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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.
239 questions in 37 reviews · cluster CL0069
current versionsNo studies 4 · 1.7%Ungraded 170 · 71.1%Very low 42 · 17.6%Low 6 · 2.5%Moderate 10 · 4.2%High 7 · 2.9%
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.
Intervention categories, outcome domains and clusters are a proposed key pending human validation. Clear all filters
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Dental caries (presence or experience) vs Adolescents without dental caries Negative oral-health impact on daily performance measured by Child-OIDP · Adolescents aged 10 to 19 years · Cross-sectional (concurrent exposure and outcome); oral impacts recalled over the prior 6 months, Instrument subgroup: Child-OIDP Impact of dental caries on the quality of life of adolescents: A systematic review and meta-analysis. (2025) | PR 1.66 [1.19, 2.31] | 6 studies | Ungraded |
E-cigarette use (ENDS / vaping) vs Non-smokers Interleukin-8 (IL-8) · Humans who use e-cigarettes (mostly adults, often with periodontal disease) assessed for oral proinflammatory markers · Cross-sectional (single time point) for most; a few 6-month prospective, Overall (saliva + GCF) The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d -0.43 [-1.02, 0.14] | 6 studies | Ungraded |
Veillonella spp. abundance Future caries · Children without a previous history of caries A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | Among children without a previous history of caries, Veillonella spp., but not S. mutans or other acid-producing species, predicted future caries. | 1 study · NA (subgroup without prior caries history; n not reported) participants | Ungraded |
Electronic cigarette use vs Non-smokers TNF-α level · People who use electronic cigarettes · Saliva The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.23 [-0.62, 1.09] | 5 studies | Ungraded |
E-cigarette use (ENDS / vaping) vs Non-smokers Interleukin-6 (IL-6) · Humans who use e-cigarettes (mostly adults, often with periodontal disease) assessed for oral proinflammatory markers · Cross-sectional (single time point) for most; a few 6-month prospective, Overall (saliva + GCF) The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.83 [-0.16, 1.79] | 6 studies | Ungraded |
Children with dental caries vs Children without dental caries (caries-free) Mean corpuscular volume (MCV) · Children and adolescents (0-18 years; most included reviews focused on <6 years) Association Between Iron Deficiency Anemia and Dental Caries in Children: A Systematic Umbrella Meta-Analysis. (2025) | MD -1.96 [-4.02, 0.10] | 3 studies | Very low |
Electronic cigarette use vs Non-smokers IL-6 level · People who use electronic cigarettes · GCF The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 1.43 [0.76, 2.10] | 1 study | Ungraded |
Electronic cigarette use vs Non-smokers TNF-α level · People who use electronic cigarettes · GCF The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 2.19 [1.53, 2.84] | 2 studies | Ungraded |
E-cigarette use (ENDS / vaping) vs Non-smokers Dry mouth (xerostomia) · Humans who use e-cigarettes (adolescents to adults) assessed for dental caries · Cross-sectional to 12 months The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Narrative synthesis. E-cigarette users reported dry mouth more frequently than non-smokers: Chaffee 2021 dry mouth 12% (OR 1.4); Alhajj 2022 dry mouth 33.3% in e-cigarette users vs 23.4% in controls. Not pooled. | 2 studies | Ungraded |
Electronic cigarette use vs Non-smokers IL-6 level · People who use electronic cigarettes · Saliva The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.78 [-0.56, 1.98] | 5 studies | Ungraded |
Dental caries (presence or experience) vs Adolescents without dental caries Negative oral-health impact on daily performance measured by OIDP · Adolescents aged 10 to 19 years · Cross-sectional (concurrent exposure and outcome); oral impacts recalled over the prior 6 months, Instrument subgroup: OIDP (all 3 studies) Impact of dental caries on the quality of life of adolescents: A systematic review and meta-analysis. (2025) | PR 1.68 [0.89, 3.17] | 3 studies | Ungraded |
Electronic cigarette use vs Non-smokers TNF-α level · People who use electronic cigarettes · Overall The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.66 [-0.16, 1.43] | 7 studies | Ungraded |
Dental caries (presence or experience) vs Adolescents without dental caries Negative oral-health impact on daily performance measured by OIDP · Adolescents aged 10 to 19 years · Cross-sectional (concurrent exposure and outcome); oral impacts recalled over the prior 6 months, Instrument subgroup: OIDP, sensitivity analysis excluding Krisdapong et al. Impact of dental caries on the quality of life of adolescents: A systematic review and meta-analysis. (2025) | PR 1.21 [1.15, 1.28] | 2 studies | Ungraded |
Electronic cigarette use vs Non-smokers IL-1β level · People who use electronic cigarettes · Saliva The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.87 [-0.33, 2.08] | 9 studies | Ungraded |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Clinical Attachment Level (CAL) · Individuals assessed for periodontal health (mainly children and adolescents, age >2 years) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | The loss of clinical attachment level (CAL) is greater in patients with cleft lip and palate than in healthy controls (p < 0.00001) | NR | Ungraded |
Dental caries (presence or experience) vs Adolescents without dental caries Negative oral-health impact on daily performance (OIDP or Child-OIDP) · Adolescents aged 10 to 19 years · Cross-sectional (concurrent exposure and outcome); oral impacts recalled over the prior 6 months, Overall (all meta-analyzed studies pooled; both instruments and both caries definitions) Impact of dental caries on the quality of life of adolescents: A systematic review and meta-analysis. (2025) | PR 1.52 [1.15, 2.01] | 9 studies | Ungraded |
Electronic cigarette use vs Non-smokers IL-6 level · People who use electronic cigarettes · Overall The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.83 [-0.16, 1.79] | 6 studies | Ungraded |
E-cigarette use (ENDS / vaping) vs Non-smokers Tumour necrosis factor-alpha (TNF-α) · Humans who use e-cigarettes (mostly adults, often with periodontal disease) assessed for oral proinflammatory markers · Cross-sectional (single time point) for most; a few 6-month prospective, Overall (saliva + GCF) The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.66 [-0.16, 1.43] | 7 studies | Ungraded |
Early childhood caries vs Caries-free controls Veillonella spp. relative abundance · Young children with early childhood caries and caries-free controls A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | Mean relative abundance (%) ECC 3.29 (SD 6.83) vs caries-free 2.13 (SD 2.30) | 1 study · 87 participants | Ungraded |
E-cigarette use (ENDS / vaping) vs Non-smokers Interleukin-1 beta (IL-1β) · Humans who use e-cigarettes (mostly adults, often with periodontal disease) assessed for oral proinflammatory markers · Cross-sectional (single time point) for most; a few 6-month prospective, Overall (saliva + GCF) The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.98 [-0.03, 1.99] | 11 studies | Ungraded |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Oral microbiota composition · Individuals assessed for oral microbiota (mainly children and adolescents) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | no estimate extracted | 8 studies | Ungraded |
Children with dental caries vs Children without dental caries (caries-free) Serum ferritin level · Children and adolescents (0-18 years; most included reviews focused on <6 years) Association Between Iron Deficiency Anemia and Dental Caries in Children: A Systematic Umbrella Meta-Analysis. (2025) | MD -3.96 [-8.48, 0.57] | 4 studies | Very low |
Electronic cigarette use vs Non-smokers IL-8 level · People who use electronic cigarettes · GCF The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | no estimate extracted | 1 study | Ungraded |
Lacunar stroke (cases) vs Without lacunar stroke (controls) Clinical attachment level (CAL) · Adults The contribution of oral infectious diseases in lacunar stroke based on meta-analysis and Mendelian… (2025) | MD 1.34 [0.63, 2.05] | 4 studies | Ungraded |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Probing Pocket Depth (PPD) · Individuals assessed for periodontal health (mainly children and adolescents, age >2 years) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | MD 0.88 [0.82, 0.95] | 3 studies · 340 participants | Low |
Severe early childhood caries vs Caries-free controls Veillonella spp. relative abundance · Children under 6 years with severe early childhood caries and caries-free controls A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | Mean relative abundance (%) caries 5.25 (SD 6.65) vs control 15.22 (SD 9.48); P=0.033 | 1 study · 9 (caries only; control not reported in Table 3) participants | Ungraded |
Electronic cigarette use vs Non-smokers IL-1β level · People who use electronic cigarettes · Overall The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.98 [-0.03, 1.99] | 11 studies | Ungraded |
Electronic cigarette use vs Non-smokers IL-8 level · People who use electronic cigarettes · Saliva The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d -0.32 [-0.99, 0.35] | 5 studies | Ungraded |
Children with dental caries vs Children without dental caries (caries-free) Haemoglobin level · Children and adolescents (0-18 years; most included reviews focused on <6 years) Association Between Iron Deficiency Anemia and Dental Caries in Children: A Systematic Umbrella Meta-Analysis. (2025) | MD -2.20 [-4.59, 0.19] | 3 studies | Very low |
Dental caries (ECC/severe ECC) as exposure/grouping vs Caries-free controls Relative abundance of Veillonella spp. · Individuals assessed for dental caries, predominantly children with early childhood caries (ECC) or severe ECC (age… A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | No meta-analysis was performed (too few studies). Across 7 studies the direction was inconsistent: Veillonella spp. relative abundance was higher in caries than in caries-free subjects in some studies (Setiawan 2020:… | 3 studies · 146 participants | Ungraded |
Electronic cigarette use vs Non-smokers IL-1β level · People who use electronic cigarettes · GCF The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 1.58 [-0.79, 3.94] | 2 studies | Ungraded |
Dental caries vs Without dental caries Lacunar stroke · Adults The contribution of oral infectious diseases in lacunar stroke based on meta-analysis and Mendelian… (2025) | No studies addressing the association between dental caries and LS were identified. | 0 studies | No studies |
Anorexia nervosa (as exposure; diagnosed by DSM-III/III-R/IV/V) vs Healthy individuals without anorexia nervosa (age- and sex-matched controls) Dental erosion · Patients with anorexia nervosa aged >=12 years (mean age ~18.4; entirely female in reported data), general… The influence of anorexia nervosa on oral health and related parameters potentially relevant to orthodontic… (2025) | Significant prevalence of dental erosion in anorexic patients vs controls, though BEWE scores indicated low erosive-wear risk (Mascitti BEWE 5.2+/-4.5; Paszynska 16.2% at BEWE 3-8); not meta-analyzed | 2 studies · 270 participants | Ungraded |
Electronic cigarette use vs Non-smokers IL-8 level · People who use electronic cigarettes · Overall The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d -0.43 [-1.02, 0.14] | 6 studies | Ungraded |
Experience of dental caries (caries history, e.g. DMFT) vs Adolescents without dental caries Negative oral-health impact on daily performance (OIDP or Child-OIDP) · Adolescents aged 10 to 19 years · Cross-sectional (concurrent exposure and outcome); oral impacts recalled over the prior 6 months, Caries-definition subgroup: experience of dental caries Impact of dental caries on the quality of life of adolescents: A systematic review and meta-analysis. (2025) | PR 1.72 [1.23, 2.43] | 6 studies | Ungraded |
Severe early childhood caries vs Caries-free controls Veillonella dispar relative abundance · Children under 6 years with severe early childhood caries and caries-free controls A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2025) | Median relative abundance (%) caries 3.0 (range 0.33-19.0) vs control 2.2 (0.15-9.4) | 1 study · 50 participants | Ungraded |
Presence of dental caries vs Adolescents without dental caries Negative oral-health impact on daily performance (OIDP or Child-OIDP) · Adolescents aged 10 to 19 years · Cross-sectional (concurrent exposure and outcome); oral impacts recalled over the prior 6 months, Caries-definition subgroup: presence of dental caries Impact of dental caries on the quality of life of adolescents: A systematic review and meta-analysis. (2025) | PR 1.19 [0.77, 1.84] | 3 studies | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Ever utilised dental services · Adult residents of slums and non-slum urban settings of LMICs · Lifetime (ever), Slum vs non-slum; urban vs rural; by sex Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | The 'ever utilised' rate ranged from 17% to 71% across studies (e.g., Osuh 17% slum vs 24% non-slum; Habib 14.6%; Hewlett 34%; Morgan 70.6%; Olusile 26%; Masalu 50% urban vs 37% rural; Singh 23% male vs 41% female). | 10 studies | Ungraded |
Child has a disability (special needs) vs Parents/caregivers of children without disabilities Parental concern / caregiver stress indices (parental perception and parenting stress about the child's oral health) · Parents/caregivers of children with disabilities (special needs; autism spectrum disorder or unspecified disability)… · Cross-sectional Disabilities and Disparities in Oral Health-Related Quality of Life: A Systematic Review and Meta-Analysis… (2024) | SMD 0.43 [0.23, 0.63] | 3 studies · 472 participants | Ungraded |
Dental caries (DT not equal to 0) vs No dental caries Periodontitis (prevalence) · Adults · Adjusted OR Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.57 [1.32, 1.86] | 3 studies | Ungraded |
Slum setting vs Non-slum urban setting Dental service utilization · 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 | 10 studies | Ungraded |
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate) Prevalence of ICLs (mean number of lesions per subject) · Patients (permanent dentition) during or after fixed orthodontic treatment with fixed (multibracket) appliances · During or after fixed orthodontic treatment (cross-sectional/at debonding), Overall (random-effects model) Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024) | MEAN 2.24 [1.79, 2.70] | 6 studies · 484 participants | Very low |
Not applicable vs Not applicable Prenatal vitamin D deficiency prevalence · Pregnant mothers · Pregnancy, Overall Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024) | Proportion 0.32 | NR | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Dental service utilisation within the past year · Adult residents of slums and non-slum urban settings of LMICs · Past 12 months Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Utilisation within the preceding year ranged from 4% to 72% (e.g., Osuh 4%; Hewlett 10%; Rezaei 60% for treatment and 10% for check-ups; Olutola 72%). | NR | 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 |
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 |
Children with severe early childhood caries (S-ECC) vs Caries-free children Serum 25-hydroxyvitamin D level · Preschool children ≤6 years, Asia · Asia The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | MD -19.25 [-20.75, -17.76] | NR | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Proportion of ancient skulls with at least one non-carious cervical lesion (NCCL) · Ancient/prehistoric human skulls (excavated/archaeological skeletal remains) · Overall (all included studies) Investigation of the presence of Non-carious cervical lesions (NCCLs) in ancient adult skulls: analyzing… (2024) | Proportion 0.014 [0.001, 0.027] | 6 studies · 805 participants | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Dental trauma prevalence · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Urban vs rural; slum vs non-slum Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Dental trauma was more prevalent in urban than rural settings and among disadvantaged groups; Osuh 2022 reported 32% (slum) vs 21% (non-slum); Tobin & Ajayi 2017 found 87.5% of trauma cases in urban vs rural areas… | NR | Ungraded |
Oral cancer patients (cases) vs Healthy controls Alveolar bone loss (ABL) in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, ABL (alveolar bone loss) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 0.18 [-2.34, 2.69] | 2 studies | Ungraded |