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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.
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 |
|---|---|---|---|
Light-cured resin-modified glass ionomer cement vs Resin adhesive (Transbond XT) First-time bracket failure · Patients undergoing fixed orthodontic treatment · Before and after treatment Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | No differences were observed in the proportions of patients experiencing first-time bracket failures when participants were bonded with either resin adhesive or RM-GIC (p > 0.05). | 1 study · 197 participants | Ungraded |
Silver diamine fluoride (SDF) vs Chlorhexidine varnish Caries arrest · 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 |
Extraction of a maxillary permanent first molar vs Extraction of a mandibular permanent first molar 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 Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 7.77 [4.99, 12.11] | 9 studies · 1349 participants | Low |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Change in gingival recession (REC) · Adults (> 18 years) with peri-implant mucositis, receiving active treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Only one study reported evidence for adjunctive aPDT in people with peri-implant disease (Al Rifaiy 2022). Data were only available for two outcomes (PPD and BOP), both reported only at three months. No studies… | NR | No studies |
Intralesional steroid injection plus adjunctive treatment vs Intralesional steroid injection alone 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 -0.85 [-3.31, 1.61] | 2 studies · 148 participants | Low |
Oral cancer patients (cases) vs Healthy controls Periodontal pocket depth (PPD) in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, PPD (periodontal pocket depth) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 1.64 [-0.20, 3.47] | 2 studies | Ungraded |
Intervention NR Overall success (composite of clinical and radiographic success) · Partial pulpotomy, immature teeth Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.924 [0.851, 0.976] | 3 studies | Ungraded |
Intervention NR Spontaneous space closure · Mandible: M2 Demirjian E-F vs G-H Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 42.0 | 1 study | Ungraded |
CC genotype vs CA+AA genotypes Dental caries · Children (<18 years) with vs without dental caries · Recessive model (CC vs CA+AA) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.87 [0.70, 1.09] | 3 studies · 1327 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: Africa A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 3.47 [1.37, 5.56] | 3 studies | Ungraded |
Slum setting vs Non-slum urban setting Determinants of oral diseases · 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 | 14 studies | Ungraded |
Chin cup (600 g force) vs Chin cup (300 g force) 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 -0.30 [-1.12, 0.52] | 1 study · 40 participants | Ungraded |
Occlusal splint vs Pharmacological therapy Self-reported joint pain when chewing · People with temporomandibular disorders (TMD) · Short term (3 months), Osteoarthritis Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 2.10 [0.83, 5.30] | 1 study · 29 participants | Very low |
Breastfeeding <24 months vs Breastfeeding ≥24 months Dental caries (ECC) · Preschool children under 6 years of age · First dental examination before age 6 years, Cohort studies; sensitivity analysis excluding Peres et al. (2017) Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | RR 0.49 [0.39, 0.62] | 3 studies | Ungraded |
Pentoxifylline vs Spirulina 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 0.50 [-6.60, 7.60] | 1 study · 40 participants | Very low |
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate) Incidence of new ICLs (proportion of tooth surfaces developing new lesions) · Patients undergoing fixed orthodontic treatment with fixed (multibracket) appliances, followed for development of new… · During fixed orthodontic treatment (development of new lesions), Overall (random-effects model) Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024) | Proportion 0.15 [0.08, 0.26] | 4 studies · 1890 participants | Very low |
Silver diamine fluoride (SDF) vs Sealants or resin infiltration Caries arrest · 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 data in either dentition type | 0 studies | No studies |
Breastfeeding vs No breastfeeding Dental caries (ECC) · Preschool children under 6 years of age · First dental examination before age 6 years, Cohort studies; sensitivity analysis excluding studies 37, 41, 45, 53, and 56 Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | RR 0.82 [0.71, 0.95] | 5 studies | Ungraded |
Salivary Actinobacillus level vs Not specified Salivary S. mutans level · Patients with aggressive periodontitis · Overall Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 0.08 [0.01, 0.85] | 1 study | Ungraded |
Hybrid Hyrax (RME) with miniscrews and Class III elastics vs Conventional Hyrax (RME) with miniscrews and Class III elastics 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 0.91 [-0.56, 2.38] | 1 study · 35 participants | Ungraded |
Slum residence vs Non-slum urban residence Dental caries (odds), slum vs non-slum residence · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Slum vs non-slum urban (Osuh 2022, Nigeria) Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | OR 1.21 [0.94, 1.56] | 1 study · 1357 participants | 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: Europe RETRACTED: Investigating the association between Candida albicans and early childhood dental caries: A… (2024) | OR 10.13 [6.01, 17.09] | 5 studies · 635 participants | Ungraded |
Adhesive precoated flash-free brackets vs Conventional ceramic brackets Enamel demineralization (DIAGNOdent score) · Patients undergoing fixed orthodontic treatment · Baseline, 1 month, and 6 months after bonding Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Intergroup evaluation showed that there were no statistically significant differences in demineralization measurements between all sides of the conventional and flash-free brackets at all the time intervals (p >0.05). | 1 study · 30 participants | Ungraded |
Intervention NR Overall success (composite of clinical and radiographic success) · Immature teeth, irreversible pulpitis Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.790 [0.667, 0.892] | 2 studies | Ungraded |
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 saliva · Generally healthy individuals across all age groups (infants to elderly) · Post-consumption endpoint (varied durations across trials), Xylitol gum vs sorbitol gum (2 studies) Clinical Effects of Sugar Substitutes on Cariogenic Bacteria: A Systematic Review and Meta-Analysis. (2024) | SMD -0.16 [-0.44, 0.12] | 2 studies · 201 participants | Ungraded |
Superelastic NiTi arch wire vs Conventional (stabilised) NiTi arch wire Root resorption · 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 | Root resorption: not reported | 0 studies | No studies |
T allele vs G allele Dental caries · Children (<18 years) with vs without dental caries · Allelic model (T vs G) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.00 [0.81, 1.23] | 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), Permanent dentition Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.90 [0.54, 1.49] | 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 >$40000 A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 3.34 [1.79, 4.88] | 13 studies | Ungraded |
Dental caries (DT not equal to 0) vs No dental caries Periodontitis (prevalence) · Adults · Crude OR Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 2.35 [2.04, 2.70] | 2 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Regular toothbrushing usage (prevalence) · Children (<18 years) with intellectual and developmental disabilities (IDD) in India · Overall Oral health status of children with intellectual and developmental disabilities in India: a systematic… (2024) | Prevalence 91 [80, 96] | 6 studies · 1036 participants | Ungraded |
Transbond XT with 1% chitosan and 1% TiO2 nanoparticles vs Transbond XT adhesive Streptococcus mutans count · 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) | Experimental group: significant decrease in S. mutans count was observed at the time points of 1 day, 2 months, and 6 months for both maxillary lateral incisor (p = 0.01) and maxillary second premolar teeth (p = 0.001). | 1 study · 24 participants | Ungraded |
Biodentine 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 6.03 [0.97, 37.6] | 2 studies | Ungraded |
Used fluoride mouth rinse vs No fluoride mouth rinse 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 1.44 [0.62, 3.38] | 1 study | Ungraded |
Facemask with rapid maxillary expansion (RME) vs Mini maxillary protractor 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 -0.06 [-1.52, 1.40] | 1 study · 32 participants | Ungraded |
Thermoelastic copper NiTi (CuNiTi) arch wire vs Conventional 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 |
Silver diamine fluoride (SDF) vs Atraumatic restorative treatment (ART) with glass ionomer cement (GIC) or glass ionomer material Adverse effects · Children and adults (with or without carious lesions) · 48 hours to 24 months, Children Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | In 1 study, 115 of 118 children had black stains on teeth treated with SDF; there were no other adverse effects or allergic reactions. In 1 study, the rate of adverse effects reported by caregiver and person who… | 3 studies · 482 participants | Very low |
High-dose vitamin D3 supplementation during pregnancy (2400 IU/day from pregnancy week 24 to 1 week postpartum, in addition to the recommended 400 IU/day) vs Low-dose (standard) vitamin D supplementation as recommended in national pregnancy guidelines Caries presence in primary teeth · For interventions, pregnant women, mothers or other caregivers of infants in the first year of life; for outcomes,… · Children assessed at 6 yrs Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | RR 0.99 [0.70, 1.41] | 1 study · 496 participants | Very 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 recurrent periodontitis, receiving supportive (maintenance) periodontal care · 6 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD 0.07 [-0.26, 0.40] | 2 studies · 85 participants | Very low |
Moderate-severe active dental caries (exposure) vs Caries-free or mild dental caries (control) Salivary IL-6 level (pg/mL) · Children and young adults (3-25 years) Activity and levels of TNF-α, IL-6 and IL-8 in saliva of children and young adults with dental caries: a… (2024) | SMD 11.60 [6.27, 16.94] | 11 studies · 879 participants | Ungraded |
Er:YAG laser irradiation of sound enamel before acid challenge vs No anticaries intervention (untreated enamel) Demineralised lesion depth · Human tooth enamel specimens, sound/intact (in vitro) · After cariogenic acid challenge / pH cycling Effect of Er:YAG Laser Irradiation on Preventing Enamel Caries: A Systematic Review and Meta-Analysis. (2024) | SMD -0.55 [-0.97, -0.12] | 3 studies · 252 participants | Ungraded |
Prophylaxis (teeth cleaning) and CHX or iodine-NaF solution application in the dentition of women (mothers) vs Placebo Adverse events for mother or child · 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 | Two trials (Dasanayake 1993; Dasanayake 2002) reported adverse events related to topical application of the treatment solutions (other data). | 2 studies | Ungraded |
Breastfeeding for <12 months vs Breastfeeding for ≥12 months Dental caries (early childhood caries) · Preschool children (<6 years) · Cohort studies Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | RR 0.65 [0.50, 0.86] | 8 studies · 4365 participants | Ungraded |
Significant salivary microbial (Lactobacillus) load vs No/low significant microbial load Dental caries · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 3.82 [3.439, 4.192] | NR | Ungraded |
Silver diamine fluoride (SDF) vs Silver nitrate 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 |
Occlusal splint vs Another occlusal splint with a different mechanism of action Muscle pain when chewing · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 2 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Teledentistry diagnosis using DSLR or smartphone extra-oral photographs vs Visual or clinical examination Positive predictive value 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) | no estimate extracted | 10 studies | Ungraded |
Prophylaxis (teeth cleaning) and CHX or iodine-NaF solution application in the dentition of women (mothers) vs Placebo dmft 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 | dmft was listed in the SoF table but not assessed (no trial reported it). | 0 studies | No studies |
Superelastic NiTi arch wire vs Conventional (stabilised) NiTi 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 | Time to alignment: not reported | 0 studies | No studies |
Extraction at patient age 11-12 years vs Extraction at patient age 8-10 years 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 0.82 [0.35, 1.88] | 2 studies | Ungraded |