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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 |
|---|---|---|---|
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Frequency of mouth cleaning · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Slum/disadvantaged vs non-slum/urban Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Mouth cleaning was mostly once daily and in the mornings; only a small proportion cleaned at least twice daily (e.g., Osuh 24% slum vs 27% non-slum; Singh 3%; Habib 3.5%; Hewlett 69%). A similar slum/disadvantaged vs… | NR | Ungraded |
Opal Seal fluoride-releasing adhesive 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) | The WSL volume was lower in the Opal Seal group than in the Clearfil and Transbond XT groups, but there was no significant difference among the groups (p > 0.05). | 1 study · 15 participants | Ungraded |
Advice about a healthy diet (including breastfeeding promotion and sugar avoidance) and feeding practices (e.g. relating to bottle-feeding and sleep) for infants and young children vs Standard care Caries severity (d1 + mfs >= 5) · For interventions, pregnant women, mothers or other caregivers of infants in the first year of life; for outcomes,… · Children assessed at 4 yrs Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | RR 0.68 [0.50, 0.92] | 1 study · 340 participants | Ungraded |
Moderate-severe active dental caries (exposure) vs Caries-free or mild dental caries (control) Salivary IL-8 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 57.20 [-18.60, 133.00] | 7 studies · 522 participants | Ungraded |
Farzanegan 2021 = Transbond XT + 1% chitosan + 1% TiO2 (co-intervention); Mollabashi 2022 = TiO2-only composite (1 wt%) vs Conventional adhesive/composite (Transbond XT) Enamel demineralization / white spot lesion prevention (DIAGNOdent, enamel mineral content) · Patients undergoing fixed orthodontic (fixed appliance) treatment (adolescents and adults, ages 12 to 35) · 1 day to 6 months Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Two RCTs (Farzanegan 2021 n=24; Mollabashi 2022 n=40): Mollabashi reported DIAGNOdent readings significantly lower on the TiO2 side than the control side (p<0.001); Farzanegan reported no significant difference in… | 2 studies · 64 participants | Ungraded |
Started toothbrushing with fluoride toothpaste at or before 12 months (earlier start) vs Started after 12 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 0.98 [0.81, 1.18] | 2 studies · 260 participants | Very low |
More than 15 missing teeth vs 15 or fewer missing teeth Oral cancer risk · People with and without more than 15 missing teeth · Missing teeth >15 Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | OR 1.91 [1.01, 3.62] | 5 studies | Ungraded |
Silver diamine fluoride (SDF) vs Restoration (restorative treatment) 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 |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Patient satisfaction · 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 |
Calcium fluoride nanoparticle (nCaF2)-containing orthodontic primer vs Conventional primer (Transbond) Enamel demineralization / white spot lesions (DIAGNOdent, photographic scoring) · Patients undergoing fixed orthodontic (fixed appliance) treatment (adolescents and adults, ages 12 to 35) · 1, 3 and 6 months (during treatment to debonding) Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Al Tuma 2023 (1 split-mouth RCT, 31 patients / 310 teeth): DIAGNOdent scores significantly favored the nCaF2 primer at 1, 3 and 6 months (p=0.000) and S. mutans count differed at 1 month; no significant difference in… | 1 study · 31 participants | Ungraded |
Intervention NR Decayed surfaces (DS) · 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 1.12 [1.00, 1.25] | 1 study | Ungraded |
Non-surgical orthodontic treatment (any: facemask, chin cup, tandem traction bow, mandibular headgear, ORTA, reverse Twin Block, Reverse Forsus) vs No treatment ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment (9 to 15 months) Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 3.05 [2.40, 3.71] | 8 studies · 345 participants | Moderate |
Institutionalization (living in an orphanage/institution) vs Parented children living with their families Permanent-teeth caries experience (DMF/DMFT, mean score) · Institutionalized orphan children (roughly 3 to 18 years) · Overall (pooled) Caries in orphan children: prevalence and determinants-a systematic review and meta-analysis. (2024) | MD 0.09 [-0.36, 0.55] | 7 studies · 2676 participants | Very low |
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 Percussion pain at 7 days · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 7 days Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | MD 0.06 [-0.29, 0.41] | 1 study · 41 participants | 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 recurrent periodontitis, receiving supportive (maintenance) periodontal care · 3 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD -0.01 [-0.27, 0.25] | 2 studies · 37 participants | Ungraded |
Intralesional dexamethasone injections vs Placebo injections 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 -2.10 [-6.77, 2.57] | 1 study · 25 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 Child oral health behaviour · 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 | Data on oral health behaviours from Lapinleimu 1995 (other data) showed no evidence of a difference between groups. | 1 study | Ungraded |
AA+GG (homozygous) genotypes vs GA (heterozygous) genotype Dental caries · Children (<18 years) with vs without dental caries · Over-dominant model (AA+GG vs GA), 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 0.85 [0.48, 1.49] | 3 studies · 1329 participants | Ungraded |
Obesity vs Normal weight (eutrophic) Dental caries prevalence (any DMFT), dichotomous · 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) | OR 2.53 [1.49, 4.29] | 2 studies · 659 participants | Moderate |
Intralesional dexamethasone injections vs Placebo injections 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 -1.80 [-6.30, 2.70] | 1 study · 25 participants | Very low |
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, Irreversible pulpitis Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.824 [0.746, 0.890] | NR | 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 Quality of life · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | No studies reported data for this outcome. | NR | No studies |
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) · Gini index: no inequalities A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 3.95 | NR | Ungraded |
Breastfeeding <18 months vs Breastfeeding ≥18 months Dental caries (ECC) · Preschool children under 6 years of age · First dental examination before age 6 years, Cohort studies; sensitivity analysis excluding studies 48 and 52 Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | RR 0.26 [0.16, 0.42] | 3 studies | Ungraded |
Missing teeth / tooth loss vs Fewer or no missing teeth Oral cancer (OC) · Adults in case-control studies of oral cancer · Not specified, Overall (all missing-teeth measures pooled) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | OR 1.20 [0.97, 1.48] | 6 studies | Ungraded |
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, Children's age: >3 years Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.83 [1.53, 2.18] | 5 studies | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Oral disease burden, slum vs non-slum urban comparison · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Slum vs non-slum urban / general population Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Five studies compared slum with non-slum urban or national populations: Airen 2014 (caries 76% slum vs 50-60% general), Patel 2017 and Osuh 2022 (higher oral disease prevalence in slum vs non-slum urban sites), Singh… | 5 studies | Ungraded |
Genome-wide common variants (additive dosage; present-study GWAS) vs Genome-wide significance threshold (P<5E-8) Dental caries - genome-wide-significant loci · Japanese adults (present-study cohort: 30,859 dental caries cases / 14,666 controls) · Lifelong (germline genotype), Present-study GWAS (Japanese) Genome-wide association meta-analysis identifies two novel loci associated with dental caries. (2024) | In the present Japanese GWAS, no loci reached genome-wide significance (P<5E-8) for dental caries; several loci reached the suggestive level (P<1E-5). Top-associated variant rs140784657 (intergenic). All 47 lead… | 1 study · 45525 participants | Ungraded |
Second molar mesially inclined at extraction vs Second molar upright 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 0.68 [0.27, 1.71] | 3 studies | Ungraded |
Breastfeeding (exclusive or partial, any duration) vs No breastfeeding 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 0.98 [0.77, 1.26] | 10 studies · 8506 participants | Ungraded |
Silver diamine fluoride (SDF; 38% in most trials, 30% in three) vs Other methods (pooled: ART/glass ionomer cement, nano-silver fluoride, sodium fluoride varnish) 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, Overall (all comparators pooled) The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024) | OR 1.74 [0.88, 3.46] | 5 studies · 743 participants | Moderate |
Breastfeeding for <4 months vs Breastfeeding for ≥4 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 0.95 [0.80, 1.13] | 2 studies · 1017 participants | Ungraded |
Facemask with rapid maxillary expansion (RME) vs Reverse Forsus 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 0.46 [-0.90, 1.82] | 1 study · 30 participants | Ungraded |
Intervention NR Cariogenic microbiota counts (Streptococcus mutans, Lactobacillus spp.) · Narrative synthesis: significantly higher in CLP vs controls (Ahluwalia, Lucas, Hassani, Cheng, Sundell) Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | no estimate extracted | 5 studies | Ungraded |
Intervention NR Overall success (composite of clinical and radiographic success) · Immature teeth, normal pulp/reversible pulpitis Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.892 [0.834, 0.940] | 2 studies | Ungraded |
Silver diamine fluoride (SDF) vs Restoration (restorative treatment) Dental pain or sensitivity · Children and adults (with or without carious lesions) · 12 months, Children Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | OR 9.14 [0.49, 172.21] | 1 study · 69 participants | Very low |
nCaF2 primer vs Control Transbond primer Photographic white spot lesion score · 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 significant differences in the WSLs photographic scores of the control group with the contralateral nCaF2 group before and after bonding. | 1 study · 31 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) · Overall (all regions) A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 49 [44, 55] | 67 studies | Ungraded |
Silver diamine fluoride (SDF) vs Silver nitrate plus fluoride varnish 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 |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Any adverse effect related to aPDT · 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 |
Cesarean section delivery vs Vaginal delivery Early childhood caries (ECC) · Children with average age ≤3 years · Average age: ≤3 years RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024) | OR 0.86 [0.67, 1.10] | 10 studies | Ungraded |
Obesity 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 -0.34 [-0.96, 0.27] | 2 studies · 710 participants | Very low |
Surgery plus Heister jaw opener vs Surgery plus wooden tongue depressors Burning sensation (VAS 0-100) · 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 | Vadepally 2019 measured burning sensation on a VAS but did not fully report results, stating there was no significant difference between the 2 groups (p=0.617). | 1 study · 50 participants | Ungraded |
Consumption of xylitol chewing gum by women (mothers) vs Consumption of CHX/xylitol gum by women, or CHX varnish applied to women's dentition dmfs 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 | dmfs was listed in the SoF table but not assessed (not reported for this comparison). | 0 studies | No studies |
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, Children's age: <=3 years Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.70 [1.50, 1.91] | 7 studies | Ungraded |
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, Sample size: >1000 and ≤3000 Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.70 [1.48, 1.88] | 7 studies | Ungraded |
Oxitard (antioxidant) vs Aloe vera gel Difficulty in speech (participant-reported proxy) · 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 | OR 0.32 [0.14, 0.76] | 1 study · 120 participants | Ungraded |
Advice about a healthy diet (including breastfeeding promotion and sugar avoidance) and feeding practices (e.g. relating to bottle-feeding and sleep) for infants and young children vs Standard care Mother self-reported oral health behaviours and attitudes · 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 | One trial (Watt 2009) reported mother self-reported oral health behaviours (other data): some benefit in favour of the intervention. | 1 study | Ungraded |
Experimental orthodontic adhesive containing amorphous fluorinated calcium phosphate nanoparticles (n-AFCP) vs Conventional/control orthodontic adhesive (e.g., Transbond XT) or negative control Enamel remineralization extent and color change · Human enamel specimens around orthodontic brackets (in vitro) · pH cycling 21 days, Overall Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024) | A study using an orthodontic primer containing amorphous fluorinated calcium phosphate nanoparticles showed statistically significant remineralization and less enamel color change (delta-E) compared with the control… | 1 study | Ungraded |
Single-strand superelastic NiTi arch wire vs Coaxial superelastic NiTi arch wire 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 |