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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
Grape seed extract (GSE) and its proanthocyanidin fractions vs Untreated or vehicle control (some studies vs positive antimicrobial controls, e.g. chlorhexidine/fluoride)
Gtf activity · 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 glucosyltransferase activity 43.9%, rising to 65.7% when combined with amine fluoride (Furiga).1 studyUngraded
Facemask vs Untreated control (no treatment)
Overjet · 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 1.30 [-0.16, 2.76]1 study · 65 participantsLow
Surgical miniplates with facemask vs Surgical miniplates with Class III elastics
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 0.02 [-1.23, 1.27]1 study · 20 participantsUngraded
Fluoride-releasing primers/adhesives (Opal Seal; Clearfil Protect Bond) vs Conventional primer/adhesive (Transbond XT)
White spot lesions / enamel demineralization (photographic scoring, DIAGNOdent, micro-CT) · Patients undergoing fixed orthodontic (fixed appliance) treatment (adolescents and adults, ages 12 to 35) · 8 weeks to full treatment (to debonding)
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
Three non-randomized studies (Comert 2020 n=56; Oz 2019 n=35; Oz 2017 n=15) showed no consistent clinical advantage. Comert: no significant difference in photographic WSL severity or area, although DIAGNOdent favored…3 studies · 106 participantsUngraded
Orthodontic adhesive containing quaternary ammonium resin monomer + 40% n-ACP vs Conventional/control orthodontic adhesive (e.g., Transbond XT) or negative control
Calcium and phosphate ion release · Human enamel specimens around orthodontic brackets (in vitro) · up to 42 days, Overall
Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024)
One study using an experimental quaternary ammonium resin monomer + 40% n-ACP adhesive reported a significant increase of calcium and phosphate ion release up to 42 days compared with the control group [33].1 studyUngraded
Number of missing teeth (per additional tooth) vs One fewer missing tooth
Oral cancer (OC) · Adults in case-control studies of oral cancer · Not specified, Missing teeth (per tooth)
Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024)
OR 0.96 [0.92, 1.01]2 studiesUngraded
Intervention NR
Dental caries prevalence in children · Meta-regression adjusted estimate
Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024)
Proportion 0.21 [0.16, 0.26]NRUngraded
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) · 6-year follow-up
Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane
MD -2.20 [-7.31, 2.91]1 study · 65 participantsUngraded
Pentoxifylline vs Placebo or no active treatment
Difficulty in speech (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 0.20 [0.08, 0.48]1 study · 106 participantsUngraded
Started toothbrushing with fluoride toothpaste before 24 months (earlier start) vs Started after 24 months (later start)
Fluorosis (percentage prevalence in permanent teeth) · Children exposed to topical fluoride when under 6 years old; fluorosis assessed in permanent teeth at 6 to 18 years · Fluorosis assessed when most permanent teeth of interest had erupted (6 to 18 years)
Topical fluoride as a cause of dental fluorosis in children (2024) · Cochrane
OR 2.25 [1.19, 4.23]6 studies · 1223 participantsVery low
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, Sample size: >3000
Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024)
OR 2.18 [2.07, 2.31]2 studiesUngraded
Salivary Actinobacillus level (high) vs Not specified
Salivary S. mutans level · Humans with salivary bacteria measured · Overall
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 2.39 [1.00, 5.71]1 studyUngraded
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, Sample collection: oral swab
RETRACTED: Investigating the association between Candida albicans and early childhood dental caries: A… (2024)
OR 9.55 [2.17, 42.01]2 studiesUngraded
Intervention NR
Change in prevalence of salivary Streptococcus sobrinus · Single study (Stsepetova et al. 2019), erythritol and xylitol vs sorbitol, not pooled
Clinical Effects of Sugar Substitutes on Cariogenic Bacteria: A Systematic Review and Meta-Analysis. (2024)
Narrative (no effect size) Erythritol and xylitol significantly reduced the prevalence of salivary S. sobrinus1 studyUngraded
Grape seed extract (GSE) and its proanthocyanidin fractions vs Untreated or vehicle control (some studies vs positive antimicrobial controls, e.g. chlorhexidine/fluoride)
Antioxidant capacity · Streptococcus mutans (in vitro cultures and biofilms)
Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024)
GSE had the highest Trolox-equivalent antioxidant capacity (6.99 ug/mL) among the tested agents (Furiga).1 studyUngraded
Breastfeeding for <18 months vs Breastfeeding for ≥18 months
Dental caries (early childhood caries) · Preschool children (<6 years) · Cohort studies
Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024)
RR 0.41 [0.18, 0.92]5 studies · 2332 participantsUngraded
Disability (developmental, intellectual, or sensory) vs Persons without disabilities
Dental caries prevalence and severity · 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). High dental caries burden among PWDs: caries prevalence 60% to over 80% (abstract). Alkahtani 2019 (hearing-impaired adults, single-arm): caries prevalence 82.2%, treatment…NRUngraded
Antioxidant capsules 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)
Interventions for managing oral submucous fibrosis (2024) · Cochrane
Sudarshan 2012 reported a reduction in burning sensation but no baseline data, so change could not be determined.1 study · 20 participantsUngraded
Facemask vs Untreated control (no treatment)
Self-esteem (Piers-Harris self-concept scale) · 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 1.50 [-0.96, 3.96]1 study · 69 participantsUngraded
Opal Seal fluoride-releasing primer vs Conventional Transbond XT primer
Bracket failure · Patients undergoing fixed orthodontic treatment · During orthodontic treatment
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
No significant differences were observed in bracket failure rates among different primers, dental arches, bracket types, or sexes.1 study · 56 participantsUngraded
Silver diamine fluoride (SDF) vs Fluoride varnish
Primary caries prevention · Children and adults (with or without carious lesions) · 36 months, Permanent dentition (root)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
MD -0.20 [-0.91, 0.51]1 study · 100 participantsVery low
Prenatal vitamin D deficiency (maternal 25(OH)D measured at gestational weeks 24 to 38) vs Adequate prenatal vitamin D (sufficient maternal 25(OH)D)
Dental caries in children · Infants and children (aged about 2 to 8 years) whose mothers' vitamin D status was assessed during pregnancy · Maternal 25(OH)D measured at gestational weeks 24 to 38, Gestational-age subgroup: weeks 24 to 38
Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024)
OR 1.30 [1.15, 1.45]4 studiesUngraded
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 design: case-control
RETRACTED: Investigating the association between Candida albicans and early childhood dental caries: A… (2024)
OR 5.30 [1.72, 16.31]2 studies · 708 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, Mature teeth
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
OR 2.63 [1.14, 6.03]NRUngraded
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Mixed-type caries (crown and root) · Adults · Mixed-type caries
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 3.40 [3.10, 3.73]1 studyUngraded
Reverse Twin Block with lip pads and rapid maxillary expander (RME) vs Untreated control (no treatment)
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 5.27 [4.04, 6.50]1 study · 26 participantsUngraded
Lycopene plus intralesional betamethasone vs Placebo
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
Kumar 2007 (3-arm: lycopene vs lycopene+intralesional betamethasone vs placebo): appeared to show increased interincisal distance in the two active groups, but limited withdrawal information/incomplete data meant…1 studyUngraded
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 individual (patient) level · Children and adults with active dental caries (aged 1-50; mostly preschool/school children with primary dentition) · 3 weeks 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 0.39 [0.26, 0.60]2 studies · 384 participantsUngraded
Silver diamine fluoride (SDF) vs Placebo or no treatment
Caries arrest · Children and adults (with or without carious lesions) · 24 to 36 months, Primary dentition
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
MD 0.86 [0.39, 1.33]2 studies · 841 participantsLow
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
Postoperative discomfort or pain · 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
The trials did not measure postoperative discomfort or pain.0 studiesNo studies
Intervention NR
Serum vitamin D (25(OH)D): ECC vs caries-free · Region: North America (Fig 4)
The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024)
Mean difference -13.10 [-16.97, -9.23]4 studiesUngraded
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) · GNI >$40000
A systematic review and meta-analysis on early-childhood-caries global data. (2024)
Prevalence 47 [32, 62]14 studiesUngraded
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
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 3.11 [0.46, 5.77]2 studies · 520 participantsLow
AA+AG genotypes vs GG genotype
Dental caries · Children (<18 years) with vs without dental caries · Dominant model (AA+AG vs GG)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.07 [0.59, 1.96]3 studies · 855 participantsUngraded
Levamisole vs Antioxidant (Antoxid)
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 -7.00 [-13.56, -0.44]1 study · 30 participantsVery low
Extraction of the mandibular permanent first molar vs None (single-group prevalence)
Rotation of the mandibular second premolar · 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)
Prevalence 60.0 [10.7, 95.0]2 studies · 105 participantsUngraded
Cesarean section delivery vs Vaginal delivery
Early childhood caries (ECC) · Children aged <6 years · Time period: 2017 and before
RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024)
OR 1.10 [0.80, 1.52]11 studiesUngraded
Pentoxifylline vs Placebo or no active treatment
Difficulty in swallowing (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 0.42 [0.19, 0.92]1 study · 106 participantsUngraded
Silver diamine fluoride (SDF) vs Placebo or no treatment
Primary caries prevention · Children and adults (with or without carious lesions) · 36 months, Primary dentition
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
MD -1.14 [-1.58, -0.70]1 study · 373 participantsVery low
Intervention NR
Overall success (composite of clinical and radiographic success) · Full pulpotomy, mature teeth
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
Proportion 0.846 [0.739, 0.930]9 studiesUngraded
Silver diamine fluoride (SDF) vs Fluoride varnish
Secondary prevention of caries · Children and adults (with or without carious lesions) · Permanent dentition (root)
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
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
Adverse events for mother or child · 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
One trial (Harrison 2012) reported observing no adverse events; other trials provided no information on adverse events.1 studyUngraded
Orthodontic adhesive/composite containing nano-calcium fluoride (n-CaF2), alone or with DMAHDM vs Conventional/control orthodontic adhesive (e.g., Transbond XT) or negative control
Enamel remineralization extent · Human enamel specimens around orthodontic brackets (in vitro) · pH cycling 30 days, Overall
Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024)
A study using an orthodontic adhesive containing nano-calcium fluoride showed statistically significant remineralization compared with control orthodontic adhesives [35].1 studyUngraded
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight)
Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years)
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.44 [1.16, 1.78]16 studiesUngraded
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) · Continuous BMI, direct pooling (studies reporting BMI as a continuous variable)
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.01 [0.99, 1.03]4 studiesUngraded
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight)
Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Study design: case-control
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.31 [0.77, 2.22]4 studiesUngraded
Superelastic NiTi arch wire vs Multistrand stainless steel arch wire
Time to next/working arch wire · 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
No studies reported time to next/working arch wire0 studiesNo studies
Er:YAG laser irradiation of sound enamel before acid challenge vs No anticaries intervention (untreated enamel)
Enamel surface microhardness · Human tooth enamel specimens, sound/intact (in vitro) · After cariogenic acid challenge / pH cycling, sound enamel
Effect of Er:YAG Laser Irradiation on Preventing Enamel Caries: A Systematic Review and Meta-Analysis. (2024)
SMD 2.41 [0.70, 4.12]3 studiesUngraded
CC+CA genotypes vs AA genotype
Dental caries · Children (<18 years) with vs without dental caries · Dominant model (CC+CA vs AA)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 0.91 [0.55, 1.50]3 studies · 1327 participantsUngraded
Brushed less than twice per day vs Brushed twice or more per day
Fluorosis (percentage prevalence in permanent teeth) · Children exposed to topical fluoride when under 6 years old; fluorosis assessed in permanent teeth at 6 to 18 years · Fluorosis assessed when most permanent teeth of interest had erupted (6 to 18 years)
Topical fluoride as a cause of dental fluorosis in children (2024) · Cochrane
OR 0.88 [0.71, 1.08]3 studies · 2037 participantsVery low