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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 |
|---|---|---|---|
Oral cancer patients (cases) vs Healthy controls Periodontal parameters (all measures pooled) in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, Overall (all periodontal measures pooled) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 0.95 [0.41, 1.49] | 5 studies | Ungraded |
Non-syndromic cleft lip and palate (CLP) status and its oral microbiota (exposure/grouping) vs Children and adolescents aged 0-18 years without CLP (controls) Streptococcus mutans salivary/plaque counts (cariogenic microbiota) · Children and adolescents aged 0-18 years with non-syndromic cleft lip and palate (CLP) Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | Two studies were analyzed that reported the outcome in means of the presence of Streptococcus mutans, and that there was no difference between the means for healthy patients and those with CLP. The results of these… | 2 studies | Ungraded |
Surgically-anchored orthodontic treatment (miniplates) vs Untreated control (no treatment) Overjet · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 7.69 [6.99, 8.40] | 1 study · 30 participants | Low |
Consumption of xylitol chewing gum by women (mothers) vs Consumption of CHX/xylitol gum by women, or CHX varnish applied to women's dentition Child microbiological presence (any mutans streptococci colonisation) · For interventions, pregnant women and mothers of infants in the first year of life; for outcomes, children up to 6… Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | RR 0.60 [0.45, 0.81] | 2 studies | Ungraded |
Facemask vs Untreated control (no treatment) Overjet · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment (9 to 15 months) Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 5.04 [4.29, 5.80] | 2 studies · 92 participants | Ungraded |
Silver diamine fluoride (topical application) vs Control (placebo/no treatment or other topical fluoride agents) Prevention of new caries (caries development/increment) · Preschool children (primary dentition) at risk of new caries · 6 to 18 months The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024) | Narrative (2 RCTs; not meta-analyzed): Zheng 2023 reported mean decayed surfaces (ds) reduced from 0.7+/-1.9 to 0.4+/-1.5; Sirivichayakul 2023 reported a caries development rate of 27.2%. | 2 studies | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Change in clinical attachment level (CAL) · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment · 3 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD 0.36 [0.24, 0.48] | 34 studies · 875 participants | Ungraded |
Occlusal splint vs Another occlusal splint with a different mechanism of action Recurrence rate · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 2 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Package of oral health education/promotion including oral hygiene advice for pregnant women, mothers, infants and young children, plus dietary and feeding practice advice for infants and young children vs Standard care Child oral health behaviours · For interventions, pregnant women, mothers or other caregivers of infants in the first year of life; for outcomes,… Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | Three trials (Muhoozi 2017; Pereira 2021; Yu 2021) reported changes in child oral health behaviours (other data): some benefit in favour of the intervention. | 3 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC) prevalence (%, dmft>0) · Children younger than 71 months (under 6 years) · Region: Europe A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 36 [25, 47] | 13 studies | Ungraded |
Fluoride varnish applied before 4 years of age (biannual) vs Placebo varnish Fluorosis (percentage prevalence in permanent teeth) · Children exposed to topical fluoride when under 6 years old; fluorosis assessed in permanent teeth at 6 to 18 years · Fluorosis assessed when most permanent teeth of interest had erupted (6 to 18 years) Topical fluoride as a cause of dental fluorosis in children (2024) · Cochrane | RR 0.77 [0.45, 1.31] | 1 study · 123 participants | Low |
TT+TC genotypes vs CC genotype Dental caries · Children (<18 years) with vs without dental caries · Dominant model (TT+TC vs CC), Primary dentition Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.25 [0.08, 20.04] | NR | Ungraded |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Self-reported joint pain when chewing · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 3 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Facemask with rapid maxillary expansion (RME) vs Facemask only Wits appraisal · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 0.10 [-1.08, 1.29] | 2 studies · 60 participants | Ungraded |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment Participant-reported resumption of normal eating, chewing and speech · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | SoF: participant-reported resumption of normal eating, chewing and speech - outcome not reported by included studies. | 0 studies | No studies |
Pulpotomy (full or partial) vs None (single-arm success proportion) Overall success (composite of clinical and radiographic success) · Permanent teeth with carious pulp exposure · >=12 months, Hemostasis unknown Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.802 | NR | Ungraded |
Single-strand superelastic NiTi arch wire vs Coaxial superelastic NiTi arch wire Alignment rate · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 4 weeks Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | MD -2.64 [-4.61, -0.67] | 2 studies · 64 participants | Moderate |
Mandibular third molar present vs Mandibular third molar absent Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 2.28 [1.67, 3.09] | 4 studies · 467 participants | Low |
Postoperative systemic antibiotics (phenoxymethylpenicillin/penicillin VK, 7-day course), partial or total chemo-mechanical debridement and analgesics vs Matched placebo, partial or total chemo-mechanical debridement and analgesics Pain at 24 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 24 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | MD -0.03 [-0.53, 0.47] | 2 studies · 61 participants | Very low |
TT genotype vs TG+GG genotypes Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TG+GG) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.93 [0.68, 1.29] | 3 studies · 796 participants | Ungraded |
TT+TC genotypes vs CC genotype Dental caries · Children (<18 years) with vs without dental caries · Dominant model (TT+TC vs CC), PCR-RFLP genotyping Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.70 [0.47, 1.05] | NR | Ungraded |
Extraction of the permanent first molar vs None (single-group prevalence) Spontaneous space closure · Children and adolescents (<18 years) after extraction of a permanent first molar before eruption of the permanent… · Until eruption of the permanent second molar (median follow-up 4.0 years), Maxilla Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | Prevalence 85.3 [73.7, 92.3] | 9 studies · 665 participants | Ungraded |
Silver diamine fluoride (SDF) vs Restoration (restorative treatment) Adverse effects · Children and adults (with or without carious lesions) · 12 months, Children Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | Cleary 2022 reported that there were no unanticipated adverse events; adverse events were not defined. | 1 study | Very low |
Milk-based probiotic vs No treatment or placebo (control) Bacterial plaque index · Children and/or adolescents (<18 years) without background systemic disease · Probiotic presentation: milk (vs other presentations; p-interaction=0.01) Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024) | MD -0.10 [-0.20, 0] | NR | Ungraded |
Silver diamine fluoride (SDF) vs Sealants or resin infiltration Adverse effects · Children and adults (with or without carious lesions) · 24 months, Children Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | In 1 study, people complained about a transient bitter taste associated with SDF (with no associated data), with no other adverse effects. In another study, there were no adverse effects. No studies reported this… | 2 studies · 336 participants | Very low |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment Adverse effects · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | Adverse effects (any): 0 in placebo vs 2 minor (flatulence and bloating); 90 (1); no GRADE rating given. | 1 study · 90 participants | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Dental caries, prevalence · Primary school children in Ethiopia · Sampling technique: multi-stage random sampling Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | Prevalence 21 [19, 23] | 1 study · 1736 participants | Ungraded |
Facemask with rapid maxillary expansion (RME) vs Reverse chin cup ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 0.20 [-0.71, 1.11] | 1 study · 42 participants | Ungraded |
G allele vs A allele Dental caries · Children (<18 years) with vs without dental caries · Allelic model (G vs A) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.56 [0.76, 3.24] | 4 studies · 1741 participants | Ungraded |
Vasodilators (isoxsuprine, xanthinol nicotinate) vs Placebo or no active treatment Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD 4.04 [-1.93, 10.02] | 2 studies · 85 participants | Very low |
Occlusal splint vs Acupuncture Recurrence rate · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 5 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Intervention NR Serum vitamin D (25(OH)D): ECC vs caries-free · Region: Asia (Fig 4) The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | Mean difference -14.14 [-15.37, -12.90] | 5 studies | Ungraded |
Oral health education/promotion (oral hygiene advice plus diet and feeding practice advice) combined with clinical treatment for mother's dentition (basic restorative and preventive; 1 trial included CHX varnish application) vs Standard care dmfs index score · For interventions, pregnant women and mothers of infants in the first year of life; for outcomes, children up to 6… Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | dmfs was listed in the SoF table but not assessed (not reported for this comparison). | 0 studies | No studies |
Silver diamine fluoride (SDF) vs Atraumatic restorative treatment (ART) with glass ionomer cement (GIC) or glass ionomer material Dental pain or sensitivity · Children and adults (with or without carious lesions) · 3 months, Children Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | OR 0.16 [0.02, 1.32] | 1 study · 234 participants | Very low |
SDF (given at a particular frequency, concentration, or duration) vs SDF (given at a different frequency, concentration, or duration) Caries arrest · Children and adults (with or without carious lesions) · 12 to 30 months, Primary dentition Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | In 1 study (45 children), 4 applications of 38% SDF at 1-monthly intervals resulted in fewer surfaces with active caries compared with 2 applications at 6-monthly intervals (MD 1.04 surfaces, 95% CI 0.23 to 1.85), and… | 4 studies · 1360 participants | Very low |
Postoperative systemic antibiotics (phenoxymethylpenicillin/penicillin VK, 7-day course), partial or total chemo-mechanical debridement and analgesics vs Matched placebo, partial or total chemo-mechanical debridement and analgesics Swelling at 48 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 48 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | SMD 0.04 [-0.47, 0.55] | 2 studies · 61 participants | Ungraded |
Amorphous calcium phosphate (ACP)-containing light-cure adhesive vs Conventional adhesive (Transbond XT) Enamel demineralization (DIAGNOdent) · Patients undergoing fixed orthodontic (fixed appliance) treatment (adolescents and adults, ages 12 to 35) · 1 and 6 months Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Alshammari 2019 (1 triple-blinded RCT, 26 patients / 255 teeth): DIAGNOdent demineralization scores were lower with ACP than control at 1 month (2.58 +/-1.11 vs 3.39 +/-1.29) and 6 months (3.41 +/-1.11 vs 4.32… | 1 study · 26 participants | Ungraded |
Occlusal splint vs Pharmacological therapy Recurrence rate · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 6 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Dental service utilisation within the past year · Adult residents of slums and non-slum urban settings of LMICs · Past 12 months Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Utilisation within the preceding year ranged from 4% to 72% (e.g., Osuh 4%; Hewlett 10%; Rezaei 60% for treatment and 10% for check-ups; Olutola 72%). | NR | Ungraded |
Occlusal splint vs Pharmacological therapy Discomfort · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 6 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight) Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Adjustment for age: yes Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024) | OR 1.04 [0.84, 1.30] | 6 studies | Ungraded |
Tandem traction bow appliance vs Untreated control (no treatment) ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 1.70 [1.09, 2.31] | 1 study · 30 participants | Ungraded |
Silver diamine fluoride (SDF; 38% in most trials, 30% in three) vs Sodium fluoride varnish (5% NaF) Caries arrestment at the surface level · Children and adults with active dental caries (aged 1-50; mostly preschool/school children with primary dentition) · 12 to 18 months, SDF vs NAF The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024) | OR 1.46 [0.71, 2.98] | 2 studies · 3541 participants | Ungraded |
Facemask vs Untreated control (no treatment) Self-esteem (Piers-Harris self-concept scale) · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · 3-year follow-up Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 0.60 [-2.57, 3.77] | 1 study · 63 participants | Ungraded |
Intervention NR Overall success (composite of clinical and radiographic success) · Immature teeth, unspecified/mixed diagnosis Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.888 [0.816, 0.945] | 6 studies | Ungraded |
Buccal fat pad graft vs Extended nasolabial flap Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · More than 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD 6.50 [-10.72, 23.72] | 1 study · 8 participants | Very low |
Facemask with rapid maxillary expansion (RME) vs Facemask with alternating rapid maxillary expansion and constriction (Alt-RAMEC) ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD -0.46 [-1.03, 0.10] | 4 studies · 131 participants | Low |
Antibacterial S. mutans reduction only in Farzanegan (chitosan+TiO2); Mollabashi (TiO2-only) showed no significant antibacterial effect - not attributable to TiO2 alone vs Conventional adhesive/composite (Transbond XT) Antibacterial effect (Streptococcus mutans count, real-time PCR) · Patients undergoing fixed orthodontic (fixed appliance) treatment (adolescents and adults, ages 12 to 35) · 1 day to 6 months, Antibacterial (S. mutans) Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Two RCTs gave conflicting antibacterial results: Farzanegan 2021 reported a significant decrease in S. mutans with the chitosan plus TiO2 adhesive (p=0.01 lateral incisors; p=0.001 second premolars); Mollabashi 2022… | 2 studies · 64 participants | Ungraded |
Occlusal splint vs Pharmacological therapy Severity of joint noise · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 6 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Intervention NR Overall success (composite of clinical and radiographic success) · Partial pulpotomy, normal pulp/reversible pulpitis Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.920 [0.879, 0.954] | 4 studies | Ungraded |