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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.
10,375 questions in 429 reviews · Oral Health
current versionsNo 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.
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
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), 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), 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) 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, 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) 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 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) · 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) · 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 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, 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) 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, 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) · 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 · 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) 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), 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), 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 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 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, 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) · 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 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 |
Experimental adhesive containing ammonium-based methacrylate monomer (MADQUAT) vs Conventional/control orthodontic adhesive (e.g., Transbond XT) or negative control Enamel remineralization / carious lesion development · Human enamel specimens around orthodontic brackets (in vitro) · biofilm cariogenic challenge 5 days, Overall Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024) | A study using an orthodontic adhesive containing ammonium-based methacrylate showed significant remineralization power compared with control adhesives [37]. | 1 study | Ungraded |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Dental caries (prevalence) · Adults · Overall Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.57 [1.20, 2.07] | 10 studies | Ungraded |
Breastfeeding for <6 months vs Breastfeeding for ≥6 months Dental caries (early childhood caries) · Preschool children (<6 years) · Case-control studies Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | OR 0.53 [0.41, 0.67] | 2 studies · 1201 participants | Ungraded |
Superelastic NiTi arch wire vs Thermoelastic NiTi arch wire Pain day 1 · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 7 days Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | MD 6.96 [1.82, 12.10] | 3 studies · 94 participants | Moderate |
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight) Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Region: American countries Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024) | OR 1.28 [0.91, 1.81] | 7 studies | Ungraded |
SDF (given at a particular frequency, concentration, or duration) vs SDF (given at a different frequency, concentration, or duration) Secondary prevention of caries · Children and adults (with or without carious lesions) · 30 months, Primary dentition Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | MD -0.10 [-0.61, 0.41] | 1 study · 203 participants | Very low |
Overweight/obesity (combined) vs Normal weight (eutrophic) Dental caries prevalence (any dmft), dichotomous · Brazilian children in primary dentition (BMI classified by CDC 2000 growth charts) Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024) | OR 0.83 [0.45, 1.54] | 2 studies · 826 participants | Very low |
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) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -46.00 [-53.44, -38.56] | 1 study · 25 participants | Very low |