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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.

Limit to evidence status or GRADE (optional)

5,762 questions in 263 reviews · Dental caries

current versions
No 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.

QuestionEffectEvidenceStatus / GRADE
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, Zinc phosphate permanent cement
Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023)
Proportion 4.92 [3.85, 6.20]1387 participantsUngraded
Surgery plus adjuvant radiotherapy vs Chemotherapy (chemoradiotherapy)
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: not reported for any participants (Iyer 2015).0 studiesNo studies
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 participantsUngraded
Multivariable caries prediction model vs Additional prediction model(s)
Root caries increment · Individuals of all ages · Follow-up ≥1 year, Hayes,2017 [33]; model performance 2
Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023)
LR+ 2.78 [2.14, 3.62]1 studyUngraded
Outer carious dentin (by lesion depth/location) vs Inner carious dentin
MMP-2 location/depth · Human ex vivo carious dentin
Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023)
The evidence is very uncertain about the MMP-2 location in dentin, as no effect direction was found (MMP-2 ubiquitous and variable across regions).4 studiesVery low
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 4
Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023)
LR+ 1.88 [1.34, 2.64]1 studyUngraded
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, tooth level)
A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent… (2023)
Prevented Fraction 601 study · 501 participantsUngraded
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 15
Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023)
LR+ 1.58 [1.09, 2.30]1 studyUngraded
Sodium fluoride (NaF) varnish, applied every 3 months, plus OHI vs Inactive control (OHI + water)
New root carious lesions (caries prevention) · Older adults with root caries (community-dwelling or residential elders) · 36 months, Tan 2010
A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent… (2023)
Prevented Fraction 641 study · 306 participantsUngraded
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 16
Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023)
LR− 0.60 [0.43, 0.83]1 studyUngraded
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, Polyether impression material
Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023)
Proportion 4.02 [2.47, 5.92]2985 participantsUngraded
Outer carious dentin (by lesion depth/location) vs Inner carious dentin
MMP-20 location/depth (outer vs inner) · Human ex vivo carious dentin
Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023)
MMP-20 probably reduces in carious outer dentin when compared to carious inner dentin (moderate certainty); MMP-20 was significantly lower in outer dentin than inner (Shimada et al., 2009).1 study · 5 participantsModerate
Temporomandibular disorder (TMD) vs No temporomandibular disorder
Oral health-related quality of life (OHRQoL) · Adolescents (10-19 years)
Oral-health-related quality of life in adolescents: umbrella review. (2023)
dental caries, malocclusion [9, 26-30], TMD [9], dental trauma (TDI) [32, 34, 35], poor brushing [36], toothache [26], periodontal disease [34] and edentulism [9] negatively affect the quality of life of adolescents.NRUngraded
Herbal / plant-extract mouthwash (e.g., essential oils, Persica, propolis, Azadirachta indica, chamomile, Aloe vera) vs Blank control (no mouthwash; before-after comparison)
Gingival Index (GI, Loe & Silness 1963) · 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)
WMD -0.20 [-0.32, -0.09]3 studies · 132 participantsModerate
Superselective neck dissection vs Selective neck dissection
Adverse events associated with treatment · 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
Adverse events: no adverse events reported; 72 participants (2 RCTs).2 studies · 72 participantsVery low
Multivariable caries prediction model vs Additional prediction model(s)
Root caries increment · Individuals of all ages · Follow-up ≥1 year, Hayes,2017 [33]; model performance 4
Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023)
LR+ 1.88 [1.53, 2.29]1 studyUngraded
Multivariable caries prediction model vs Additional prediction model(s)
Coronal and/or root caries increment · Individuals of all ages · Follow-up ≥1 year, Powell,1991 [21]; model performance 1
Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023)
LR− 0.20 [0.04, 0.90]1 studyUngraded
Malocclusion (assessed by DAI, IOTN or WHO criteria) vs Individuals without malocclusion
Oral health-related quality of life (continuous), measured by OHIP-14 / ECOHIS / FIS · Indian children, adolescents and adults
Impact of oral conditions on oral health-related quality of life among Indians- a systematic review and… (2023)
Malocclusion and QoL (continuous, OHIP-14/ECOHIS/FIS): malocclusion had a significant negative influence on OHRQoL (Vinayagamoorthy 2020, Mary 2019). Not pooled.2 studiesUngraded
Chlorhexidine mouthwash vs Placebo
Plaque Index · Orthodontic patients · ≤ 3 months
The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023)
Plaque Index was significantly reduced compared to placebos according to two studies [20; 32].2 studiesVery low
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 2
Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023)
LR+ 3.00 [2.57, 3.50]1 studyUngraded
Carious dentin before cavity sealing vs Carious dentin after cavity sealing
MMP-9 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)
There is no difference of MMP-9 expression/activity before and after cavity sealing, although the evidence is very uncertain.2 studies · 48 participantsVery low
Periodontal disease assessed by Community Periodontal Index (CPI) vs Individuals without periodontal disease (by CPI)
Oral health-related quality of life (continuous), measured by GOHAI · 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) and QoL (continuous, GOHAI): CPI scores negatively correlated with QoL in one study (Rekhi 2016); no significant relation in another (Marya 2020, P>0.05). Not pooled.2 studiesUngraded
38% SDF (every 6 months) vs No treatment
Inactive (arrested) carious lesions on permanent first molars · Children with dental caries in permanent (first) molars · 36 months, Llodra 2005
A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent… (2023)
Mean inactive lesions per child 0.31 study · 452 participantsUngraded
Root caries lesion biofilm vs Sound-site supragingival biofilm
Collagen-degrading bacteria · Root caries lesion biofilm
Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex… (2023)
no estimate extracted1 studyUngraded
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 8
Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023)
LR+ 1.97 [1.73, 2.25]1 studyUngraded
Higher parental / maternal education vs Lower parental education
Oral health-related quality of life (OHRQoL) · Adolescents (10-19 years)
Oral-health-related quality of life in adolescents: umbrella review. (2023)
Adolescents from families with higher incomes and higher levels of maternal education have better OHRQoL scores [34]. Children from families with high income, parental education and family economy had better OHRQoL [42].NRUngraded
Temporomandibular disorder vs No temporomandibular disorder
Oral health-related quality of life · Adolescents aged 10-19 years
Oral-health-related quality of life in adolescents: umbrella review. (2023)
no estimate extractedNRUngraded
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 5
Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023)
LR+ 1.69 [1.17, 2.44]1 studyUngraded
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, tooth level)
A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent… (2023)
Prevented Fraction 411 study · 501 participantsUngraded
Superselective neck dissection vs Selective neck dissection
Total mortality · 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
Total mortality: not reported.0 studiesNo studies
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 4
Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023)
LR− 0.36 [0.26, 0.50]1 studyUngraded
Calcium hydroxide (CH) vs Mineral trioxide aggregate (MTA)
Clinical and radiographic success (composite) · Patients with carious pulp exposure in permanent teeth undergoing DPC or pulpotomy (all treatment types and… · ≥6 months; follow-up range 1-3 years, Unadjusted (all CH vs MTA studies)
Comparative efficacy of materials used in patients undergoing pulpotomy or direct pulp capping in carious… (2023)
OR 2.94 [1.93, 4.49]10 studies · 900 participantsLow
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, Ceramic fabrication material
Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023)
Proportion 5.59 [2.89, 9.12]460 participantsUngraded
Irregular brushing vs Regular brushing
Oral health-related quality of life · Adolescents aged 10-19 years
Oral-health-related quality of life in adolescents: umbrella review. (2023)
no estimate extractedNRUngraded
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− 0.47 [0.33, 0.66]1 studyUngraded
Fluoride mouthwash vs Blank control
Cariogenic bacteria (Mutans streptococci) · Orthodontic patients · ≥ 12 months
The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023)
Colony count of MS was similar to blank control according to two studies [37; 59].2 studiesVery low
Clear aligners (CA) vs Conventional fixed orthodontic appliances (CF)
Salivary caries-associated bacteria (S. mutans and Lactobacilli, subjects with >10^5 CFU/mL) · Orthodontic patients undergoing comprehensive treatment (late mixed or permanent dentition, no active caries) · 3 and 6 months
White spot lesions, plaque accumulation and salivary caries-associated bacteria in clear aligners compared… (2023)
Not meta-analyzed (insufficient number of studies). Both included observational studies (Mummolo 2020 [19]; Mummolo 2020 [25]) reported a higher number of subjects with S. mutans and Lactobacilli >10^5 CFU/mL in the…2 studiesUngraded
P11-4 + fluoride varnish 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 -0.54 [-1.15, 0.08]NRUngraded
Supraomohyoid neck dissection vs Modified radical neck dissection
Disease-free survival · Adults with oral cavity or oropharyngeal cancer
Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane
Disease-free survival: not reported (Guo 2014 reported disease-specific survival, not a review outcome).0 studiesNo studies
Multivariable caries prediction model vs Additional prediction model(s)
Root caries increment · Individuals of all ages · Follow-up ≥1 year, Hayes,2017 [33]; model performance 5
Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023)
LR+ 2.13 [1.68, 2.69]1 studyUngraded
Gingivitis vs No gingivitis
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)
no estimate extracted3 studies · 943 participantsVery low
Sentinel node biopsy (neck dissection only if biopsy positive) vs Elective neck dissection
Total 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 1.00 [0.90, 1.11]1 study · 279 participantsLow
Tooth loss or edentulism vs No tooth loss or edentulism
Oral health-related quality of life · Adolescents aged 10-19 years
Oral-health-related quality of life in adolescents: umbrella review. (2023)
no estimate extractedNRUngraded
Malocclusion (occlusal disorders) vs Absence/lower severity of malocclusion
Oral health-related quality of life (OHRQoL) · Adolescents (10-19 years)
Oral-health-related quality of life in adolescents: umbrella review. (2023)
The studies who avaliate occlusal disorders, concluded that this pathology have a negative impact on OHRQoL in adolescents.NRUngraded
Before cavity sealing vs After cavity sealing
MMP-2 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 extracted2 studies · 48 participantsVery low
Dental caries (assessed by DMFT/deft/dmft, WHO criteria or PUFA) vs Individuals without dental caries
Oral health-related quality of life (dichotomous: poor vs not) · Indians across all ages (children, adolescents, adults, elderly) · By OHRQoL scale / score direction (dichotomous)
Impact of oral conditions on oral health-related quality of life among Indians- a systematic review and… (2023)
OR 4.73 [2.91, 7.68]7 studies · 4114 participantsUngraded
Pulp-involved caries vs No pulp-involved caries
Weight-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 1.171 study · 593 participantsUngraded
Resin-modified glass ionomer cement (RMGIC) vs Resin composite (RC)
Secondary caries (occurrence) · Patients requiring dental restoration; deciduous (primary) teeth · 1 year of follow-up, Resin-modified GIC (CIVMR)
Clinical efficacy of bioactive restorative materials in controlling secondary caries: a systematic review… (2023)
RR 1.03 [0.07, 15.81]1 study · 71 participantsUngraded
Root carious dentin vs Coronal carious dentin
MMP-13 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)
MMP-13 may be increased in root caries when compared to coronal, but the evidence is very uncertain; no MMP-13 activity observed in the crown region by western blot (Yeon Lee et al., 2013).1 study · 7 participantsVery low
Pre-operative bone level < 35% vs Pre-operative bone level ≥ 35%
Periapical pathosis incidence · Vital teeth · Bone level ≥ 35%
Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023)
Proportion 01 studyUngraded