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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 |
|---|---|---|---|
T allele vs C allele Dental caries · Children (<18 years) with vs without dental caries · Allelic model (T vs C), Caucasian ethnicity Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.00 [0.72, 1.39] | NR | Ungraded |
Er:YAG laser irradiation of sound enamel before acid challenge vs No anticaries intervention (untreated enamel) Calcium ions released in acidic solution · Human tooth enamel specimens, sound/intact (in vitro) · After acid immersion (acid dissolution) Effect of Er:YAG Laser Irradiation on Preventing Enamel Caries: A Systematic Review and Meta-Analysis. (2024) | SMD -0.40 [-0.96, 0.15] | 6 studies · 292 participants | Ungraded |
Original development of CAMBRA (Caries Management by Risk Assessment) or CAT (Caries-risk Assessment Tool) multivariable models vs Not applicable Model development with reported performance measures (per CHARMS) · Individuals of any age at risk of caries increment · Model development studies Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | no estimate extracted | 0 studies | No studies |
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, Treated by prosthodontists Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 1.87 [0.84, 3.31] | 3834 participants | Ungraded |
Resin infiltration 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 -0.52 [-1.16, 0.12] | NR | Ungraded |
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) Access to oral healthcare (referral pathways, documentation processes, operating efficiencies, staffing, visits for oral health issues, uptake of fluoride varnish/other preventive treatment, and visits to an oral health professional) · 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) | Access to oral healthcare was the primary outcome most studied (n=19). Most studies reported results favouring the integration strategy, including improvements in referral pathways, documentation processes, operating… | 19 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) · 6 months to 3.5 years, Overall Is Mutans Streptococci count a risk predictor of Early Childhood Caries? A systematic review and… (2023) | OR 4.13 [3.33, 5.12] | 12 studies · 3010 participants | Moderate |
P11-4 + fluoride varnish 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 -0.78 [-1.33, -0.24] | 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 2 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.31 [0.24, 0.40] | 1 study | Ungraded |
ACTIVA bioactive restorative material vs Glass ionomer cement (GIC) 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 22.80 [0.89, 584.17] | 1 study · 153 participants | Very low |
Tooth location Pulp necrosis incidence · Vital teeth · Kontakiotis et al. 2015 mandibular posterior Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 7.1 | 1 study | 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) · 6 months to 3.5 years, Sample: plaque Is Mutans Streptococci count a risk predictor of Early Childhood Caries? A systematic review and… (2023) | OR 5.16 [2.99, 8.91] | 5 studies · 736 participants | Ungraded |
Edentulism (complete or partial missing teeth) vs Individuals without edentulism Oral health-related quality of life (dichotomous: poor vs not) · Indian elderly Impact of oral conditions on oral health-related quality of life among Indians- a systematic review and… (2023) | Edentulism and QoL (dichotomous): edentulism did not affect OHRQoL (Shivakumar 2018). Single study, not pooled. | 1 study | Ungraded |
Full-time wear of removable retainer (any type) vs Part-time wear of removable retainer (any type) Patient satisfaction · 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, Hänsel Petersson,2002 [18]; model performance 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.74 [0.63, 0.87] | 1 study | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Campus,2012 [26]; model performance 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 5.53 [4.36, 7.03] | 1 study | Ungraded |
Safe housing / favorable household conditions vs Unsafe housing / poor household conditions Oral health-related quality of life (OHRQoL) · Adolescents (10-19 years) Oral-health-related quality of life in adolescents: umbrella review. (2023) | having parents who can provide dental care and safe housing are positive predictors for OHRQoL. Socioeconomic factors related to the area of residence, satisfaction with oral health and dental care were shown to be… | NR | 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) · Range 1 to 18 months (maximum time-point per study), Study design: randomized controlled trials White spot lesions, plaque accumulation and salivary caries-associated bacteria in clear aligners compared… (2023) | SMD -1.79 [-3.63, 0.04] | 3 studies · 111 participants | Moderate |
Intervention NR Quality of life Strategies to integrate oral health into primary care: a systematic review. (2023) | 1 study reported an unfavourable outcome | 1 study | 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 |
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 5 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.22 [0.19, 0.22] | 1 study | Ungraded |
Resin infiltration 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 -0.70 [-1.18, -0.21] | 4 studies | Ungraded |
Mineral trioxide aggregate (MTA) vs Calcium hydroxide (CH) Clinical and radiographic success · Patients with carious pulp exposure in permanent teeth undergoing pulpotomy · 1 to 2 years, Full or partial pulpotomy Comparative efficacy of materials used in patients undergoing pulpotomy or direct pulp capping in carious… (2023) | OR 2.36 [0.47, 11.75] | 6 studies · 341 participants | Low |
Surgery plus adjuvant radiotherapy vs Chemotherapy (chemoradiotherapy) Disease-free survival · Adults with oral cavity or oropharyngeal cancer · oral cavity Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Disease-free survival: not reported (Iyer 2015). | 0 studies | No studies |
Part-time clear plastic (removable) retainer vs Any type of fixed (bonded) retainer Adverse effects on oral health: Gingival 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 -0.34 [-0.66, -0.02] | 1 study · 59 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 10 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.26 [0.18, 0.37] | 1 study | 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 |
38% SDF (indirect pulp capping) vs Resin-modified GIC (RMGIC) Restoration color, marginal staining and luster (esthetics) · Children with deep occlusal caries in young permanent first molars (indirect pulp capping) · 12 months, Baraka 2022 A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent… (2023) | Baraka et al. (2022): significant differences in restoration color, marginal staining and luster favoring RMGIC over both SDF groups (p=0.03); SDF caused black staining that darkened over time. | 1 study · 49 participants | Ungraded |
Fibre-reinforced composite fixed (bonded) retainer vs Multistrand / spiral wire fixed (bonded) retainer Patient satisfaction: aesthetics (VAS 0-10 cm, 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 1.49 [0.76, 2.22] | 1 study · 32 participants | Very 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 3 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.82 [0.77, 0.88] | 1 study | 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 root caries increment (negative likelihood ratio, LR-) · Older adults (aged 52-95; mean 52-73) at risk of root caries increment · 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. Hayes 2017 [33] (5 Cariogram root-caries models): per-model LR- (Table 2) ranged 0.34-0.41; none reached the useful rule-out threshold of <=0.20. | 1 study | Ungraded |
Surgery plus radiotherapy vs Radiotherapy alone 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: not reported. | 0 studies | No studies |
Platelet-rich fibrin (PRF) vs Mineral trioxide aggregate (MTA) Clinical and radiographic success (composite) · Patients with carious pulp exposure in immature permanent teeth undergoing pulpotomy · ≥6 months follow-up Comparative efficacy of materials used in patients undergoing pulpotomy or direct pulp capping in carious… (2023) | PRF vs MTA was investigated in 2 RCTs (Alawwad 2020; Keswani 2014) for the primary outcome; the two trials provided contradictory evidence and differed in risk of bias, so were not pooled. Weak evidence. | 2 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 4 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.34 [0.28, 0.40] | 1 study | Ungraded |
38% SDF vs Atraumatic restorative treatment (ART) Caries/restoration status in permanent molars · Children with dental caries in permanent (first) molars · 9 months, Satyarup 2022 (school setting, India) A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent… (2023) | Satyarup et al. (2022): 38% SDF vs ART; SDF group 5.6% carious teeth with partly lost restorations vs ART 16.7% carious with partly lost and 8.9% carious with completely lost restorations (p=0.004, favoring SDF). | 1 study · 190 participants | Ungraded |
38% SDF plus oral health instruction vs oral health instruction plus tonic water new root-surface carious lesions or restorations · community-dwelling older adults with root caries · 30 months A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent… (2023) | Preventative fraction (%) 62 | 1 study · 323 participants | Ungraded |
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 |
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 2 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.55 [0.38, 0.82] | 1 study | Ungraded |
Sodium fluoride (5% NaF, one-time [Mauro] or every 6 months [Liu]) vs Control (water or unspecified) New coronal caries in permanent molars (caries prevention) · Children with dental caries in permanent (first) molars · 24 months, Liu 2012 (5% NaF, fissure site) A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent… (2023) | Prevented Fraction 48 | 1 study · 501 participants | Ungraded |
CAD/CAM nitinol fixed (bonded) retainer vs Conventional/analogue multistrand fixed (bonded) retainer Patient satisfaction: discomfort/pain (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 | No studies measured or reported this outcome | 0 studies | No studies |
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, PFM fabrication material Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 5.71 [0.12, 18.75] | 1980 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 |
Indirect restorations (crowns, fixed partial dentures, inlays/onlays/veneers) vs None (single-group incidence) Pulp necrosis · Vital teeth restored with indirect restorations · >5-10 years, Follow-up >5-10 years Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 5.53 [3.74, 7.64] | 2443 participants | Ungraded |
38% SDF plus potassium iodide and oral health instruction vs oral health instruction plus tonic water new root-surface carious lesions or restorations · community-dwelling older adults with root caries · 30 months A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent… (2023) | Preventative fraction (%) 52 | 1 study · 323 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 5 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.36 [0.26, 0.50] | 1 study | 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+ 3.88 [3.19, 4.71] | 1 study | Ungraded |
Indirect restoration placement by undergraduate students vs None Pulp necrosis incidence · Vital teeth · Undergraduate students Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 5.68 [3.17, 8.86] | 1604 participants | Ungraded |
Chlorhexidine mouthwash vs Placebo 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 placebos according to three studies [34; 48; 52]; colony count of MS was slightly reduced compared to placebo in a short time in one study [40]. | 4 studies | Very low |
Resin infiltration vs P11-4 + fluoride varnish 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 0.01 [-0.62, 0.65] | NR | Ungraded |
Cariogram multivariable caries-risk model (including modified/reduced-predictor versions) vs Alternative prediction model(s) within the same study, or no formal comparator (models compared descriptively; no between-model statistical test) Predictive performance of the Cariogram for caries increment (positive likelihood ratio, LR+) · Children/adolescents (coronal caries) and older adults (root caries); populations from areas with varying caries risk · 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) | Six validation studies (5 coronal, 1 root) evaluated modified Cariogram models (not the original model per se). Review-stated LR+ range 1.1-3.8 (with one exception). LR+ was not substantially changed by excluding the… | 6 studies | Ungraded |