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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.
5,762 questions in 263 reviews · Dental caries
current versionsNo studies 321 · 5.6%Ungraded 4,450 · 77.2%Very low 455 · 7.9%Low 297 · 5.2%Moderate 200 · 3.5%High 39 · 0.7%
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 |
|---|---|---|---|
Pulp-status assessment method Pulp necrosis incidence · Vital teeth · Objective Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 5.66 [3.71, 7.99] | 24 studies · 6581 participants | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Birpou,2019 [25]; model performance 13 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.62 [1.12, 2.35] | 1 study | Ungraded |
Vitamin D deficiency (serum 25(OH)D < 50 nmol/L) vs Normal vitamin D level (serum 25(OH)D ≥ 50 nmol/L) Dental caries · Children (<19 years) · Case-control studies Correlation between vitamin D levels in serum and the risk of dental caries in children: a systematic review… (2023) | RR 1.05 [1.00, 1.09] | 3 studies | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Gao,2013 [29]; model performance 3 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 3.0 [2.36, 3.82] | 1 study | Ungraded |
Elective neck dissection (at time of primary tumour resection) vs Therapeutic (delayed) neck dissection Mortality (overall survival) · Adults with oral cavity cancer (tongue or floor of mouth) and clinically negative neck nodes · 3 years Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | HR 0.64 [0.50, 0.83] | 4 studies · 883 participants | Moderate |
Gingivitis (assessed by gingival index or WHO criteria) vs Individuals without gingivitis Oral health-related quality of life (dichotomous: poor vs not) · Indians (adolescents, adults, elderly, children) Impact of oral conditions on oral health-related quality of life among Indians- a systematic review and… (2023) | Gingivitis vs no gingivitis: studies show inconsistency; one study showed poor QoL (Shivakumar 2018, OR 1.39, 95% CI 1.09 to 1.67), two studies no significant association (Baiju 2019, Singh 2020); 943 participants, 3… | 3 studies · 943 participants | Very low |
Sentinel node biopsy (neck dissection only if biopsy positive) vs Elective neck dissection Disease-free survival (new disease, progression, and mortality) · Adults with oral cavity or oropharyngeal cancer · 3 years Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | HR 0.98 [0.90, 1.07] | 1 study · 279 participants | Low |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Hänsel Petersson,2015 [30]; model performance 4 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.93 [0.89, 0.97] | 1 study | Ungraded |
Gum chewing (sugar-free) vs No gum chewing (control) Self-reported xerostomia / symptoms of dry mouth · Elderly (>60 years) and medically compromised adults with xerostomia / dry mouth · Various (single session to 3 months) The effect of gum chewing on xerostomia and salivary flow rate in elderly and medically compromised… (2023) | Narrative vote-count: of 17 studies measuring self-reported xerostomia / dry mouth, 12 found a positive effect of gum chewing [18,19,21,23,24,25,26,27,30,31,38,40] and 5 detected no effect [17,29,33,34,37]. No study… | 17 studies | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Beck,1992 [24]; model performance 6 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 2.27 [1.95, 2.64] | 1 study | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Fontana,2011 [16]; model performance 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.90 [1.57, 2.31] | 1 study | Ungraded |
Superselective neck dissection vs Selective neck dissection Locoregional recurrence · Adults with oral cavity cancer (tongue or floor of mouth) and clinically negative neck nodes Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Locoregional recurrence: data not presented usably and inconsistent; Pandey 2018 no difference (3/12 vs 3/20); Rastogi 2018 lower recurrence with superselective (Kaplan-Meier P<0.05); 72 participants (2 RCTs). | 2 studies · 72 participants | Very low |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Disney,1992 [15]; model performance 2 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.49 [0.42, 0.57] | 1 study | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Christian,2020 [27]; model performance 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.74 [0.42, 1.31] | 1 study | Ungraded |
Indirect restorations (crowns, fixed partial dentures, inlays/onlays/veneers) vs None (single-group incidence) Pulp necrosis · Vital teeth restored with indirect restorations · Follow-up ≤5 to >10 years, Objective pulp-status assessment Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 5.66 [3.71, 7.99] | 6581 participants | Ungraded |
Chlorhexidine (CHX) mouthwash (adjunct to mechanical cleaning) vs Blank control (no mouthwash; before-after comparison) Total bacteria (colony count) · Orthodontic patients (any age) undergoing orthodontic treatment (mostly fixed appliances) · <=3 months (short-term) The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | Colony count of total bacteria were significantly reduced compared to placebos according to two studies [34, 43]. | 2 studies | Very low |
Tooth location Pulp necrosis incidence · Vital teeth · Kontakiotis et al. 2015 mandibular anterior Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 11.8 | 1 study | Ungraded |
Elective neck dissection (at time of primary tumour resection) vs Therapeutic (delayed) neck dissection Disease-free survival (new disease, progression, and mortality) · Adults with oral cavity cancer (tongue or floor of mouth) and clinically negative neck nodes · 3 years Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | HR 0.56 [0.45, 0.70] | 5 studies · 954 participants | Moderate |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Birpou,2019 [25]; model performance 7 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.68 [0.50, 0.93] | 1 study | Ungraded |
CPP-ACFP vs Control (placebo / no active therapy) Remineralization / reduction in lesion severity (change in QLF, laser fluorescence, or lesion area) · Patients with white spot lesions / early caries lesions (WSLs/ECLs), including orthodontic and non-orthodontic… Comparison of therapies of white spot lesions: a systematic review and network meta-analysis. (2023) | SMD -0.42 [-0.84, 0.00] | 5 studies | Ungraded |
Glass ionomer cement (GIC) vs Resin composite (RC) Secondary caries (occurrence) · Patients requiring dental restoration; permanent teeth · 1 year of follow-up Clinical efficacy of bioactive restorative materials in controlling secondary caries: a systematic review… (2023) | RR 0.33 [0.10, 1.05] | 5 studies · 380 participants | Low |
Surgery plus radiotherapy vs Radiotherapy alone Adverse events associated with treatment · Adults with oral cavity or oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Adverse events: severe acute effects in both groups (subcutaneous fibrosis, telangiectasia, moderate-to-severe oedema, xerostomia, trismus, dysphagia); subcutaneous fibrosis more prevalent with surgery + radiotherapy… | 1 study · 35 participants | Very low |
Strategies to integrate oral health into primary care (e.g., training/education of non-dental primary care professionals, policy/financing and health-insurance changes, colocation of dental and medical services, interprofessional and community-health-worker collaboration, teledentistry, integrated oral health assessment tools, school-based activities) vs No integration / usual care (or pre-integration baseline; many included studies uncontrolled) Oral disease outcomes, including dental caries estimates · People of all ages and abilities served through primary care and related settings (children, pregnant women, older… Strategies to integrate oral health into primary care: a systematic review. (2023) | Nine studies reported oral disease outcomes, seven of which measured change in dental caries estimates. Eight of the nine studies reported improved oral disease outcomes; one (Vichayanrat 2012) reported no change in… | 9 studies | Ungraded |
Clear aligners (CA) vs Conventional fixed orthodontic appliances (CF) Plaque accumulation (Plaque Index) · Orthodontic patients undergoing comprehensive treatment (late mixed or permanent dentition, no active caries) · 12 months, Follow-up: 12 months White spot lesions, plaque accumulation and salivary caries-associated bacteria in clear aligners compared… (2023) | SMD -2.14 [-3.64, -0.64] | 3 studies · 113 participants | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Disney,1992 [15]; model performance 4 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.45 [0.38, 0.54] | 1 study | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Gao.2010 [17]; model performance 4 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 10.26 [8.20, 12.84] | 1 study | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Pang,2021 [19]; model performance 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 1.13 [0.96, 1.33] | 1 study | Ungraded |
Older age vs Younger age Oral health-related quality of life · Adolescents aged 10-19 years Oral-health-related quality of life in adolescents: umbrella review. (2023) | no estimate extracted | NR | Ungraded |
Indirect restorations (crowns, fixed partial dentures, inlays/onlays/veneers) vs None (single-group incidence) Pulp necrosis · Vital teeth restored with indirect restorations · Follow-up ≤5 to >10 years, Fixed partial dentures (FPD) Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 5.01 [2.76, 7.88] | 15 studies · 4674 participants | Ungraded |
Tooth location Pulp necrosis incidence · Vital teeth · Kontakiotis et al. 2015 maxillary posterior Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 7.5 | 1 study | Ungraded |
Self-assembling peptide P11-4 vs CPP-ACFP Remineralization / reduction in lesion severity (change in QLF, laser fluorescence, or lesion area) · Patients with white spot lesions / early caries lesions (WSLs/ECLs), including orthodontic and non-orthodontic… Comparison of therapies of white spot lesions: a systematic review and network meta-analysis. (2023) | SMD -0.13 [-0.68, 0.42] | 2 studies | Ungraded |
Bruxism vs No bruxism Oral health-related quality of life · Adolescents aged 10-19 years Oral-health-related quality of life in adolescents: umbrella review. (2023) | no estimate extracted | NR | Ungraded |
Surgery plus adjuvant radiotherapy vs Chemotherapy (chemoradiotherapy) Locoregional recurrence · Adults with oral cavity or oropharyngeal cancer · oral cavity Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Locoregional recurrence: reported difference between groups not statistically significant (P=0.355), but no useable data; 32 participants (1 RCT, Iyer 2015). | 1 study · 32 participants | Very low |
Herbal mouthwash vs Blank control Gingival inflammation-related index · Orthodontic patients · ≤ 3 months The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | CPI was significantly reduced compared to baseline [35]; SBI was significantly reduced while MGI was similar compared to baseline [45]; BOP was significantly reduced compared to blank control [39]. | 3 studies | Very low |
Intervention NR Confidence Strategies to integrate oral health into primary care: a systematic review. (2023) | 3 of 3 studies reported favourable outcomes | 3 studies | Ungraded |
PET-CT following chemoradiotherapy (neck dissection only if no/incomplete response) vs Planned neck dissection before or after chemoradiotherapy Adverse events associated with treatment · Adults with oral cavity or oropharyngeal cancer with nodal disease (stage N2 or N3) Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Adverse events: 22 surgical complications in the PET-CT group vs 83 in the planned-surgery group (Mehanna 2017). | 1 study · 564 participants | Very low |
Prosthetic need vs Individuals without prosthetic need Oral health-related quality of life (continuous), measured by GOHAI · Indian elderly and general-population adults Impact of oral conditions on oral health-related quality of life among Indians- a systematic review and… (2023) | Prosthetic need and QoL (continuous, GOHAI): of three studies, one found no significant difference (Shetty 2013) and two proved the association (Pillai 2015, Rekhi 2018). Not pooled. | 3 studies | Ungraded |
PET-CT following chemoradiotherapy (neck dissection only if no/incomplete response) vs Planned neck dissection before or after chemoradiotherapy Disease-free survival · Adults with oral cavity or oropharyngeal cancer with nodal disease (stage N2 or N3) Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Disease-free survival: outcome not reported in a usable way (Mehanna 2017: disease-specific and other-cause mortality did not differ, P=0.80 and 0.41). | 1 study | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Gao,2013 [29]; model performance 8 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.04 [1.0, 1.08] | 1 study | Ungraded |
Herbal mouthwash vs Blank control Cariogenic bacteria (Mutans streptococci) · Orthodontic patients · ≤ 3 months The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | Colony count of MS was significantly reduced compared to baseline [48]; another study found an insignificant reduction compared to baseline [51]. | 2 studies | Very low |
Dental (tooth) agenesis vs No dental agenesis Oral health-related quality of life (OHRQoL) · Adolescents (10-19 years) Oral-health-related quality of life in adolescents: umbrella review. (2023) | tooth agenesis does not have enough scientific evidence to support a relationship between OHRQoL [41]. No articles were found that had evaluated children and adolescent. Only one was found to have a greater impact in… | NR | Ungraded |
Mutans streptococci detected in plaque or saliva at baseline vs No mutans streptococci detected in plaque or saliva at baseline Development of carious lesions · Children younger than 6 years with caries-free primary dentition · 6 months to 3.5 years, Overall sample sensitivity analysis Is Mutans Streptococci count a risk predictor of Early Childhood Caries? A systematic review and… (2023) | OR 4.04 [3.33, 4.90] | 12 studies · 3313 participants | Ungraded |
Elective radical (comprehensive) neck dissection vs Elective selective neck dissection Disease-free survival (new disease, progression, and mortality) · Adults with oral cavity cancer · 5 years Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | HR 0.57 [0.29, 1.11] | 1 study · 104 participants | Very low |
Outer carious dentin vs Inner carious dentin MMP-20 expression · Human carious dentin Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023) | no estimate extracted | 1 study · 5 participants | Moderate |
Severe traumatic dental injury with pulp exposure or tooth darkening vs No traumatic dental injury Oral health-related quality of life · Adolescents aged 10-19 years Oral-health-related quality of life in adolescents: umbrella review. (2023) | no estimate extracted | NR | Ungraded |
Multivariable prediction model of caries increment (>=3 predictors), e.g. logistic-regression or algorithm-based caries-risk models vs Alternative prediction model(s) within the same study, or no formal comparator (models compared descriptively; no between-model statistical test) Predictive performance for coronal caries increment (negative likelihood ratio, LR-) · Children and adolescents (aged 2-19) at risk of coronal caries increment (caries onset or progression) · Follow-up >=1 year (included studies 1-5 years), Model validation studies Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | No meta-analysis. Per-model LR- (Table 2) across the 9 validation studies ranged from about 0.14 to 1.13 (e.g. Gao 2013 NUS-CRA 0.26, CAMBRA 0.14-0.31, CAT up to ~1.10; Campus 0.20; Pang 2020 low-risk 1.13). Overall… | 9 studies | Ungraded |
Skin color / ethnicity vs Reference skin color / ethnicity Oral health-related quality of life (OHRQoL) · Adolescents (10-19 years) Oral-health-related quality of life in adolescents: umbrella review. (2023) | Biological data such as skin color and age have no concrete evidence about this impact in the OHRQoL. Important aspects like gender and skin color did not have their level of impact clarified. | NR | Ungraded |
Indirect restorations vs None Pulp necrosis incidence · Vital teeth · ≤ 5 years, ≤ 5 years Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 3.53 [2.10, 5.31] | 5532 participants | Low |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Hänsel Petersson,2010 [31]; model performance 2 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.58 [1.38, 1.82] | 1 study | Ungraded |
Fluoride toothpaste use vs None (descriptive single-group pooled prevalence) Fluoride toothpaste use prevalence (among children with caries) · Children with dental caries (deciduous and/or permanent dentition) in low- and middle-income countries Individual, Family, and Socioeconomic Contributors to Dental Caries in Children from Low- and Middle-Income… (2022) | Prevalence 0.391 [0.1658, 0.644] | 2 studies | Ungraded |