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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 |
|---|---|---|---|
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Use of toothbrush and toothpaste for mouth cleaning · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Slum/disadvantaged/rural vs non-slum/urban Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Eleven studies addressed practices; toothbrush and toothpaste were the commonest cleaning method but their use was lower among slum/disadvantaged/rural groups than non-slum/urban groups (e.g., Osuh 78% slum vs 94%… | 11 studies | Ungraded |
Reduction in previous year's academic score vs No reduction in academic score Reduction in previous year's academic score · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 5.51 [1.952, 9.066] | NR | Ungraded |
Number of missing teeth (per additional tooth) vs One fewer missing tooth Oral cancer (OC) · Adults in case-control studies of oral cancer · Not specified, Missing teeth (per tooth) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | OR 0.96 [0.92, 1.01] | 2 studies | 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 |
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 |
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 |
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 |
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 |
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 |
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 |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Proportion of teeth with non-carious cervical lesions (NCCLs) in ancient skulls · 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 0.004 [0.001, 0.006] | 4 studies · 11578 participants | Ungraded |
Children with severe early childhood caries (S-ECC) vs Caries-free children Serum 25-hydroxyvitamin D level · Preschool children ≤6 years, North America · North America The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | MD -13.28 [-17.70, -8.87] | NR | Ungraded |
Slum setting vs Non-slum urban setting Oral disease prevalence · Adult residents of slum and non-slum urban settings in LMICs Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | no estimate extracted | 18 studies | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Self-perceived (self-rated) oral health status · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, By age, sex, socioeconomic class, employment Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Six studies (incl. 1 qualitative) reported perception; most participants rated their oral health as satisfactory/good (e.g., Olutola 76% good; Olusile 21% very good + 37% good; Osuh higher in slum than non-slum),… | 6 studies | Ungraded |
Children with severe early childhood caries (S-ECC) vs Caries-free children Serum 25-hydroxyvitamin D level · Preschool children ≤6 years The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | MD -18.64 [-20.06, -17.22] | 7 studies · 1658 participants | Ungraded |
Slum setting vs Non-slum urban setting Oral health practices · 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 | 11 studies | Ungraded |
Slum setting vs Non-slum urban setting Self-perceived oral health · 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 | 6 studies | Ungraded |
Children with early childhood caries (ECC) vs Caries-free children Serum 25-hydroxyvitamin D level · Preschool children ≤6 years The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | MD -13.96 [-19.88, -8.03] | 9 studies · 3444 participants | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Use of alternative/indigenous mouth-cleaning implements · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Rural/slum vs urban Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Alternative implements included toothpowder, chewing-stick, neem, charcoal, sand, snuff, salt, miswak, cotton wool and the fingers; native/indigenous tools were used more by rural and slum/disadvantaged residents than… | NR | Ungraded |
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate) Prevalence of ICLs (proportion of tooth surfaces affected) · 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) | Proportion 0.22 [0.14, 0.33] | 6 studies · 11583 participants | Very low |
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate) Prevalence of ICLs (proportion of subjects affected) · 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) | Proportion 0.57 [0.48, 0.65] | 13 studies · 1448 participants | Very low |
Dental caries (DT not equal to 0) vs No dental caries Periodontitis (prevalence) · Adults · Overall Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.79 [1.36, 2.35] | 5 studies | Ungraded |
Oral cancer patients (cases) vs Healthy controls Clinical attachment loss (CAL) in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, CAL (clinical attachment loss) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 1.94 [0.22, 3.66] | 2 studies | Ungraded |
Carious dentin vs Sound dentin Cathepsin K (CT-K) presence/activity · Human ex vivo carious dentin (mostly coronal), natural caries lesions Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | Higher intensity of immunodetection of CT-K was registered in carious dentin than in sound dentin (Vidal et al., 2014); GRADE was not applied to CT-K. | 1 study · 10 participants | Ungraded |
Carious dentin vs Sound dentin MMP-13 presence/activity · Human coronal carious dentin and sound dentin Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | no estimate extracted | 1 study · 13 participants | Very low |
Irradiated carious dentin vs Non-irradiated carious dentin MMP-2 expression/activity · Human ex vivo carious dentin (head/neck radiotherapy) Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | No significant difference in MMP-2 (gelatinase) expression or activity between irradiated and non-irradiated groups (Gomes-Silva et al., 2017a); GRADE not separately applied to this comparison. | 1 study · 36 participants | Ungraded |
Carious dentin vs Sound dentin MMP-8 presence/activity · Human ex vivo carious dentin (mostly coronal), natural caries lesions Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | Due to the conflicting results of the included studies, no effect direction was found so the evidence is very uncertain regarding the MMP-8 presence in carious vs. sound dentin. | 2 studies | Very low |
Carious dentin vs Sound dentin MMP-2 presence/activity · Human ex vivo carious dentin (mostly coronal), natural caries lesions Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | MMP-2 may be increased in carious dentin when compared to sound dentin, but the evidence is very uncertain. | 7 studies · 373 participants | Very low |
Carious dentin vs Sound dentin MMP-2 presence/activity · Human coronal carious dentin and sound dentin Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | no estimate extracted | 7 studies · 373 participants | Very low |
Carious dentin vs Sound dentin MMP-9 presence/activity · Human coronal carious dentin and sound dentin Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | no estimate extracted | 3 studies | Very low |
Carious dentin vs Sound dentin MMP-9 presence/activity · Human ex vivo carious dentin (mostly coronal), natural caries lesions Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | MMP-9 may be increased in carious dentin when compared to sound dentin, but the evidence is very uncertain. | 3 studies · 292 participants | Very low |
Root carious dentin vs Coronal carious dentin MMP-2 activity · Human root and coronal carious dentin Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | no estimate extracted | 1 study · 10 participants | Very low |
Outer carious dentin (by lesion depth/location) vs Inner carious dentin MMP-8 location/depth · Human ex vivo carious dentin Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | Mixed: Kuhn 2016 no statistical difference by location; Shimada 2009 higher MMP-8 in outer vs inner carious dentin (very low certainty) | 2 studies | Very low |
Mouth pain vs No mouth pain Body mass index-for-age z score · Children aged 1–6 years · Mouth pain The bi-directional relationship between growth stunting and early childhood caries: a rapid review. (2023) | MD 0.29 | 1 study · 593 participants | Ungraded |
Outer/shallower carious dentin vs Inner/deeper carious dentin MMP-9 location/depth · Human carious dentin Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | no estimate extracted | 3 studies | Very low |
Early childhood caries / severe early childhood caries vs Caries-free children Change in height-for-age z-score (adjusted model) · Children in early childhood (0-6 years) · ~9.73-month follow-up, Shen et al. 2019 (China; adjusted) The bi-directional relationship between growth stunting and early childhood caries: a rapid review. (2023) | Regression coefficient -0.02 [-0.04, 0.01] | 1 study · 1111 participants | Ungraded |
Before cavity sealing vs After cavity sealing MMP-8 expression/activity · Human carious dentin · 60 days after cavity sealing Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | no estimate extracted | 2 studies · 48 participants | Very low |
Carious dentin vs Sound dentin MMP-8 presence/activity · Human coronal carious dentin and sound dentin Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | no estimate extracted | 2 studies | Very low |
Root carious dentin vs Coronal carious dentin MMP-2 presence/activity · Human ex vivo carious dentin (coronal and root) Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | There is no difference in MMP-2 activity in root vs. coronal carious dentin; MMP-2 was present in both coronal and root dentin in all specimens (Toledano et al., 2010). The evidence is very uncertain. | 1 study · 10 participants | Very low |
Baseline caries vs Lower baseline caries Change in height-for-age z score · Preschool children · Mean follow-up 9.73 months, Unadjusted model The bi-directional relationship between growth stunting and early childhood caries: a rapid review. (2023) | coefficient -0.03 [-0.04, 0.01] | 1 study · 1111 participants | Ungraded |
Dentin caries vs Enamel caries Bacterial collagenolytic-protease gene expression · Coronal dentin and enamel caries samples Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | no estimate extracted | 1 study | Ungraded |
Carious dentin vs Sound dentin MMP-13 presence/activity · Human ex vivo carious dentin (mostly coronal), natural caries lesions Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | MMP-13 may be increased in carious dentin when compared to sound dentin, but the evidence is very uncertain (Loreto et al., 2014: more in coronal caries, p<0.05). | 1 study · 13 participants | Very low |
Early childhood caries / severe early childhood caries vs Caries-free children Growth stunting / low linear growth (height-for-age z-score) · Children in early childhood (0-6 years) · Tsang et al. 2019 (Nepal) The bi-directional relationship between growth stunting and early childhood caries: a rapid review. (2023) | The severity of child caries measured by the dmft index correlated with mouth pain and both chronic (stunting) and acute malnutrition (HAZ score) (p<0.0001). | 1 study · 836 participants | Ungraded |
Dental caries vs Caries-free CA VI activity · Participants with dental caries and caries-free participants Associations of the activity and concentration of carbonic anhydrase VI with susceptibility to dental… (2023) | SMD 0.87 [0.39, 1.36] | 7 studies · 411 participants | Ungraded |
Outer/shallower carious dentin vs Inner/deeper carious dentin MMP-2 location/presence · Human carious dentin Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | no estimate extracted | 4 studies | Very low |
Before cavity sealing vs After cavity sealing MMP-9 expression/activity · Human carious dentin · 60 days after cavity sealing Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | no estimate extracted | 2 studies · 48 participants | Very low |
Early childhood caries / severe early childhood caries vs Caries-free children Growth stunting / low linear growth (height-for-age z-score) · Children in early childhood (0-6 years) · Khanh et al. 2015 (Vietnam; pulp-involved caries) The bi-directional relationship between growth stunting and early childhood caries: a rapid review. (2023) | MD 0.66 | 1 study · 593 participants | Ungraded |
Irradiated carious dentin vs Non-irradiated carious dentin MMP-2 activity/expression · Human carious dentin from irradiated and non-irradiated subjects Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | no estimate extracted | 1 study · 36 participants | Ungraded |
Carious dentin before cavity sealing vs Carious dentin after cavity sealing MMP-8 expression/activity · Human ex vivo carious dentin under sealed cavities · Before vs after sealing (Kuhn 2016: 60 days follow-up) Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | MMP-8 may be increased in the dentin before when compared to dentin after cavity sealing; MMP-8 significantly reduced after 60 days of sealing (Kuhn et al., 2016; Chibinski et al., 2014). | 2 studies · 48 participants | Very low |
Irradiated carious dentin vs Non-irradiated carious dentin MMP-9 expression/activity · Human ex vivo carious dentin (head/neck radiotherapy) Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | MMP-9 predominantly positive in non-irradiated vs irradiated carious dentin (single study; ungraded) | 1 study · 36 participants | Ungraded |