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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 |
|---|---|---|---|
Probiotic mouthwash (e.g., Lactobacillus-based) vs Blank control (no mouthwash; before-after comparison) Cariogenic bacteria (Mutans streptococci colony count) · 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) | Colony count of MS was significantly reduced compared to blank control [53]. Colony count of MS was insignificantly increased compared to baseline [33]. | 2 studies | Very low |
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) · 3.5 years (42 months), Follow-up: 3.5 years (42 months) Is Mutans Streptococci count a risk predictor of Early Childhood Caries? A systematic review and… (2023) | OR 4.23 [2.49, 7.18] | 1 study · 366 participants | Ungraded |
Treatment of traumatic dental injury vs Untreated dental trauma Oral health-related quality of life (OHRQoL) · Adolescents (10-19 years) Oral-health-related quality of life in adolescents: umbrella review. (2023) | Treatment of TDI reduces the negative impact on OHRQoL in adolescents, based on parental perception [33]. Treatment of traumatic dental injuries reduces the impact on the OHRQoL with low evidence [46]. | NR | 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− 0.60 [0.47, 0.76] | 1 study | Ungraded |
Fluoride mouthwash vs Blank control Plaque-related index · Orthodontic patients · ≤ 3 months The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | TI was significantly reduced compared to baseline [34]; PI was significantly reduced compared to baseline but similar to blank control [46]. | 2 studies | Very low |
Daily chewing gum for 2 weeks or longer vs No gum chewing or control Unstimulated whole salivary flow rate · Elderly people and medically compromised people with xerostomia · 2 to 12 weeks, Meta-regression by chewing duration The effect of gum chewing on xerostomia and salivary flow rate in elderly and medically compromised… (2023) | SMD per week 0.06 | 6 studies · 291 participants | Ungraded |
Functional edentulism vs No functional edentulism 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 extracted | 2 studies · 368 participants | Very low |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Dolic,2020 [28]; model performance 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.67 [0.45, 0.98] | 1 study | Ungraded |
Light vibrational forces (LVF) vs Conventional orthodontic appliance treatment (placebo or no adjunct) Orthodontic tooth movement (OTM) during alignment stage (reduction in Little's Irregularity Index, mm) · Adolescents and adults with malocclusion undergoing orthodontic treatment with fixed or removable appliances · Full alignment stage (also 4-6 weeks; 10-16 weeks) Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | MD -0.20 [-7.02, 6.62] | 1 study · 54 participants | Low |
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, Follow-up: 6 months Is Mutans Streptococci count a risk predictor of Early Childhood Caries? A systematic review and… (2023) | OR 4.65 [2.01, 10.76] | 2 studies · 303 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 3 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.37 [0.23, 0.59] | 1 study | Ungraded |
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, no 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) 0.06 | 1 study · 1016 participants | Ungraded |
Ceramic restoration material vs Porcelain-fused-to-metal restoration material Pulp necrosis incidence · Vital teeth · Ceramic Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 5.59 [2.89, 9.12] | 460 participants | Ungraded |
Pulp-status assessment method Pulp necrosis incidence · Vital teeth · Radiographic Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 4.95 [2.43, 8.29] | 5 studies · 1853 participants | Ungraded |
Fluoride varnish vs Control (placebo / no active therapy) 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 -0.25 [-0.51, 0.02] | 12 studies | 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) · 3 months, Follow-up: 3 months White spot lesions, plaque accumulation and salivary caries-associated bacteria in clear aligners compared… (2023) | SMD -1.08 [-1.93, -0.24] | 5 studies · 211 participants | Ungraded |
Uncomplicated traumatic dental injury vs No traumatic dental injury 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 11 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.85 [1.29, 2.65] | 1 study | Ungraded |
Indirect restorations vs Follow-up duration Periapical pathosis incidence · Vital teeth · > 5–10 years, > 5–10 years Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 3.88 [1.95, 6.45] | 1864 participants | Ungraded |
Female sex vs Male sex 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 |
Light vibrational forces (LVF) vs Conventional orthodontic appliance treatment (placebo or no adjunct) Harms: non-serious adverse effects (headache, discomfort, loosening of temporary anchorage devices) · 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 | RR 0.96 [0.32, 2.85] | 1 study · 45 participants | Ungraded |
Chlorhexidine (CHX) mouthwash (adjunct to mechanical cleaning) vs Placebo mouthwash 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 -0.45 [-0.70, -0.20] | 3 studies · 98 participants | Low |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Christian,2020 [27]; model performance 2 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.09 [0.90, 1.33] | 1 study | Ungraded |
Functional edentulism (<20 remaining teeth) vs Individuals without functional edentulism Oral health-related quality of life (dichotomous: poor vs not) · Indian elderly (>60 years) Impact of oral conditions on oral health-related quality of life among Indians- a systematic review and… (2023) | Functional edentulism vs none: studies show inconsistency; one study found a significant association (Pushpanjali 2013), one did not (Shivakumar 2018); 368 participants, 2 observational studies; Very low certainty (Fig… | 2 studies · 368 participants | Very low |
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 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.24 [0.21, 0.29] | 1 study | Ungraded |
Multivariable caries prediction model vs Additional prediction model(s) Coronal caries increment · Individuals of all ages · Follow-up ≥1 year, Demers,1992 [14]; model performance 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.60 [1.40, 1.83] | 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 9 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.55 [1.13, 2.13] | 1 study | 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) Barriers and facilitators to implementation of the integration strategy (qualitative) · 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) | The most commonly studied qualitative outcomes were barriers and facilitators related to the strategy implementation process. Reported barriers were time and staff constraints, resource limitations and lack of… | 15 studies | Ungraded |
Dental caries vs Caries-free CA VI concentration · Participants with dental caries and caries-free participants Associations of the activity and concentration of carbonic anhydrase VI with susceptibility to dental… (2023) | SMD -0.66 [-1.00, -0.32] | 2 studies · 141 participants | Ungraded |
Zinc polycarboxylate permanent cement Pulp necrosis incidence · Vital teeth · Zinc polycarboxylate Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 1.1 | 1 study | Ungraded |
Self-assembling peptide P11-4 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 -0.31 [-0.71, 0.09] | 5 studies | 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 mixed dentition (6 to 12 years) · Mixed dentition Correlation between vitamin D levels in serum and the risk of dental caries in children: a systematic review… (2023) | RR 1.08 [1.04, 1.12] | 4 studies | Ungraded |
Self-assembling peptide P11-4 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 -0.38 [-0.87, 0.11] | NR | Ungraded |
Botulinum toxin (BoNT) injection into salivary glands vs Placebo injection Adverse events (participants with >=1 adverse event) · Adults with Parkinson's disease and sialorrhea (drooling) · Approximately 1 month post-injection (one study ~1 week) The effectiveness and safety of botulinum toxin injections for the treatment of sialorrhea with Parkinson's… (2023) | RD 0.15 [0.05, 0.24] | 10 studies · 249 participants | Low |
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, Microbiological assessment: semi-quantitative (Dentocult/commercial kit) Is Mutans Streptococci count a risk predictor of Early Childhood Caries? A systematic review and… (2023) | OR 4.36 [3.53, 5.39] | 6 studies · 2278 participants | Ungraded |
Indirect restorations (crowns, fixed partial dentures, inlays/onlays/veneers) vs None (single-group incidence) Periapical pathosis · Vital teeth restored with indirect restorations · Follow-up ≤5 to >10 years Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 3.63 [2.05, 5.63] | 15 studies · 5376 participants | Low |
Periodontal disease assessed by loss of attachment (LOA / clinical attachment loss) vs Individuals without periodontal disease (by LOA) Oral health-related quality of life (continuous), measured by GOHAI · Indian adults and elderly (police, teachers, general and institutionalised populations) Impact of oral conditions on oral health-related quality of life among Indians- a systematic review and… (2023) | Periodontal disease (LOA) and QoL (continuous, GOHAI): one study reported a significant negative impact (Rekhi 2016), one found no significant association (Marya 2020). Not pooled. | 2 studies | 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+ 4.81 [3.64, 6.35] | 1 study | Ungraded |
Strategies integrating oral health into primary care Dental caries estimates · People receiving or providing primary care; all ages, ability types, and locations Strategies to integrate oral health into primary care: a systematic review. (2023) | 6 of 7 studies reported improved dental caries outcomes; 1 (Vichayanrat 2012) reported no change | 7 studies | 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) · Maximum reported time-point per study (range 1-18 months) White spot lesions, plaque accumulation and salivary caries-associated bacteria in clear aligners compared… (2023) | SMD -1.58 [-2.57, -0.58] | 8 studies · 357 participants | Ungraded |
Fibre-reinforced composite fixed (bonded) retainer vs Multistrand / spiral wire 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 -0.70 [-1.17, -0.23] | 1 study · 52 participants | 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 7 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.87 [1.49, 2.35] | 1 study | Ungraded |
Outer carious dentin (by lesion depth/location) vs Inner carious dentin MMP-9 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-9 expression in different locations and lesion depth, as studies showed opposite effect directions. | 3 studies | Very low |
CAD/CAM nitinol fixed (bonded) retainer vs Conventional/analogue multistrand 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 -0.46 [-0.72, -0.21] | 1 study · 66 participants | Very low |
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 11 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR− 0.54 [0.38, 0.77] | 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 6 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.97 [1.33, 2.90] | 1 study | Ungraded |
Functional edentulism (<20 remaining teeth) vs Individuals without functional edentulism Oral health-related quality of life (continuous), measured by GOHAI · Indian elderly (>60 years) Impact of oral conditions on oral health-related quality of life among Indians- a systematic review and… (2023) | SMD 0.31 [-0.37, 0.99] | 4 studies · 1146 participants | Very low |
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, Subjective pulp-status assessment Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations:… (2023) | Proportion 3.91 [1.86, 6.66] | 3181 participants | Ungraded |
CPP-ACP 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 0.25 [-0.24, 0.73] | 2 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 1 Multivariable prediction models of caries increment: a systematic review and critical appraisal. (2023) | LR+ 1.88 [1.38, 2.55] | 1 study | Ungraded |