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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.
10,375 questions in 429 reviews · Oral Health
current versionsNo studies 1,344 · 13%Ungraded 6,832 · 65.9%Very low 1,228 · 11.8%Low 613 · 5.9%Moderate 290 · 2.8%High 68 · 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 |
|---|---|---|---|
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 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.33 [0.28, 0.39] | 1 study | Ungraded |
Intervention NR Pulp necrosis · Reversible hydrocolloid impression material Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 1.19 | 1 study | Ungraded |
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 3 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.41 [0.29, 0.59] | 1 study | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Holgerson,2009 [32]; model performance 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.61 [0.40, 0.94] | 1 study | Ungraded |
Gum chewing (sugar-free) vs No gum chewing (control) Salivary flow rate, stimulated and/or unstimulated (narrative synthesis) · Elderly (>60 years) and medically compromised adults with xerostomia / dry mouth · Various (single session to 12 months) The effect of gum chewing on xerostomia and salivary flow rate in elderly and medically compromised… (2023) | Narrative vote-count: of 19 studies measuring stimulated and/or unstimulated saliva flow rate, 9 found a positive effect of gum chewing [17,18,22,24,27,35,36,38,39] and 10 detected no effect… | 19 studies | 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 development studies Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | No meta-analysis. Per-model LR- (Table 2) for the 8 development studies ranged roughly 0.11-0.94 (e.g. Angulo 0.94, Demers 0.14-0.40, Gao 2010 0.11-0.30). Overall across all 66 models LR- ranged 0.0-1.1; LR-<=0.20… | 8 studies | Ungraded |
Low level laser therapy (LLLT) vs Conventional orthodontic appliance treatment Patient perception of pain and discomfort (VAS 0 to 100 mm) · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment · Space closure / first visit Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | MD -0.4 [-1.87, 1.07] | 1 study · 37 participants | Very low |
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− 0.31 [0.09, 1.04] | 1 study | Ungraded |
Tooth location Pulp necrosis incidence · Vital teeth · Kontakiotis et al. 2015 maxillary anterior Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 9.4 | 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 7 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.44 [0.35, 0.56] | 1 study | Ungraded |
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 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.34 [1.26, 1.43] | 1 study | Ungraded |
Hawley removable retainer vs Clear plastic removable retainer Stability: Little's Irregularity Index (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | MD 0.01 [-0.65, 0.67] | 1 study · 30 participants | Very low |
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 |
Glass ionomer (GIC) permanent cement vs Glass ionomer cement or zinc phosphate cement Pulp necrosis incidence · Vital teeth · GIC Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 5.33 [2.56, 9.03] | 182 participants | 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 3 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.33 [0.25, 0.45] | 1 study | Ungraded |
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 4 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.51 [1.30, 1.76] | 1 study | Ungraded |
P11-4 + fluoride varnish vs Fluoride varnish (gold standard) 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 -0.71 [-1.13, -0.29] | 5 studies | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Root caries increment · Individuals of all ages · Follow-up ≥1 year, Ritter,2016 [22]; model performance 3 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.48 [0.32, 0.71] | 1 study | Ungraded |
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 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.45 [0.33, 0.61] | 1 study | Ungraded |
Low level laser therapy (LLLT) vs Conventional orthodontic appliance treatment Duration of orthodontic treatment during alignment stage · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment · Alignment stage Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | MD -48.87 [-56.48, -41.26] | 3 studies · 92 participants | Very low |
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) Correlation between vitamin D levels in serum and the risk of dental caries in children: a systematic review… (2023) | RR 1.22 [1.18, 1.25] | 13 studies · 19205 participants | Ungraded |
Upper clear plastic retainer + lower fixed canine-to-canine retainer vs Positioner Stability: Little's Irregularity Index (lower arch) · People who had received fixed appliance orthodontic treatment · 2 years, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | MD -1.00 [-1.65, -0.35] | 1 study · 46 participants | Ungraded |
Botulinum toxin (BoNT) injection into salivary glands vs Placebo injection Drooling Severity and Frequency Scale (DSFS) score · Adults with Parkinson's disease and sialorrhea (drooling) · Approximately 1 month post-injection (one study ~1 week), BoNT type A The effectiveness and safety of botulinum toxin injections for the treatment of sialorrhea with Parkinson's… (2023) | SMD -0.80 [-1.25, -0.36] | 4 studies · 88 participants | 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, Resin permanent cement Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 3.37 [1.90, 5.23] | 738 participants | 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 3 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.60 [0.49, 0.74] | 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, Eugenol-based temporary cement Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 3.34 [1.66, 5.58] | 7043 participants | Ungraded |
Pulp-involved caries vs No pulp-involved caries Body mass index-for-age z score · Children aged 1–6 years · Pulp-involved caries The bi-directional relationship between growth stunting and early childhood caries: a rapid review. (2023) | MD 1.18 | 1 study · 593 participants | 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 with permanent dentition (>12 years) · Permanent dentition Correlation between vitamin D levels in serum and the risk of dental caries in children: a systematic review… (2023) | RR 1.28 [1.21, 1.35] | 2 studies | Ungraded |
Indirect restorations (crowns, fixed partial dentures, inlays/onlays/veneers) vs None (single-group incidence) Pulp necrosis · Vital teeth restored with indirect restorations · ≤5 years, Follow-up ≤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 | Ungraded |
Malocclusion vs No malocclusion Poor oral health-related quality of life · Indians Impact of oral conditions on oral health-related quality of life among Indians- a systematic review and… (2023) | OR 5.44 [1.61, 18.39] | 6 studies · 3720 participants | Very low |
Full-time wear of removable retainer (any type) vs Part-time wear of removable retainer (any type) Survival of retainers · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | Not measured | 0 studies | No studies |
Tooth location Pulp necrosis incidence · Vital teeth · Cheung et al. 2005 maxillary anterior Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 30.2 | 1 study | Ungraded |
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 |
Calcium hydroxide (CH) vs Mineral trioxide aggregate (MTA) Clinical and radiographic success (composite) · Patients with carious pulp exposure in permanent teeth of mixed/unspecified root maturation · ≥6 months; follow-up range 1-2 years, Root maturation: mixed Comparative efficacy of materials used in patients undergoing pulpotomy or direct pulp capping in carious… (2023) | OR 1.11 [0.17, 7.11] | 3 studies · 257 participants | Very low |
Resin sealant (one-time) vs Control (water) New coronal caries in permanent molars (caries prevention) · Children with dental caries in permanent (first) molars · 24 months, Liu 2012 (resin sealant, fissure site) A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent… (2023) | Prevented Fraction 65 | 1 study · 501 participants | 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 with deciduous dentition (<6 years) · Deciduous dentition Correlation between vitamin D levels in serum and the risk of dental caries in children: a systematic review… (2023) | RR 1.68 [1.57, 1.79] | 6 studies | Ungraded |
Mutans streptococci present in oral samples at baseline vs Mutans streptococci absent in oral samples at baseline Development of any (cavitated or non-cavitated) carious lesion · Children younger than 6 years with caries-free primary dentition (no cavitated or non-cavitated lesions at baseline) · 2 years, Follow-up: 2 years Is Mutans Streptococci count a risk predictor of Early Childhood Caries? A systematic review and… (2023) | OR 2.53 [1.22, 5.23] | 4 studies · 297 participants | Ungraded |
Biodentine vs Mineral trioxide aggregate (MTA) Tooth discoloration · Patients with carious pulp exposure in permanent teeth undergoing DPC or pulpotomy · ≥6 months follow-up Comparative efficacy of materials used in patients undergoing pulpotomy or direct pulp capping in carious… (2023) | Tooth discoloration was recorded in 4 trials; the 3 Biodentine-vs-MTA trials consistently showed more discoloration with MTA (Awawdeh 2018: 27/35 MTA vs 0/34 BD; Parinyaprom 2018: 11/31 MTA vs 0/29 BD; Uesrichai 2019:… | 3 studies | Ungraded |
Fluoride mouthwash (e.g., NaF / amine fluoride) vs Blank control (no mouthwash; before-after comparison) Gingival inflammation-related index · 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) | MGI' and BI' was significantly reduced compared to baseline [34]. BOP and GI was slightly lower compared to blank control [46]. | 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 |
Resin infiltration vs CPP-ACP 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 -0.77 [-1.31, -0.23] | 1 study | Ungraded |
Full-time wear of removable retainer (any type) vs Part-time wear of removable retainer (any type) Adverse effects on oral health · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | Not measured | 0 studies | No studies |
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− 0.80 [0.71, 0.89] | 1 study | Ungraded |
Periodontal disease (severe periodontitis) vs Absence of periodontal disease Oral health-related quality of life (OHRQoL) · Adolescents (10-19 years) Oral-health-related quality of life in adolescents: umbrella review. (2023) | individuals with severe periodontitis had worse OHRQoL scores [9]. | NR | 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 12 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.14 [0.08, 0.26] | 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 8 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.44 [0.35, 0.56] | 1 study | Ungraded |
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 |
Light vibrational forces (LVF) vs Conventional orthodontic appliance treatment (placebo or no adjunct) Harms and side effects: orthodontically-induced inflammatory root resorption (OIIRR), mm · Adolescents and adults with malocclusion undergoing orthodontic treatment with fixed or removable appliances Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | MD 0.09 [-0.35, 0.53] | 1 study · 50 participants | Low |
Periodontal disease assessed by Community Periodontal Index (CPI) vs Individuals without periodontal disease (by CPI) Oral health-related quality of life (dichotomous: poor vs not) · Indian adults and elderly (general, police, teachers, institutionalised) Impact of oral conditions on oral health-related quality of life among Indians- a systematic review and… (2023) | Periodontal disease (CPI) vs none: studies show inconsistency; two studies showed poor QoL (Nagarajappa 2015, Saxena 2018), one no significant association (Shivakumar 2018); 1345 participants, 3 observational studies;… | 3 studies · 1345 participants | Very low |
Supraomohyoid neck dissection vs Modified radical neck dissection Locoregional recurrence · Adults with oral cavity or oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Locoregional recurrence: reported but not usable (variable follow-up) (Guo 2014). | 1 study | Ungraded |