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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. Words match anywhere in the field.
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 |
|---|---|---|---|
Antioxidants (lycopene, curcumin, Oxitard) 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 0.51 [0.21, 1.22] | 1 study · 120 participants | Ungraded |
Cleft lip and palate vs No cleft lip and palate Lactobacillus spp. mean levels/counts · Children and adolescents aged 0 to 18 years with nonsyndromic cleft lip and palate Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | MD 1.40 [1.33, 1.47] | 2 studies · 152 participants | Ungraded |
Overweight vs Normal weight (eutrophic) Dental caries experience (DMFT), continuous · Brazilian children/adolescents in permanent dentition (BMI classified by CDC 2000 growth charts) Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024) | MD -0.06 [-1.03, 0.91] | 2 studies · 446 participants | Very low |
TT+TC genotypes vs CC genotype Dental caries · Children (<18 years) with vs without dental caries · Dominant model (TT+TC vs CC), Real-time quantitative PCR genotyping Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.87 [0.47, 1.61] | NR | Ungraded |
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) · Region: Africa A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 42 [32, 53] | 3 studies | Ungraded |
Intervention NR Overall success (composite of clinical and radiographic success) · Full pulpotomy, irreversible pulpitis Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.837 [0.741, 0.916] | 12 studies | Ungraded |
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 | RR 0.83 [0.61, 1.13] | 1 study · 3939 participants | Very 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 dmft index score · 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 | dmft was listed in the SoF table but not assessed (not reported for this comparison). | 0 studies | No studies |
Oral cancer patients (cases) vs Healthy controls Mean number of missing teeth in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, Missing teeth (mean count) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 0.59 [-0.04, 1.22] | 3 studies | Ungraded |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · More than 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -27.60 [-36.21, -18.99] | 1 study · 90 participants | Moderate |
Intervention NR Decayed, missing, filled surfaces (DMFS) · Percentage of sites with CAL >=3 mm (tertiles); single study (Robert 2019); adjusted Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.03 [1.00, 1.05] | 1 study | Ungraded |
Intervention NR Serum vitamin D (25(OH)D): ECC vs caries-free · Cross-sectional studies (Fig 3) The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | Mean difference -6.10 [-8.02, -4.19] | 3 studies | Ungraded |
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, Region: Asia RETRACTED: Investigating the association between Candida albicans and early childhood dental caries: A… (2024) | OR 3.62 [2.53, 5.20] | 12 studies · 2347 participants | Ungraded |
Single-strand superelastic NiTi arch wire vs Coaxial superelastic NiTi arch wire Pain · 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 | Pain: not reported | 0 studies | No studies |
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control) Lactobacillus count (CFU/mL) · Children and/or adolescents (<18 years) without background systemic disease · follow-up: mean 5.2 months, Overall (all presentations pooled) Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024) | MD -0.78 [-1.65, 0.09] | 6 studies · 1143 participants | Very low |
Maternal smoking during pregnancy vs No maternal smoking during pregnancy Dental caries · Children · Study region: Australia Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.68 [1.35, 2.10] | 1 study | Ungraded |
Postoperative systemic antibiotics (phenoxymethylpenicillin/penicillin VK, 7-day course), partial or total chemo-mechanical debridement and analgesics vs Matched placebo, partial or total chemo-mechanical debridement and analgesics Swelling at 72 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 72 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | SMD 0.02 [-0.49, 0.52] | 2 studies · 61 participants | Very low |
Serum 25(OH)D 50–75 nmol/l vs Serum 25(OH)D ≥ 75 nmol/l Early childhood caries (ECC) · Preschool children ≤6 years The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | OR 1.42 [1.26, 1.60] | 6 studies · 5746 participants | Ungraded |
CO2 laser combined with fluoride vs Fluoride alone Enamel demineralization / mineral loss · Human enamel specimens under cariogenic challenge (in situ / ex vivo) Clinical and ex-vivo effect of LASERs on prevention of early-enamel caries: systematic review & meta-analyses. (2024) | Narrative only (secondary question: laser-fluoride synergy). Takate: combined low-power CO2 laser plus 1.23% APF gave greater inhibition of mineral loss than either alone (APF after laser gave maximum inhibition).… | 2 studies | Ungraded |
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) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD 8.83 [8.22, 9.45] | 3 studies · 620 participants | Moderate |
M2 Demirjian stages F-G vs M2 Demirjian stages E-D Spontaneous space closure · Children and adolescents with maxillary permanent first molar extraction · Follow-up to complete eruption of the permanent second molar, Maxilla Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR >100.00 [0.01, >100.00] | 3 studies | Ungraded |
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight) Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Sample size: >900 Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024) | OR 1.59 [1.25, 2.02] | 8 studies | Ungraded |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Joint pain at rest · People with temporomandibular disorders (TMD) · Short term (6 weeks), Disc displacement without reduction (DDwoR) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 0.85 [0.47, 1.57] | 1 study · 31 participants | Very low |
Remineralizing orthodontic adhesives vs Control orthodontic adhesives Ion release · Human teeth with early enamel lesions surrounding orthodontic brackets · 14 days to 6 months Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024) | no estimate extracted | 8 studies | Ungraded |
Second molar at Demirjian stage E-F at extraction vs Second molar at Demirjian stage G-H 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 4.44 [0.43, 46.10] | 3 studies | Ungraded |
Overweight/obesity (combined) vs Normal weight (eutrophic) Dental caries prevalence (any DMFT), dichotomous · Brazilian children/adolescents in permanent dentition (BMI classified by WHO 2006 Z-score) Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024) | Pooled effect not estimable (not shown in article); I2=85%; Very low | 2 studies | Very low |
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 dmft index score · 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 | MD -0.12 [-0.59, 0.36] | 2 studies · 652 participants | Low |
Mineral trioxide aggregate (MTA) vs Calcium hydroxide (CH) 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 2.41 [1.28, 4.51] | 7 studies · 377 participants | Low |
Facemask with rapid maxillary expansion (RME) vs Reverse Twin Block with lip pads and rapid maxillary expander (RME) 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 -1.04 [-2.07, -0.01] | 1 study · 26 participants | Ungraded |
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management) Frequency of joint noise · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 4 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Outcome NR · Adults (> 18 years) with peri-implantitis, receiving supportive treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Planned comparison; no studies met the inclusion criteria. The review found only one study of peri-implant disease (peri-implant mucositis, active treatment) and no studies including people with peri-implantitis… | NR | No studies |
Facemask (RME) or modified facemask vs Surgically-anchored appliance (miniscrews or miniplates) Perceived need for surgery in adulthood · 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 | SoF4: Perceived need for surgery in adulthood - Not measured. | 0 studies | No studies |
Second molar at Demirjian stage A-D at extraction vs Second molar at Demirjian stage F-H 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 3.11 [1.25, 7.72] | 3 studies · 95 participants | Low |
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) · Region: Asia-Oceania A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 52 [45, 60] | 33 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) · GNI $5000-$9999 A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 4.28 [2.58, 5.97] | 10 studies | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Pattern of dental service utilisation and barriers · Adult residents of slums and non-slum urban settings of LMICs Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Utilisation was generally low, episodic and mostly problem/pain-driven (pain-driven visits ~70-99%); widespread self-care/home remedies were used as alternatives to professional care; lack of funds/cost, income, age,… | NR | 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 · >=12 months, Hemostasis >=10 min Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.862 | NR | Ungraded |
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 Analgesic use · Adults with symptomatic apical periodontitis (no signs of spreading infection or systemic involvement) · 7 days Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | RR 0.87 [0.48, 1.55] | 1 study · 72 participants | 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 Child plaque (any plaque visible on any teeth) · 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 | RR 0.35 [0.26, 0.47] | 1 study · 441 participants | Ungraded |
Self-etch primer bonding system (3M Transbond Plus) vs Conventional three-step bonding system (3M Transbond XT) White spot lesion incidence · Patients undergoing fixed orthodontic treatment · 2 and 4 months after treatment start Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Group 2 (3M Transbond Plus) had a significantly higher incidence of WSLs than Group 1 (3M Transbond XT) (p <0.05). | 1 study · 75 participants | Ungraded |
Intralesional triamcinolone vs Intralesional triamcinolone plus salvianolic acid B Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · More than 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -2.38 [-5.64, 0.88] | 1 study · 28 participants | Very low |
Silver diamine fluoride (SDF) vs Glass ionomer cement (GIC) plus fluoride varnish 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 |
Vasodilators (isoxsuprine, xanthinol nicotinate) 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 2.51 [-0.99, 6.01] | 2 studies · 85 participants | Very low |
Silver diamine fluoride (SDF) vs Chlorhexidine 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 -0.40 [-0.95, 0.15] | 1 study · 99 participants | Very low |
Genome-wide common variants (aggregate additive; LD score regression) vs Not applicable (variance-component estimate) Periodontal disease - SNP-based heritability · Japanese adults (present-study cohort) · Lifelong (germline genotype), LDSC heritability (present study) Genome-wide association meta-analysis identifies two novel loci associated with dental caries. (2024) | h2 (observed-scale SNP heritability) 0.0519 | 1 study · 45525 participants | Ungraded |
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management) Recurrence rate · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 4 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Grape seed extract (GSE) and its proanthocyanidin fractions vs Untreated or vehicle control (some studies vs positive antimicrobial controls, e.g. chlorhexidine/fluoride) Biofilm morphological changes · Streptococcus mutans (in vitro cultures and biofilms) Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024) | GSE decreased microcolony number and biofilm thickness at 2000 ug/mL (Furiga) and significantly altered bacterial cell structure with 50 ug/2 mL GSE candy (Nowaczyk). | 2 studies | 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) · Non-linear dose-response (restricted cubic splines) Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024) | Fig. 5: significant non-linear (restricted cubic spline) dose-response between BMI and childhood dental caries; relative risk rises at higher BMI (curve reaches ~2.4-2.9 at BMI 30-35) and is also elevated among… | NR | Ungraded |
GG genotype vs GA+AA genotypes Dental caries · Children (<18 years) with vs without dental caries · Recessive model (GG vs GA+AA), Zhang 2006 removed, Sensitivity analysis (Zhang 2006 excluded) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.86 [0.48, 1.54] | 3 studies · 1329 participants | Ungraded |
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 gingival health (mild or moderate bone loss) · 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 | RR 1.43 [0.42, 4.85] | 1 study · 133 participants | Ungraded |