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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 |
|---|---|---|---|
Malocclusion vs No malocclusion Impaired OHRQoL measured with CPQ 11-14 (quantitative synthesis / meta-analysis) · Adolescents aged 10-19 years Malocclusions and quality of life among adolescents: a systematic review and meta-analysis. (2023) | Rate/prevalence ratio (RR/PR) 1.15 [1.12, 1.18] | 4 studies · 3672 participants | Moderate |
Calcium-enriched mixture (CEM) vs Mineral trioxide aggregate (MTA) Clinical and radiographic success (composite) · Patients with carious pulp exposure in permanent teeth undergoing pulpotomy · ≥6 months follow-up Comparative efficacy of materials used in patients undergoing pulpotomy or direct pulp capping in carious… (2023) | CEM vs MTA was investigated in 2 RCTs (Asgary 2017; Nosrat 2013) for the primary outcome; not pooled owing to heterogeneity. The per-trial forest plots (Figure 8) indicated MTA performed comparably to CEM. Weak evidence. | 2 studies | Ungraded |
Resin-modified glass ionomer cement (RMGIC) 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 1.82 [0.45, 7.28] | 2 studies · 126 participants | Low |
Malocclusion (assessed by DAI, IOTN or WHO criteria) vs Individuals without malocclusion Oral health-related quality of life (continuous), measured by GOHAI · 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, GOHAI): no significant difference in OHRQoL between individuals with and without malocclusion (Appukuttan 2016). Single study, not pooled. | 1 study | Ungraded |
Bruxism vs Individuals without bruxism (non-bruxers) Oral health-related quality of life (continuous), measured by OHIP-14 · Indian children and adults Impact of oral conditions on oral health-related quality of life among Indians- a systematic review and… (2023) | Bruxism and QoL (continuous, OHIP-14): bruxers have poorer OHRQoL than non-bruxers (Thetakala 2018, Suguna 2020). Two studies, 284 individuals; not pooled. | 2 studies · 284 participants | 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) · 6 months, Follow-up: 6 months White spot lesions, plaque accumulation and salivary caries-associated bacteria in clear aligners compared… (2023) | SMD -2.04 [-3.37, -0.70] | 5 studies · 253 participants | Ungraded |
Chlorhexidine 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 blank control according to one study [53]; one study reported a significant reduction compared to baseline [51]. | 2 studies | Very low |
Atraumatic restorative treatment (ART) sealant (one-time) vs No treatment New coronal caries in permanent first molars (caries prevention) · Children with dental caries in permanent (first) molars · 18 months, Monse 2012 (ART one-time, with brushing programme) A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent… (2023) | Mean new caries increment (surfaces) 0.01 | 1 study · 1016 participants | Ungraded |
Part-time clear plastic (removable) retainer vs Any type of fixed (bonded) 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 0.92 [0.23, 1.61] | 1 study · 56 participants | Very low |
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 2 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 1.00 [0.85, 1.18] | 1 study | Ungraded |
Carious dentin vs Sound dentin MMP-2 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) | MMP-2 may be increased in carious dentin when compared to sound dentin, but the evidence is very uncertain. | 7 studies · 373 participants | Very low |
Toothache vs No toothache 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, Temporization >2 weeks Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 4.25 [1.28, 8.85] | 2280 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 4 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.54 [1.22, 1.94] | 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 · >10 years, Follow-up >10 years Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 6.74 [2.82, 12.18] | 3640 participants | Ungraded |
2.26% ammonium bifluoride (one-time) vs Control (details reported as unavailable) New coronal caries in permanent first molars (caries prevention) · Children with dental caries in permanent (first) molars · 12 months, Mauro 2004 A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent… (2023) | Prevented Fraction 56 | 1 study · 141 participants | Ungraded |
Surgery vs Radiotherapy alone Adverse events associated with treatment · Adults with oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Adverse events: grade 2+ treatment-related events similar (31/34 radiotherapy vs 33/34 surgery; RR 0.94, 0.83 to 1.06); more hearing loss/neutropenia/constipation/tinnitus with radiotherapy, more oral bleeding/trismus… | 1 study · 68 participants | Very low |
Upper clear plastic retainer + lower fixed canine-to-canine retainer vs Upper clear plastic retainer + lower interproximal reduction (adjunctive), no lower retainer 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 -0.30 [-0.73, 0.13] | 1 study · 47 participants | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Angulo,1995 [13]; model performance 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.94 [0.74, 1.20] | 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: saliva Is Mutans Streptococci count a risk predictor of Early Childhood Caries? A systematic review and… (2023) | OR 3.92 [3.20, 4.80] | 9 studies · 2577 participants | Ungraded |
Dental agenesis vs No dental agenesis 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 |
Growth stunting (linear growth retardation, low height-for-age) vs Children without growth stunting (normal height-for-age) Early childhood caries (def-t/dmft caries experience) · Children in early childhood (0-6 years) · Folayan et al. 2019 (Nigeria; adjusted, model 3) The bi-directional relationship between growth stunting and early childhood caries: a rapid review. (2023) | APR 0.14 [0.03, 0.69] | 1 study · 370 participants | Ungraded |
Traumatic dental injury (dental trauma) vs No dental trauma Oral health-related quality of life (OHRQoL) · Adolescents (10-19 years) Oral-health-related quality of life in adolescents: umbrella review. (2023) | The impact of dental trauma sequelae on OHRQoL in adolescents was observed in five systematic reviews [31-35]. The studies show that uncomplicated traumatic injuries do not have a negative impact on the OHRQoL of… | 5 studies | Ungraded |
Carious dentin vs Sound dentin MMP-2 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 | 7 studies · 373 participants | Very low |
Resin composite (RC) 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 3.05 [0.95, 9.79] | 6 studies · 479 participants | Low |
Surgery plus radiotherapy vs Radiotherapy alone 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 0.24 [0.10, 0.59] | 1 study · 35 participants | Very low |
Herbal mouthwash vs Placebo Plaque-related index · Orthodontic patients · ≤ 3 months The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | PI was significantly reduced compared to placebo [56]; VPI was significantly reduced compared to placebo [41]; PI was insignificantly reduced compared to placebo [19]. | 3 studies | Low |
Carious dentin vs Sound dentin MMP-9 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 | 3 studies | 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 4 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.48 [0.39, 0.58] | 1 study | Ungraded |
Fluoride 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 according to two studies [33; 34]. | 2 studies | Very low |
Chlorhexidine (CHX) mouthwash (adjunct to mechanical cleaning) vs Placebo mouthwash Pocket probing depth (PD) · 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) | PD was significantly reduced except mid-lingual site compared to placebo [32]. The changes of PD were significantly higher compared to placebo [56]. | 2 studies | Low |
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 2 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.79 [0.69, 0.89] | 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 2 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.44 [0.37, 0.51] | 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 2 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 2.11 [1.82, 2.45] | 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 2 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.00 [0.73, 1.38] | 1 study | Ungraded |
Growth stunting (linear growth retardation, low height-for-age) vs Children without growth stunting (normal height-for-age) Early childhood caries (def-t/dmft caries experience) · Children in early childhood (0-6 years) · Vieira et al. 2020 (Brazil) The bi-directional relationship between growth stunting and early childhood caries: a rapid review. (2023) | Correlation (r) -0.091 | 1 study · 82 participants | Ungraded |
Clear aligners (CA) vs Conventional fixed orthodontic appliances (CF) Incidence of white spot lesions (WSLs) · Orthodontic patients undergoing comprehensive treatment (late mixed or permanent dentition, no active caries) · End of orthodontic treatment (varying) White spot lesions, plaque accumulation and salivary caries-associated bacteria in clear aligners compared… (2023) | Not meta-analyzed (heterogeneous methods; tooth-based vs patient-based incidence). 4 studies assessed WSL incidence; 3 (Albhaisi 2020 [12]; Buschang 2019 [29]; Dallel 2020 [30]) reported a lower risk of developing WSLs… | 4 studies | Ungraded |
Malocclusion vs No malocclusion 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, Gao.2010 [17]; model performance 4 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.18 [0.16, 0.22] | 1 study | Ungraded |
Severe periodontitis vs No or less severe periodontal disease 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, Temporization ≤2 weeks Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 1.47 [0.81, 2.31] | 1907 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− 0.66 [0.49, 0.90] | 1 study | Ungraded |
Intervention NR Oral health practices Strategies to integrate oral health into primary care: a systematic review. (2023) | 2 of 2 studies reported favourable outcomes | 2 studies | Ungraded |
Tooth location Pulp necrosis incidence · Vital teeth · Cheung et al. 2005 mandibular anterior Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 0 | 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 2 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.33 [0.24, 0.44] | 1 study | Ungraded |
Pre-operative caries fillings or crowns vs Intact teeth Pulp necrosis incidence · Vital teeth · Pre-operative caries fillings or crowns Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 13 | 1 study | 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 3 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.61 [0.42, 0.88] | 1 study | Ungraded |
Light vibrational forces (LVF) vs Conventional orthodontic appliance treatment (placebo or no adjunct) Cost of treatment · 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 | Cost of treatment was not investigated in any of the included studies. | NR | No studies |
Carious dentin vs Sound dentin MMP-9 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) | MMP-9 may be increased in carious dentin when compared to sound dentin, but the evidence is very uncertain. | 3 studies · 292 participants | Very low |
Hawley removable retainer vs Clear plastic removable retainer 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 |