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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 |
|---|---|---|---|
Silver diamine fluoride (SDF) plus fluoride varnish vs Sealants plus fluoride varnish (with or without restorations) Adverse effects · Children and adults (with or without carious lesions) · Study period (24 months), Children Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | Ruff 2022 reported that there were no adverse events during the study period; adverse events were not defined by the study authors. Assumed data available for 1398 participants. | 1 study · 1398 participants | Very low |
Male sex vs Female sex 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 1.38 [0.37, 5.14] | 2 studies | Ungraded |
Teledentistry (index test): dental caries diagnosis from photographs taken with DSLR or smartphone cameras; store-and-forward vs Visual/clinical dental examination (reference standard) Specificity · Children and adults with primary or permanent dentition undergoing dental caries assessment · Cross-sectional diagnostic accuracy (index test vs reference standard, in-vivo), Overall (studies reporting specificity; narrative synthesis) Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024) | Specificity ranged from 83% to 100% across studies (reported in 13 of 19 studies). No pooled estimate; meta-analysis not performed. | 13 studies | 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 plaque (sub- and supragingival calculus) · 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 0.92 [0.62, 1.37] | 1 study · 133 participants | 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: North America A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 3.89 [1.62, 6.16] | 7 studies | Ungraded |
Silver diamine fluoride (SDF) vs Placebo or no treatment Primary caries prevention · Children and adults (with or without carious lesions) · 24 to 36 months, Permanent dentition (root) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | MD -0.79 [-1.40, -0.17] | 3 studies · 439 participants | Moderate |
Cdx-2(rs11568820) A allele / genotype vs G allele / reference genotype Dental caries · Children (<18 years) with vs without dental caries · Not meta-analyzed (single study) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | Cdx-2(rs11568820) was reported by only one study (Qin 2019; 303 caries, 245 caries-free) and was therefore not subjected to meta-analysis (Results 'Meta-analysis'; Table 6). | 1 study · 548 participants | Ungraded |
Fluoride toothpaste less than 1000 ppm (lower concentration) vs Fluoride toothpaste 1000 ppm or more (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 | OR 0.79 [0.62, 1.02] | 3 studies · 2037 participants | Very low |
T allele vs C allele Dental caries · Children (<18 years) with vs without dental caries · Allelic model (T vs C) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.01 [0.83, 1.21] | 6 studies · 1986 participants | Ungraded |
Intervention NR Dental caries in children · Children's age subgroup: 2 to 4 years Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024) | OR 1.20 [1.04, 1.36] | 4 studies | Ungraded |
Silver diamine fluoride (SDF) vs Restoration (restorative treatment) Caries arrest · Children and adults (with or without carious lesions) · 12 months, Primary dentition (coronal) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | OR 0.03 [0.01, 0.10] | 1 study · 98 participants | Very low |
Overweight vs Normal weight (eutrophic) Dental caries experience (dmft), continuous · 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) | MD 0.31 [-0.10, 0.73] | 2 studies · 734 participants | Very low |
Occlusal splint vs Pharmacological therapy Muscle pain at rest · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 6 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Silver diamine fluoride (SDF) vs Placebo, control, and/or other interventions Caries arrestment at the individual level · Children and adults without systemic diseases affecting dental health · 3 weeks to 12 months The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024) | OR 3.86 [0.34, 43.96] | 5 studies · 720 participants | 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, Study region: Asia Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.71 [1.40, 2.10] | 5 studies | Ungraded |
TT+TG genotypes vs GG genotype Dental caries · Children (<18 years) with vs without dental caries · Dominant model (TT+TG vs GG) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.09 [0.76, 1.58] | 3 studies · 796 participants | Ungraded |
T allele vs C allele Dental caries · Children (<18 years) with vs without dental caries · Allelic model (T vs C), Asian ethnicity Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.98 [0.65, 1.50] | NR | Ungraded |
Intervention NR Change in Lactobacillus spp. in dental plaque · Single study (Ly et al. 2008), xylitol or maltitol, not pooled Clinical Effects of Sugar Substitutes on Cariogenic Bacteria: A Systematic Review and Meta-Analysis. (2024) | Narrative (no effect size) No significant change in Lactobacillus spp. after xylitol or maltitol consumption | 1 study | Ungraded |
Silver diamine fluoride (SDF) vs Glass ionomer cement (GIC) plus fluoride varnish Adverse effects · Children and adults (with or without carious lesions) · 6 months Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | Parents were asked if any harm was noticed due to the use of SDF, but the results were not reported in the study report; we could not determine whether there were any associated harms with either treatment (Mendiratta… | 1 study | Ungraded |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Severity of joint noise · People with temporomandibular disorders (TMD) · Long term (4 months), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -0.58 [-7.09, 5.93] | 1 study · 20 participants | Very low |
Facemask with rapid maxillary expansion (RME) vs Pushing Splints ANB (ANPog) · 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 1.40 [0.29, 2.51] | 1 study · 42 participants | Ungraded |
ACP light-cure adhesive vs Control Transbond XT adhesive Enamel demineralization score · Patients undergoing fixed orthodontic treatment · 6 months after bonding Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | At T2, the control group had an average score of 4.32 (±2.32), while the ACP group continued to exhibit a lower average score of 3.41 (±1.11) (p-value of 0.000). | 1 study · 26 participants | Ungraded |
Periodontitis vs No periodontitis High salivary P. gingivalis (over 10^4 CFU/ml) · Adults · Overall Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 3.38 [1.46, 7.83] | 2 studies | Ungraded |
Silver diamine fluoride (SDF) vs Atraumatic restorative treatment (ART) with glass ionomer cement (GIC) or glass ionomer material Primary caries prevention · Children and adults (with or without carious lesions) · Primary and permanent dentition Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | No studies reported this outcome | 0 studies | No studies |
Second molar at Demirjian stage E at extraction vs Second molar at Demirjian stage F-H at extraction Spontaneous space closure · Children and adolescents after extraction of a maxillary permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Maxilla Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 4.78 [1.56, 14.66] | 3 studies · 252 participants | Low |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Depression · People with temporomandibular disorders (TMD) · Short term, Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -2.58 [-4.62, -0.54] | 1 study · 32 participants | Ungraded |
Er:YAG laser irradiation vs Untreated / high-speed-handpiece control enamel Enamel resistance to demineralization (microhardness / lesion depth) · Human enamel adjacent to restorations or in pits and fissures (in situ / ex vivo) Clinical and ex-vivo effect of LASERs on prevention of early-enamel caries: systematic review & meta-analyses. (2024) | Narrative only (not meta-analyzed). Colucci: Er:YAG laser feasible for controlling caries progression adjacent to restorations but not able to prevent caries formation (optimum 2 Hz). Correa-Afonso: Er:YAG did not… | 2 studies | Ungraded |
Oral health education/promotion (oral hygiene advice plus diet and feeding practice advice) combined with clinical treatment for mother's dentition (basic restorative and preventive; 1 trial included CHX varnish application) vs Standard care 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 18 months Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | The mean dmft index score was 0.52 (standard care) versus 0 (advice + treatment group); relative effect not estimable; 50 participants (1 study); very low-certainty evidence. | 1 study · 50 participants | Very low |
Silver diamine fluoride (SDF) vs Silver nitrate plus fluoride varnish Adverse effects · Children and adults (with or without carious lesions) · 18 months, Children Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | Gao 2019 noted that "arrested lesions were stained black" (reported with no associated data). No other adverse effects observed, and no reports from parents of systemic disease. | 1 study · 1070 participants | Very low |
Facemask with rapid maxillary expansion (RME) vs Facemask with alternating rapid maxillary expansion and constriction (Alt-RAMEC) 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 -0.38 [-1.37, 0.60] | 3 studies · 97 participants | Ungraded |
Prenatal vitamin D deficiency (PVDD) vs Normal or sufficient prenatal vitamin D level Dental caries prevalence · Children aged 2 to 8 years · Maternal pregnancy to child age 2 to 8 years, Children of mothers with sufficient prenatal vitamin D Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024) | Proportion 0.25 | NR | 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 $10000-$19999 A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 4.04 [2.39, 5.68] | 9 studies | Ungraded |
Oral cancer patients (cases) vs Healthy controls DMFT index in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, DMFT (decayed, missing, filled teeth) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 0.65 [0.12, 1.18] | 2 studies | Ungraded |
Jaw opening exercises alone vs Ultrasound plus jaw opening exercises 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 -3.70 [-11.53, 4.13] | 1 study · 20 participants | Very low |
Mandibular headgear vs Chin cup 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 | Arun 1994 (n=60): ANB data not usable (no SDs; Mann-Whitney); no statistically significant difference between interventions (P>0.05). | 1 study · 60 participants | Ungraded |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Participant satisfaction or quality of life · People with temporomandibular disorders (TMD) · Short term (1 month), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -7.56 [-14.50, -0.63] | 2 studies · 75 participants | Ungraded |
Occlusal splint vs Acupuncture Participant satisfaction or quality of life · People with temporomandibular disorders (TMD) · Short term (1 month), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD 0.80 [-7.36, 8.96] | 1 study · 30 participants | Ungraded |
Intervention NR Overall success (composite of clinical and radiographic success) · Mature teeth, partial pulpotomy, irreversible pulpitis Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.808 [0.723, 0.881] | 5 studies | Ungraded |
Cranberry extract / juice and proanthocyanidin (flavonoid) 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) | Cranberry treatment disrupted biofilm integrity with agglutination/cell degradation at higher concentrations (Singhal), reduced polymicrobial biomass 38% at 96 h (Philip 2019), produced defective accumulation and… | 4 studies | Ungraded |
Intervention NR Spontaneous space closure · Maxilla: M2 Demirjian A-D vs G-H Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR >100.00 | 1 study | Ungraded |
T allele vs C allele Dental caries · Children (<18 years) with vs without dental caries · Allelic model (T vs C), Mixed dentition Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.80 [0.55, 1.15] | NR | 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) · Life expectancy: 71-75 years A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 5.18 | NR | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Change in probing depth (PD/PPD) · Adults (> 18 years) with peri-implant mucositis, receiving active treatment · 3 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD -0.10 [-0.57, 0.37] | 1 study · 38 participants | Ungraded |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Muscle pain when chewing · People with temporomandibular disorders (TMD) · Short term (mean 3 months), Myofascial pain TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 0.17 [0.02, 1.26] | 1 study · 40 participants | Very low |
Cesarean section delivery vs Vaginal delivery Early childhood caries (ECC) · Children aged <6 years · Study location: Europe RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024) | OR 1.48 [0.83, 2.63] | 5 studies | Ungraded |
Surgical miniplates with facemask vs Surgical miniplates with Class III elastics 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 -0.05 [-1.24, 1.14] | 1 study · 20 participants | 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) · Gini index: no inequality A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 62 | NR | 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) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -30.92 [-31.57, -30.27] | 1 study · 400 participants | Moderate |
NiTi arch wire of one cross-sectional size vs NiTi arch wire of a different cross-sectional size 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 wire | 0 studies | No studies |
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) · 6-year follow-up Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD -0.30 [-4.17, 3.57] | 1 study · 65 participants | Ungraded |