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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 |
|---|---|---|---|
Overweight/obesity (combined) vs Normal weight (eutrophic) Dental caries prevalence (any DMFT), dichotomous · Brazilian children/adolescents in permanent dentition (BMI classified by WHO 2007 Z-score) Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024) | OR 0.93 [0.78, 1.12] | 2 studies | Low |
Abdominal dermal fat graft vs 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) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -14.87 [-19.93, -9.81] | 1 study · 30 participants | Very low |
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) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD 6.00 [-11.36, 23.36] | 1 study · 8 participants | Very low |
Thermoelastic copper NiTi (CuNiTi) arch wire vs Conventional 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 0.10 [-0.95, 1.15] | 1 study · 66 participants | Very low |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Root caries · Adults · Root caries Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 2.10 [1.03, 4.29] | 4 studies | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Use of toothbrush and toothpaste for mouth cleaning · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Slum/disadvantaged/rural vs non-slum/urban Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Eleven studies addressed practices; toothbrush and toothpaste were the commonest cleaning method but their use was lower among slum/disadvantaged/rural groups than non-slum/urban groups (e.g., Osuh 78% slum vs 94%… | 11 studies | Ungraded |
Intervention NR Dental caries (early childhood caries) · Narrative single study (Ganesh 2022): BF during sleep Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | AOR 6.5 | 1 study | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Outcome NR · Adults (> 18 years) with peri-implant mucositis, receiving supportive treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Planned comparison; no studies met the inclusion criteria. The review found only one study of peri-implant disease (peri-implant mucositis, active treatment) and no studies including people with peri-implantitis… | NR | No studies |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · Region: Asia-Oceania A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 3.87 [2.84, 4.91] | 30 studies | Ungraded |
TT genotype vs TC+CC genotypes Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TC+CC), Permanent dentition Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.36 [0.89, 2.08] | NR | Ungraded |
Single preoperative dose of systemic antibiotics (clindamycin 600 mg), total chemo-mechanical debridement and root filling vs Matched placebo, total chemo-mechanical debridement and root filling Swelling at 7 days · Adults with symptomatic apical periodontitis (no signs of spreading infection or systemic involvement) · 7 days Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | RR 0.50 [0.10, 2.56] | 1 study · 72 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 Mother microbiological presence (mutans streptococci colonisation level, CFU/mL) · 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 | MD 0.50 [0.15, 0.85] | 1 study · 126 participants | Ungraded |
Prenatal vitamin D deficiency measured at 6 to 38 gestational weeks vs Normal or sufficient prenatal vitamin D level Dental caries · Children aged 2 to 8 years · Maternal gestational weeks 6 to 38, Vitamin D measurement at 6 to 38 gestational weeks Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024) | OR 1.32 | NR | Ungraded |
Facemask vs Untreated control (no treatment) ANB · 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 1.40 [0.43, 2.37] | 1 study · 63 participants | Moderate |
Vasodilators (isoxsuprine, xanthinol nicotinate) vs Placebo or no active treatment Burning sensation (VAS 0-100) · 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 -51.02 [-72.85, -29.20] | 2 studies · 85 participants | Very low |
Facemask with rapid maxillary expansion (RME) vs Pushing Splints Adverse effects · 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 | Galeotti 2021: occasional skin irritation on the chin and three appliance breakages (one facemask, two Pushing Splints). | 1 study · 42 participants | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Dental caries, prevalence · Primary school children in Ethiopia · Sampling technique: simple random sampling Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | Prevalence 42 [35, 49] | 4 studies · 1421 participants | Ungraded |
Full pulpotomy vs Partial pulpotomy Overall success (composite of clinical and radiographic success) · Mature permanent teeth with symptomatic irreversible pulpitis and carious pulp exposure · >=12 months Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | OR 2.16 [0.92, 5.07] | 3 studies | Ungraded |
Silver diamine fluoride (SDF) vs Sealants or resin infiltration Primary caries prevention · Children and adults (with or without carious lesions) · Primary dentition Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | No studies reported data in this dentition type | 0 studies | No studies |
Unilateral extraction of the mandibular first permanent molar vs Bilateral extraction of the mandibular first permanent molars Midline deviation of the mandibular arch · 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 11.6 [1.9, 70.3] | 1 study | Ungraded |
Topical curcumin gel vs Topical aloe vera gel Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD 16.00 [7.21, 24.79] | 1 study · 60 participants | Very 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 defs index score (categories) · 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 | Thorild 2003 defs score categories (very low-certainty): 1-3 defs RR 0.48 (95% CI 0.15 to 1.54); 3-4 defs RR 0.85 (95% CI 0.18 to 3.98); >=5 defs RR 0.28 (95% CI 0.01 to 6.78); 96 participants. | 1 study · 96 participants | Very low |
Facemask (RME) or modified facemask vs Surgically-anchored appliance (miniscrews or miniplates) 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 0.50 [-1.27, 2.27] | 1 study · 43 participants | Ungraded |
Facemask with rapid maxillary expansion (RME) vs Pushing Splints 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 0.80 [-0.37, 1.97] | 1 study · 42 participants | 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) · Life expectancy: 71-75 years A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 62 | NR | Ungraded |
Vasodilators (isoxsuprine, xanthinol nicotinate) 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 placebo vs 14 minor (transient flushing and upper trunk warmness); 85 (2); no GRADE rating. | 2 studies · 85 participants | Ungraded |
Mineral trioxide aggregate (MTA) vs Calcium hydroxide (CH) Overall success (composite of clinical and radiographic success) · Permanent teeth with carious pulp exposure · >=12 months, Partial pulpotomy Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | OR 2.81 [1.38, 5.74] | NR | Ungraded |
Maternal smoking during pregnancy vs No maternal smoking during pregnancy Dental caries in children · Children of mothers assessed for smoking status during pregnancy (early childhood dental caries) · Exposure during pregnancy; caries assessed in early childhood, Overall (all 12 studies pooled) Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.774 [1.554, 2.026] | 12 studies · 90405 participants | 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 bleeding on probing (BOP) · Adults (> 18 years) with recurrent periodontitis, receiving supportive (maintenance) periodontal care · 3 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD 2.38 [-1.34, 6.10] | 5 studies · 231 participants | Ungraded |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment Intolerance to spicy food (participant-reported proxy) · 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 | OR 0.02 [0.00, 0.43] | 1 study · 100 participants | Ungraded |
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control) Gingival index · Children and/or adolescents (<18 years) without background systemic disease · follow-up: mean 3.07 months, Overall (all presentations pooled) Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024) | MD 0.04 [-0.18, 0.27] | 3 studies · 144 participants | Low |
Grape seed extract or grape seed flavonoid fractions vs No extract or vehicle control; other antimicrobial agents Bacterial growth inhibition · Streptococcus mutans cultures and biofilms Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024) | no estimate extracted | 5 studies | Ungraded |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Muscle pain when chewing · People with temporomandibular disorders (TMD) · Short term (3 months), Disc displacement without reduction (DDwoR) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -1.97 [-2.37, -1.57] | 1 study · 84 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 Pain at 72 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 72 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | MD 0.08 [-0.38, 0.54] | 2 studies · 61 participants | Very low |
Facemask vs Untreated control (no treatment) Self-esteem (Oral Aesthetic Subjective Impact Score, OASIS) · 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 -4.00 [-7.40, -0.60] | 1 study · 69 participants | Ungraded |
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate) Association between patient age and number of ICLs · Patients (permanent dentition) during or after fixed orthodontic treatment with fixed (multibracket) appliances · During or after fixed orthodontic treatment, By patient age (subgroup meta-analysis; no significant association) Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024) | No significant association found between patient age and the number of ICLs (meta-regression / subgroup analysis) | NR | Ungraded |
Absence of toothpaste use vs Toothpaste use Dental caries · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 1.42 [-1.278, 4.109] | NR | 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 bleeding on probing (BOP) · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment · 6 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD 5.72 [1.62, 9.81] | 5 studies · 171 participants | Very low |
Reduction in previous year's academic score vs No reduction in academic score Reduction in previous year's academic score · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 5.51 [1.952, 9.066] | NR | Ungraded |
Facemask vs Untreated control (no treatment) ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · 6-year follow-up Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 0.70 [-0.74, 2.14] | 1 study · 65 participants | Low |
Occlusal splint vs Acupuncture Discomfort · 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 |
Second molar at Demirjian stage F-G at extraction vs Second molar at Demirjian stage D-E at extraction 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 0.68 [0.28, 1.66] | 4 studies | Ungraded |
Superelastic NiTi arch wire vs Conventional (stabilised) NiTi arch wire Pain day 1 · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 3 to 7 days Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | MD 0.29 [-0.52, 1.10] | 2 studies · 142 participants | Low |
Occlusal splint vs Pharmacological therapy Muscle pain at mastication · 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 |
Occlusal splint vs Another occlusal splint with a different mechanism of action Joint pain at rest · People with temporomandibular disorders (TMD) · Long term (12 months), Disc displacement with reduction (DDwR) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 7.00 [0.41, 120.16] | 1 study · 20 participants | Very low |
Intervention NR Overall success (composite of clinical and radiographic success) · Partial pulpotomy, mature teeth Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.842 [0.745, 0.921] | 6 studies | Ungraded |
Superelastic NiTi arch wire vs Thermoelastic NiTi arch wire Time to alignment · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 16 weeks Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | MD 0.5 [0.21, 0.79] | 1 study · 32 participants | Low |
TT+CC (homozygous) genotypes vs TC (heterozygous) genotype Dental caries · Children (<18 years) with vs without dental caries · Over-dominant model (TT+CC vs TC), Real-time quantitative PCR genotyping Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.52 [1.10, 2.10] | NR | Ungraded |
Chin cup 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 1.96 [1.58, 2.34] | 1 study · 50 participants | Ungraded |
Bone-anchored intermaxillary traction (BAIMT) vs Removable mandibular retractor (RMR) Adverse effects / patient-reported (pain, self-confidence) · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · During treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | Majanni 2016: BAIMT associated with higher pain early in treatment than RMR (P<0.001); RMR negatively impacted self-confidence more than BAIMT at all time points (P<0.001). | 1 study · 38 participants | Ungraded |