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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 |
|---|---|---|---|
Calcium hydroxide (CH) vs Mineral trioxide aggregate (MTA) Clinical and radiographic success (composite) · Patients with carious pulp exposure in mature permanent teeth · ≥6 months; follow-up range 1-3 years, Root maturation: mature Comparative efficacy of materials used in patients undergoing pulpotomy or direct pulp capping in carious… (2023) | OR 3.34 [1.81, 6.17] | 5 studies · 537 participants | Moderate |
Indirect restorations (crowns, fixed partial dentures, inlays/onlays/veneers) vs None (single-group incidence) Periapical pathosis · Vital teeth restored with indirect restorations · >10 years, Follow-up >10 years Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 4.05 [0.89, 9.36] | 2656 participants | Ungraded |
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 0.18 [-0.29, 0.64] | 1 study | Ungraded |
Light vibrational forces (LVF) vs Conventional orthodontic appliance treatment (placebo or no adjunct) Oral health-related quality of life (OHRQoL) · 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 | Katchooi 2018 (unclear risk of bias): light vibrational forces had no statistically significant (P>0.05) effect on OHRQoL when used with orthodontic aligners. | 1 study · 27 participants | Ungraded |
Mineral trioxide aggregate (MTA) vs Calcium hydroxide (CH) Clinical and radiographic success · Patients with carious pulp exposure in permanent teeth undergoing direct pulp capping · 1 to 3 years, Direct pulp capping Comparative efficacy of materials used in patients undergoing pulpotomy or direct pulp capping in carious… (2023) | OR 3.10 [1.66, 5.79] | 4 studies · 559 participants | Moderate |
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− 0.55 [0.48, 0.63] | 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 9 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 2.00 [1.35, 2.95] | 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, 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 participants | Ungraded |
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 studies | No 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 participants | Ungraded |
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 study | Ungraded |
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 studies | Very 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 study | Ungraded |
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 60 | 1 study · 501 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 15 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.58 [1.09, 2.30] | 1 study | Ungraded |
Upper clear plastic retainer + lower interproximal reduction (adjunctive) 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 -0.70 [-1.37, -0.03] | 1 study · 45 participants | Ungraded |
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 64 | 1 study · 306 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 16 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.60 [0.43, 0.83] | 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, 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 participants | Ungraded |
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 participants | Moderate |
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. | NR | Ungraded |
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 participants | Moderate |
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 participants | Very 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 study | Ungraded |
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 study | Ungraded |
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 studies | Ungraded |
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 studies | Very 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 study | Ungraded |
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 participants | Very low |
CAD/CAM nitinol fixed (bonded) retainer vs Conventional/analogue multistrand fixed (bonded) retainer Adverse effects on oral health: bleeding on probing (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 RCTs at 12-month follow-up; 2 RCTs at 6 months found no difference (low-certainty) | 0 studies | No studies |
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 studies | Ungraded |
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 0.3 | 1 study · 452 participants | Ungraded |
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 extracted | 1 study | 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 8 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.97 [1.73, 2.25] | 1 study | Ungraded |
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]. | NR | Ungraded |
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 extracted | NR | 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 5 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.69 [1.17, 2.44] | 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, tooth level) A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent… (2023) | Prevented Fraction 41 | 1 study · 501 participants | Ungraded |
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 studies | No 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 study | Ungraded |
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 participants | Low |
Light-emitting diode (LED) photobiomodulation vs Conventional orthodontic appliance treatment Total number of orthodontic appliance adjustment appointments during treatment · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | Total number of orthodontic appliance adjustment appointments required during treatment stage | Not reported | NR | 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, 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 participants | Ungraded |
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 extracted | NR | 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− 0.47 [0.33, 0.66] | 1 study | Ungraded |
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 studies | Very 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 studies | Ungraded |
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] | NR | Ungraded |
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 studies | No 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 study | Ungraded |