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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 |
|---|---|---|---|
Silver diamine fluoride (SDF) vs Placebo or no treatment Aesthetics · Children and adults (with or without carious lesions) · 30 months, Adults Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | 1 study reported that "only 19 (7%) [older adult participants] raised a complaint about the interventions at the 30-mo [month] examination, and half of them complained of black stain on the treated root surfaces." No… | 1 study · 43 participants | Very low |
Cranberry extract / juice and proanthocyanidin (flavonoid) fractions vs Untreated or vehicle control (some studies vs positive antimicrobial controls, e.g. chlorhexidine/fluoride) Cell death / cytotoxicity induction · Streptococcus mutans (in vitro cultures and biofilms) Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024) | Cranberry extract produced a time- and concentration-dependent reduction in bacterial count, with a 50% reduction after 10 h (Singhal). | 1 study | Ungraded |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Somatisation · People with temporomandibular disorders (TMD) · Short term, Disc displacement with reduction (DDwR) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -0.18 [-0.45, 0.09] | 1 study · 60 participants | Ungraded |
Children with early childhood caries (ECC) vs Caries-free children Serum 25-hydroxyvitamin D level · Preschool children ≤6 years The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | MD -13.96 [-19.88, -8.03] | 9 studies · 3444 participants | Ungraded |
Gene sequencing (GS) applied to diagnose/manage oral conditions (predominantly 16S rRNA next-generation sequencing of the oral microbiome; also genome-wide/whole-genome sequencing) vs Negligible ('abysmal') effect of gene sequencing; no separate comparator arm (within-sample event contrast in the forest plots) Reduction in occurrence of oral conditions · Human patients (any age) with oral-cavity related disorders (e.g. dental caries, periodontitis, gingivitis,… · Overall Gene sequencing applications to combat oral-cavity related disorders: a systematic review with meta-analysis. (2024) | RD -0.29 [-0.32, -0.26] | 8 studies · 2211 participants | Ungraded |
Pentoxifylline 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) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD 1.80 [1.02, 2.58] | 1 study · 106 participants | Low |
Silver diamine fluoride (SDF) vs Restoration (restorative treatment) Primary caries prevention · Children and adults (with or without carious lesions) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | No studies reported data for this outcome in this comparison | 0 studies | No studies |
Silver diamine fluoride (SDF) vs Placebo or no treatment Adverse effects · Children and adults (with or without carious lesions) · 48 hours to 30 months, Children Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | 1 study reported 3 adverse effects in the first 48 hours. Of these, 1 effect in SDF group was possibly related to treatment (spot on corner of lip that looked like a burn), and 2 effects in placebo group were possibly… | 3 studies · 983 participants | Very low |
Silver diamine fluoride (SDF) vs Placebo or no treatment Dental pain or sensitivity · Children and adults (with or without carious lesions) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | No studies measured this outcome | 0 studies | No studies |
Er:YAG laser irradiation of enamel after demineralisation vs No anticaries intervention (untreated enamel) Enamel surface microhardness · Human tooth enamel specimens with early demineralised lesions (in vitro) · Laser applied after demineralisation (no further acid challenge), demineralised enamel Effect of Er:YAG Laser Irradiation on Preventing Enamel Caries: A Systematic Review and Meta-Analysis. (2024) | SMD 0.66 [-1.12, 2.44] | 2 studies | Ungraded |
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight) Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Sample size: <900 Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024) | OR 1.25 [0.77, 2.02] | 8 studies | Ungraded |
Hybrid Hyrax (RME) with miniscrews and Class III elastics vs Conventional Hyrax (RME) with miniscrews and Class III elastics 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 0.28 [-1.08, 1.64] | 1 study · 35 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 clinical attachment level (CAL) · 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 0.07 [-0.21, 0.36] | 5 studies · 204 participants | Ungraded |
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), Mixed dentition Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.85 [0.50, 1.45] | NR | Ungraded |
Intralesional triamcinolone vs Intralesional triamcinolone plus salvianolic acid B 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 -16.30 [-28.15, -4.45] | 1 study · 28 participants | Very low |
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, Mature teeth Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.838 [0.759, 0.904] | NR | Ungraded |
Prophylaxis (teeth cleaning) and CHX or iodine-NaF solution application in the dentition of women (mothers) vs Placebo Mother caries (DMFT increment) · 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 -0.30 [-1.86, 1.26] | 1 study · 66 participants | Ungraded |
Fluoride toothpaste 550 ppm (lower concentration) vs Fluoride toothpaste 1000 ppm (higher concentration) 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 0.75 [0.57, 0.99] | 1 study · 959 participants | Moderate |
Cranberry extract or cranberry flavonoid fractions vs No extract or vehicle control; other antimicrobial agents Biofilm morphology or biomass · Streptococcus mutans cultures and biofilms Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024) | no estimate extracted | 4 studies | Ungraded |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Dental caries (prevalence) · Adults · Male Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.48 [1.26, 1.74] | 2 studies | Ungraded |
Intervention NR Prenatal vitamin D deficiency prevalence · Meta-regression adjusted estimate Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024) | Proportion 0.38 [0.30, 0.46] | NR | Ungraded |
History of toothache vs No history of toothache Dental caries · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 2.99 [2.679, 3.314] | NR | Ungraded |
Silver diamine fluoride (SDF) vs Placebo or no treatment Primary caries prevention · Children and adults (with or without carious lesions) · 36 months, Permanent dentition (coronal) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | MD -0.69 [-0.97, -0.41] | 1 study · 373 participants | Very low |
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, Immature teeth Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.872 [0.803, 0.929] | NR | Ungraded |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Dental caries (prevalence) · Adults · Severe periodontitis Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 2.14 [1.74, 2.64] | 7 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: Middle East A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 72 [58, 85] | 7 studies | Ungraded |
Thermoelastic copper NiTi (CuNiTi) arch wire vs Conventional NiTi arch wire Root resorption · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Root resorption: not reported | 0 studies | No studies |
TT genotype vs TC+CC genotypes Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TC+CC), Asian ethnicity Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.16 [0.85, 1.60] | NR | Ungraded |
Silver diamine fluoride (SDF) vs Silver nitrate plus fluoride varnish Aesthetics · Children and adults (with or without carious lesions) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | No studies reported data for this outcome in this comparison | 0 studies | No studies |
Silver diamine fluoride (SDF) vs Placebo or no treatment Secondary prevention of caries · Children and adults (with or without carious lesions) · 18 months, Primary dentition Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | OR 1.08 [0.52, 2.23] | 1 study · 128 participants | Very low |
C allele vs A allele Dental caries · Children (<18 years) with vs without dental caries · Allelic model (C vs A) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.89 [0.70, 1.14] | 3 studies · 1327 participants | Ungraded |
Intervention NR Decayed, missing, filled surfaces (DMFS) · Periodontal disease severity (CDC-AAP); single study (Robert 2019); adjusted Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.03 [1.01, 1.05] | 1 study | Ungraded |
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control) Streptococcus viridans count (CFU/mL) · Children and/or adolescents (<18 years) without background systemic disease · 6 months, Single study (Mishra 2014); not pooled Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024) | MD 0.40 [0.33, 0.47] | 1 study · 60 participants | Ungraded |
Hydrocortisone plus hyaluronidase (intralesional) vs Triamcinolone plus hyaluronidase (intralesional) Maximal mouth opening (interincisal distance) · 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 | Singh 2010 (hydrocortisone+hyaluronidase 50 vs triamcinolone+hyaluronidase 50): mouth opening reported categorically (trismus) rather than as continuous data, precluding quantitative analysis; authors found no… | 1 study · 100 participants | Ungraded |
Genome-wide common variants (additive dosage; GWAS meta-analysis) vs Genome-wide significance threshold (P<5E-8) Periodontal disease - novel loci (meta-analysis) · Adults from Japanese and European cohorts (present study + GLIDE + UK Biobank + BioBank Japan); periodontal disease… · Lifelong (germline genotype), Meta-analysis: present study + GLIDE + UKB + BBJ Genome-wide association meta-analysis identifies two novel loci associated with dental caries. (2024) | Meta-analysis of periodontal disease identified only previously known loci; no novel loci. The chromosome-19 SIGLEC5 locus associated with periodontitis in Europeans was not replicated in Japanese populations (present… | 4 studies · 764572 participants | Ungraded |
Cesarean section delivery vs Vaginal delivery Early childhood caries (ECC) · Children aged <6 years · Overall (all 24 studies; random-effects) RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024) | OR 1.05 [0.86, 1.30] | 24 studies · 71732 participants | Ungraded |
Silver diamine fluoride (SDF) vs Fluoride varnish Secondary prevention of caries · Children and adults (with or without carious lesions) · Permanent dentition (coronal) 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 |
Presence of oral Candida albicans vs Absence of oral Candida albicans Early childhood caries (ECC) · Children aged ≤6 years (early childhood) · Exposure and outcome assessed concurrently (observational); children aged ≤6 years, Region: America/Canada/Brazil/Chile RETRACTED: Investigating the association between Candida albicans and early childhood dental caries: A… (2024) | OR 3.98 [1.14, 13.87] | 5 studies · 319 participants | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Use of alternative/indigenous mouth-cleaning implements · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Rural/slum vs urban Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Alternative implements included toothpowder, chewing-stick, neem, charcoal, sand, snuff, salt, miswak, cotton wool and the fingers; native/indigenous tools were used more by rural and slum/disadvantaged residents than… | 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 Adverse effects · 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 | No adverse effects reported in the placebo group; 1 participant reported dizziness in the intervention group. 72 participants (1 study). | 1 study · 72 participants | Low |
Er:YAG laser irradiation of sound enamel before acid challenge vs No anticaries intervention (untreated enamel) Enamel mineral loss · Human tooth enamel specimens, sound/intact (in vitro) · After cariogenic acid challenge / pH cycling Effect of Er:YAG Laser Irradiation on Preventing Enamel Caries: A Systematic Review and Meta-Analysis. (2024) | SMD -2.09 [-3.29, -0.88] | 4 studies | Ungraded |
Cleft lip and palate vs No cleft lip and palate Streptococcus mutans mean levels/counts · Children and adolescents aged 0 to 18 years with nonsyndromic cleft lip and palate Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | SMD 1.78 [1.36, 2.19] | 2 studies · 175 participants | Ungraded |
Intervention NR Overall success (composite of clinical and radiographic success) · Partial pulpotomy, irreversible pulpitis Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.826 [0.754, 0.889] | 6 studies | Ungraded |
Cesarean section delivery vs Vaginal delivery Early childhood caries (ECC) · Children aged <6 years · Confounder adjustment: Yes RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024) | OR 1.11 [0.89, 1.37] | 9 studies | Ungraded |
Silver diamine fluoride (SDF) vs Chlorhexidine varnish Adverse effects · Children and adults (with or without carious lesions) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | No studies reported data for this outcome in this comparison | 0 studies | No studies |
Facemask (with frame internal fixation) vs Frankel III functional appliance 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 -0.11 [-1.29, 1.07] | 1 study · 34 participants | Ungraded |
Facemask (RME) or modified facemask vs Other non-surgical orthodontic treatments (mini maxillary protractor, Pushing Splints, modified tandem, Reverse Forsus, reverse Twin Block, reverse chin cup, tongue appliance, Frankel III) 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 0.96 [-0.12, 2.04] | 4 studies · 136 participants | Very low |
Institutionalization (living in an orphanage/institution) vs Parented children living with their families Primary-teeth caries experience (dmf/dmft, mean score) · Institutionalized orphan children (roughly 3 to 18 years) · Overall (pooled) Caries in orphan children: prevalence and determinants-a systematic review and meta-analysis. (2024) | MD 0.64 [-0.74, 2.01] | 4 studies · 1028 participants | Very low |
Overweight vs Normal weight (eutrophic) Dental caries prevalence (any dmft), dichotomous · Brazilian children in primary dentition (BMI classified by CDC 2000 growth charts) Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024) | OR 1.02 [0.69, 1.53] | 2 studies · 734 participants | Very low |
Extraction of the mandibular permanent first molar vs None (single-group prevalence) Rotation of the mandibular first premolar · 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) | Prevalence 37.8 [0.7, 98.2] | 2 studies · 109 participants | Ungraded |