8 studiesUngraded
Occlusal splint vs Another occlusal splint with a different mechanism of action
Self-reported joint pain when chewing · People with temporomandibular disorders (TMD)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
Listed in Summary of findings 2 as 'Not reported'; this outcome was not reported by any included study for this comparison.0 studiesNo studies
Male sex vs Female sex
Dental caries risk · Institutionalized orphan children · Overall (pooled)
Caries in orphan children: prevalence and determinants-a systematic review and meta-analysis. (2024)
RR 1.02 [0.96, 1.08]5 studies · 2750 participantsVery low
Grape seed extract or grape seed flavonoid fractions vs No extract or vehicle control; other antimicrobial agents
Biofilm morphology · Streptococcus mutans cultures and biofilms
Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024)
no estimate extracted2 studiesUngraded
Silver diamine fluoride (SDF) vs Restoration (restorative treatment)
Aesthetics · Children and adults (with or without carious lesions) · 6 to 12 months, Children
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
Cleary 2022 reported no significant differences (P > 0.05) in parental acceptability, satisfaction, and preference between treatments at 6 and 12 months; at 12 months children in the restoration arm felt happier with…1 studyVery low
Facemask with rapid maxillary expansion (RME) vs Tongue appliance
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 -0.60 [-1.41, 0.21]1 study · 47 participantsUngraded
Grape seed extract (GSE) and its proanthocyanidin fractions vs Untreated or vehicle control (some studies vs positive antimicrobial controls, e.g. chlorhexidine/fluoride)
Bacterial adhesion (inhibition) · Streptococcus mutans (in vitro cultures and biofilms)
Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024)
GSE inhibited S. mutans adhesion to hydroxyapatite by 81.5% (polymeric PAC, 0.125 mg/mL) vs 25% for dealcoholized wine (Daglia); adhesion decreased at MIC 0.5 mg/mL (Smullen).2 studiesUngraded
Opal Seal fluoride-releasing primer vs Conventional Transbond XT primer
Photographic white spot lesion severity · Patients undergoing fixed orthodontic treatment · During orthodontic treatment
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
WSL severity in digital photographs: no significant difference between the two groups (p >0.05).1 study · 56 participantsUngraded
Facemask with rapid maxillary expansion (RME) vs Modified tandem appliance
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 0.25 [-0.39, 0.89]1 study · 32 participantsUngraded
Resin-modified glass-ionomer cement (RM-GIC) for bracket bonding vs Conventional composite resin adhesive (Transbond XT)
New white spot lesion incidence (and first-time bracket bond failure) · Patients undergoing fixed orthodontic (fixed appliance) treatment (adolescents and adults, ages 12 to 35) · During fixed appliance treatment
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
Benson 2019 (1 multicenter single-blind RCT, 197 patients): no difference in the proportion of patients with new WSLs or first-time bracket failures between RM-GIC and resin adhesive (p>0.05). No meta-analysis performed.1 study · 197 participantsUngraded
Superelastic NiTi arch wire vs Thermoelastic NiTi arch wire
Root resorption (reduction in root length) · 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 -0.05 [-0.14, 0.04]2 studies · 52 participantsVery low
Pulpotomy (full or partial) vs None (single-arm success proportion)
Overall success (composite of clinical and radiographic success) · Permanent teeth with carious pulp exposure · 12 months, 12-month follow-up
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
Proportion 0.856NRUngraded
Silver diamine fluoride (SDF) plus fluoride varnish vs Sealants plus fluoride varnish (with or without restorations)
Aesthetics · 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) vs Atraumatic restorative treatment (ART) with glass ionomer cement (GIC) or glass ionomer material
Secondary prevention of caries · Children and adults (with or without carious lesions) · Primary and permanent dentition
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
No studies reported this outcome0 studiesNo studies