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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.

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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
High-frequency sugar consumption (three or more times daily) vs Low sugar intake (fewer than three times daily)
Dental caries experience in permanent dentition · Nigerian individuals with permanent dentition (approximately 12 years and older) · Community and school-based observational studies in Nigeria (12 of 14 in Southwest Nigeria), Permanent dentition
A systematic review and meta-analysis of the association between sugar intake and dental caries in Nigeria. (2024)
OR 1.15 [0.88, 1.52]4 studiesUngraded
Prenatal vitamin D deficiency (low maternal 25(OH)D during pregnancy) 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 · Prenatal exposure; dental caries assessed in children aged 2 to 8 years, Observational pregnancy/birth-cohort studies (one cross-sectional), mostly in developed countries (USA, Canada, Japan, Australia, Spain, Netherlands, Poland, New Zealand, Turkey), Overall (all studies pooled)
Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024)
OR 1.35 [1.22, 1.47]12 studies · 11021 participantsUngraded
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight)
Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Dental examinations of children; 15 countries across Europe, Asia, the Americas and Oceania, Adjustment for sex: no
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.74 [1.13, 2.68]6 studiesUngraded
Mineral trioxide aggregate (MTA) vs Calcium hydroxide (CH)
Overall success (composite of clinical and radiographic success) · Permanent teeth with carious pulp exposure · >=12 months, Irreversible pulpitis
Asked by 2 reviewsEfficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
OR 3.17 [1.25, 7.99]NRUngraded
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence)
Proportion of teeth with non-carious cervical lesions (NCCLs) in ancient skulls · Ancient/prehistoric human skulls (excavated/archaeological skeletal remains) · Archaeological/museum skeletal (skull) collections; multiple countries and pre-industrial historical periods, Overall (all included studies)
Investigation of the presence of Non-carious cervical lesions (NCCLs) in ancient adult skulls: analyzing… (2024)
Proportion 0.004 [0.001, 0.006]4 studies · 11578 participantsUngraded
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Dental caries (prevalence) · Adults · Population-based and clinical dental study samples; multiple countries (1994-2022), Crude OR
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 1.69 [1.41, 2.01]8 studiesUngraded
Overweight vs Normal weight (eutrophic)
Dental caries prevalence (any DMFT), dichotomous · Brazilian children/adolescents in permanent dentition (BMI classified by CDC 2000 growth charts) · Brazil
Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024)
OR 1.01 [0.43, 2.35]2 studies · 706 participantsVery low
Sociodemographic and behavioural factors (older age, lower education, lower income, poor oral hygiene/brushing, smoking, disadvantaged/slum residence, sex) vs Referent groups (younger, higher education/income, better oral hygiene, non-slum residence)
Factors associated with oral diseases · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Urban slums and non-slum/general-urban settings, LMICs
Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024)
Fourteen studies reported determinants: older age, less education, lower income, poor oral hygiene behaviour (brushing frequency, technique), infrequent dental visits and disadvantaged/slum residential setting were…14 studiesUngraded
Started toothbrushing with fluoride toothpaste at or 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 1.12 [0.89, 1.42]5 studies · 3592 participantsVery low
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 · 3 months (change from baseline)
Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane
MD 2.19 [1.00, 3.38]11 studies · 282 participantsUngraded
Occlusal splint vs Acupuncture
Muscle pain at rest · 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
Teledentistry diagnosis using DSLR or smartphone extra-oral photographs vs Visual or clinical examination
Intra-examiner reliability · Children and adults with primary or permanent dentition · Schools, juvenile detention facility, dental clinics, and hospitals, Overall
Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024)
no estimate extracted6 studiesUngraded
Tandem traction bow appliance vs Untreated control (no treatment)
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 3.30 [2.46, 4.14]1 study · 30 participantsUngraded
Grape seed extract or grape seed flavonoid fractions vs No extract or vehicle control; other antimicrobial agents
Cell damage or cytotoxicity · Streptococcus mutans cultures and biofilms · In vitro laboratory studies
Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024)
no estimate extracted1 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, Children aged ≤6 years; multiple countries (Asia, Europe, Americas); dental/clinical and community settings, Sample size: <100 (Table 6; abstract text erroneously states '<1000')
RETRACTED: Investigating the association between Candida albicans and early childhood dental caries: A… (2024)
OR 4.35 [2.75, 6.89]16 studiesUngraded
Teledentistry (index test): dental caries diagnosis from photographs taken with DSLR or smartphone cameras; store-and-forward vs Visual/clinical dental examination (reference standard)
Inter-examiner reliability · Children and adults with primary or permanent dentition undergoing dental caries assessment · Cross-sectional diagnostic accuracy (index test vs reference standard, in-vivo), In-vivo: dental clinics/hospitals, schools, and a juvenile detention facility (11 countries), Overall (studies reporting inter-examiner reliability; narrative synthesis)
Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024)
Inter-examiner reliability (kappa) reported in 13 studies, ranging from 0.44 to 0.91. No pooled estimate.13 studiesUngraded
Xylitol (low-intensity sweetener/sugar alcohol) in food products (chewing gum, milk, candy, or tablets) vs Sorbitol (low-intensity sweetener)
Change in Mutans streptococci (MS) count in dental plaque · Generally healthy individuals across all age groups (infants to elderly) · Post-consumption endpoint (varied durations across trials), All age groups, generally healthy; multiple countries; sugar substitutes delivered as chewing gum, milk, candy, or tablets, Xylitol vs sorbitol (4 studies)
Clinical Effects of Sugar Substitutes on Cariogenic Bacteria: A Systematic Review and Meta-Analysis. (2024)
SMD -0.45 [-0.69, -0.21]4 studies · 323 participantsUngraded
Mineral trioxide aggregate (MTA) vs Biodentine
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 0.89 [0.47, 1.69]6 studies · 348 participantsLow
Indirect bonding with flowable adhesive (Opal Bond MV) vs Direct bonding with Transbond XT
White spot lesion formation measured by QLF · Patients undergoing fixed orthodontic treatment · Before and after treatment, Fixed orthodontic treatment
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
The DB group exhibited significantly higher loss of fluorescence and degree of demineralization compared to the IB group between T0 and T1, with notable differences in specific quadrants (p <0.05 for ΔF and ΔF max).1 study · 51 participantsUngraded
TT+GG (homozygous) genotypes vs TG (heterozygous) genotype
Dental caries · Children (<18 years) with vs without dental caries · Over-dominant model (TT+GG vs TG), Children under 18 years; case-control and cross-sectional studies (China, Czech Republic, Turkey, Brazil, India)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 0.89 [0.66, 1.20]3 studies · 796 participantsUngraded
Cranberry extract / juice and proanthocyanidin (flavonoid) 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) · in vitro (laboratory)
Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024)
Cranberry non-dialyzable fractions showed antioxidant activity; the acetone-eluted NDMac fraction was ~twice as rich in polyphenols and had ~twice the antioxidant activity of the ethanol-eluted fraction (Neto 2017).1 studyUngraded
Facemask with rapid maxillary expansion (RME) vs Reverse Forsus
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 1.59 [0.80, 2.38]1 study · 30 participantsUngraded
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
Pain at 72 hours · Adults with symptomatic apical periodontitis (no signs of spreading infection or systemic involvement) · 72 hours
Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane
The median pain at 72 hours in the control group was 0 (range 0 to 10); the median pain at 72 hours in the intervention group was the same (median 0, range 0 to 7). P = 0.116 (Mann-Whitney U).1 study · 72 participantsLow
Silver diamine fluoride (SDF; 38% in most trials, 30% in three) vs Other methods (pooled: nano-silver fluoride, sodium fluoride varnish)
Caries arrestment at the surface level · Children and adults with active dental caries (aged 1-50; mostly preschool/school children with primary dentition) · 12 to 18 months, Children/adults with dental caries; multiple countries; community/clinic care setting not clearly specified, Overall (all comparators pooled)
The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024)
OR 1.03 [0.47, 2.27]3 studies · 5394 participantsModerate
Primary teeth / primary dentition (younger children) vs Permanent teeth / permanent dentition (older children)
Dental caries risk · Institutionalized orphan children · Orphanages/childcare institutions in low- and middle-income countries (India, Iran, China, Yemen, Egypt, Lithuania, Malaysia), Overall (pooled)
Caries in orphan children: prevalence and determinants-a systematic review and meta-analysis. (2024)
RR 1.31 [0.91, 1.89]5 studies · 1892 participantsVery low
Prophylaxis (teeth cleaning) and CHX or iodine-NaF solution application in the dentition of women (mothers) vs Placebo
dmfs index score · 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
dmfs was listed in the SoF table but not assessed (no trial reported it).0 studiesNo studies
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint)
Range of mandibular motion · People with temporomandibular disorders (TMD) · Short term, Disc displacement (with/without reduction)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
MD -2.41 [-7.78, 2.96]1 study · 30 participantsUngraded
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, Unspecified/mixed diagnosis
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
Proportion 0.909 [0.833, 0.965]NRUngraded
Silver diamine fluoride (SDF) vs Fluoride varnish
Caries arrest · 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
Systemic antibiotics without surgical intervention (with or without analgesics) vs Matched placebo without surgical intervention (with or without analgesics)
Outcome NR · Adults with symptomatic apical periodontitis or acute apical abscess
Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane
We found no studies comparing systemic antibiotics versus a matched placebo provided without a surgical intervention.0 studiesNo studies
Overweight/obesity (combined) vs Normal weight (eutrophic)
Dental caries prevalence (any dmft), dichotomous · Brazilian children under 5 years in primary dentition (BMI classified by WHO 2006 Z-score) · Brazil
Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024)
OR 0.86 [0.60, 1.22]3 studiesVery low
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) · Less than 3 months
Interventions for managing oral submucous fibrosis (2024) · Cochrane
MD -0.06 [-10.64, 10.52]2 studies · 58 participantsVery low
Cesarean section delivery vs Vaginal delivery
Early childhood caries (ECC) · Children aged <6 years · Community/population-based; multiple countries, Time period: After 2018
RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024)
OR 1.01 [0.75, 1.35]13 studiesUngraded
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Dental caries (prevalence) · Adults · Population-based and clinical dental study samples; multiple countries (1994-2022), Female
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 1.36 [0.74, 2.49]2 studiesUngraded
Genome-wide common variants (aggregate additive; LD score regression) vs Not applicable (variance-component estimate)
Dental caries - SNP-based heritability · Japanese adults (present-study cohort) · Lifelong (germline genotype), Population-based genetic association study (Japanese direct-to-consumer genetic testing cohort), LDSC heritability (present study)
Genome-wide association meta-analysis identifies two novel loci associated with dental caries. (2024)
h2 (observed-scale SNP heritability) 0.02581 study · 45525 participantsUngraded
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, Partial pulpotomy
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
Proportion 0.882NRUngraded
Intervention NR
Overall success (composite of clinical and radiographic success) · Full pulpotomy, unspecified/mixed diagnosis
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
Proportion 0.903 [0.801, 0.973]5 studiesUngraded
Prenatal vitamin D deficiency (PVDD) 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, Mostly developed countries (Europe and America), Meta-regression adjusted for gestational age, child age, and maternal vitamin D level
Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024)
OR 1.28 [1.23, 1.33]NRUngraded
Silver diamine fluoride (SDF) vs Placebo, control, and/or other interventions
Caries arrestment at the tooth level · Children and adults without systemic diseases affecting dental health · 6 months to 12 months
The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024)
OR 1.74 [0.88, 3.46]5 studies · 743 participantsModerate
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
Improvement in range of jaw movement · 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 range of jaw movement.0 studiesNo studies
CC genotype vs CT+TT genotypes
Dental caries · Children (<18 years) with vs without dental caries · Recessive model (CC vs CT+TT), Children under 18 years; case-control and cross-sectional studies (China, Czech Republic, Turkey, Brazil, India)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.23 [0.97, 1.55]3 studies · 1329 participantsUngraded
Superelastic NiTi arch wire vs Multistrand stainless steel arch wire
Time to alignment · 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
Cobb 1998 measured time to alignment but reported results only as graphs, with no numerical data1 studyUngraded
Obesity vs Normal weight (eutrophic)
Dental caries prevalence (any dmft), dichotomous · Brazilian children in primary dentition (BMI classified by CDC 2000 growth charts) · Brazil
Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024)
OR 0.44 [0.08, 2.61]2 studies · 709 participantsVery low
Silver diamine fluoride (SDF) vs Fluoride varnish
Caries arrest · Children and adults (with or without carious lesions) · Permanent dentition (coronal)
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
Facemask with rapid maxillary expansion (RME) vs Facemask only
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 -0.15 [-0.94, 0.64]2 studies · 60 participantsLow
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) · Less than 3 months
Interventions for managing oral submucous fibrosis (2024) · Cochrane
MD -52.00 [-62.04, -41.96]1 study · 25 participantsVery low
Facemask with rapid maxillary expansion (RME) vs Modified tandem appliance
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 2.28 [1.35, 3.21]1 study · 32 participantsUngraded
Silver diamine fluoride (SDF) vs Silver nitrate plus fluoride varnish
Caries arrest · Children and adults (with or without carious lesions) · 18 months, Primary dentition (coronal)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
MD -0.10 [-0.51, 0.31]1 study · 1070 participantsLow
NiTi arch wire of one cross-sectional size vs NiTi arch wire of a different cross-sectional size
Time to alignment · 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
Time to alignment: not reported0 studiesNo studies
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy)
Frequency of joint noise · People with temporomandibular disorders (TMD) · Short term (3 months), Myofascial pain TMD
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
RR 1.50 [0.32, 6.94]1 study · 18 participantsVery low