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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. Every word you type has to appear somewhere in the question, and the closest matches are ranked first.
75,239 questions in 5,342 reviews
current versionsNo 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.
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Consumption of xylitol chewing gum by women (mothers) vs Consumption of CHX/xylitol gum by women, or CHX varnish applied to women's dentition dmft index score · For interventions, pregnant women and mothers of infants in the first year of life; for outcomes, children up to 6… · Children assessed at 5 yrs Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | MD -2.39 [-4.10, -0.68] | 1 study · 113 participants | 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 clinical attachment level (CAL) · 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 0.44 [0.24, 0.64] | 13 studies · 414 participants | Very low |
Intervention NR Overall success (composite of clinical and radiographic success) · Mature teeth, full pulpotomy, irreversible pulpitis Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.817 [0.702, 0.909] | 8 studies | Ungraded |
Slum setting vs Non-slum urban setting Oral health practices · Adults in LMIC urban and slum settings · LMIC slum and non-slum urban settings Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | no estimate extracted | 11 studies | Ungraded |
Coated superelastic NiTi wire (BioCosmetic, Titanol, TP Aesthetic or Tooth Tone) vs A different coated superelastic NiTi wire Alignment rate · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 8 weeks Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Four-arm study of different coated superelastic NiTi wires (Ulhaq 2017); reduction in LII over 8 weeks; no difference between the four groups (ANOVA P=0.627) | 1 study | Ungraded |
Cesarean section delivery vs Vaginal delivery Early childhood caries (ECC) · Children aged <6 years · Community/population-based; multiple countries, Study design: Cohort RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024) | OR 1.15 [0.90, 1.46] | 9 studies | Ungraded |
Periodontal therapy (scaling and root planing), post-treatment vs Pre-treatment High-level S. mutans (over 10^4 CFU/ml) · Periodontitis patients · Post-treatment, Salivary/plaque microbiology samples from case-control studies, Overall Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.54 [0.47, 5.02] | 3 studies | Ungraded |
Fluoride toothpaste 440 ppm (lower concentration) vs Fluoride toothpaste 1450 ppm (higher concentration) 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 | RR 0.72 [0.58, 0.89] | 1 study · 1009 participants | Moderate |
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), Children under 18 years; case-control and cross-sectional studies (China, Czech Republic, Turkey, Brazil, India), 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] | NR | Ungraded |
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 outcome | 0 studies | No 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 participants | Very low |
TT genotype vs TC+CC genotypes Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TC+CC), Children under 18 years; case-control and cross-sectional studies (China, Czech Republic, Turkey, Brazil, India), 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] | NR | Ungraded |
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 participants | Very 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 studies | Ungraded |
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 participants | Ungraded |
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 participants | Ungraded |
Overweight/obesity (combined) vs Normal weight (eutrophic) Dental caries prevalence (any DMFT), dichotomous · Brazilian children/adolescents (BMI classified by WHO 2007 percentile) · Brazil 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 participants | Very 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, Children aged ≤6 years; multiple countries (Asia, Europe, Americas); dental/clinical and community settings, 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 studies | Ungraded |
TT genotype vs TC+CC genotypes Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TC+CC), 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 1.21 [0.93, 1.56] | 5 studies · 1586 participants | Ungraded |
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, Hearing-impairment and cerebral-palsy clinical settings in Saudi Arabia (Riyadh) 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… | NR | Ungraded |
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) · Dental examinations of children; 15 countries across Europe, Asia, the Americas and Oceania, 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 studies | Ungraded |
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 extracted | 1 study | Ungraded |
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 participants | Low |
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, 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 studies | Ungraded |
Adhesive flash-free ceramic brackets vs Adhesive precoated ceramic brackets Enamel demineralization (QLF ΔF) · Patients undergoing fixed orthodontic treatment · Baseline to debonding, Fixed orthodontic treatment 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 participants | Ungraded |
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 8.0 | 1 study | Ungraded |
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 0.902 | NR | Ungraded |
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, Healthy children and/or adolescents (<18 years) without systemic disease; RCTs from multiple countries (India, Thailand, Spain, Australia, New Zealand, Sweden, Poland, Colombia, Saudi Arabia); mostly school/community and clinic settings, 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 participants | Very 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 participants | 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) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD 8.61 [-4.52, 21.74] | 3 studies · 98 participants | Very 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 participants | Ungraded |
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), 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 1.33 [1.06, 1.67] | 6 studies · 1986 participants | Ungraded |
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 comparison | 0 studies | No 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, Children/adults with dental caries; multiple countries; community/clinic care setting not clearly specified, 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 participants | Ungraded |
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 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 studies | Ungraded |
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 participants | Ungraded |
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 · 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) | 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 sensitive | 13 studies | Ungraded |
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 study | Ungraded |
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), 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 1.04 [0.64, 1.70] | 3 studies · 855 participants | Ungraded |
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), University clinics and hospitals in 8 countries (children/adolescents <18 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 participants | Ungraded |
TT genotype vs TC+CC genotypes Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TC+CC), Children under 18 years; case-control and cross-sectional studies (China, Czech Republic, Turkey, Brazil, India), 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] | NR | Ungraded |
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 3.7 | 1 study | Ungraded |
Clearfil Protect Bond vs Transbond XT conventional adhesive White spot lesion rate and volume · Patients undergoing fixed orthodontic treatment · 8 weeks after bonding, Fixed orthodontic treatment 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 participants | Ungraded |
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 comparison | 0 studies | No 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, Fixed orthodontic treatment 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 participants | Ungraded |
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, Mostly developed countries (Europe and America), 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 studies | Ungraded |
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) · Europe, Region: Europe A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 2.26 [0.69, 3.82] | 11 studies | Ungraded |
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 studies | No 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 participants | Ungraded |
Slum setting vs Non-slum urban setting Self-perceived oral health · Adults in LMIC urban and slum settings · LMIC slum and non-slum urban settings Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | no estimate extracted | 6 studies | Ungraded |