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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 |
|---|---|---|---|
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Frequency of mouth cleaning · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Slum/disadvantaged vs non-slum/urban Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Mouth cleaning was mostly once daily and in the mornings; only a small proportion cleaned at least twice daily (e.g., Osuh 24% slum vs 27% non-slum; Singh 3%; Habib 3.5%; Hewlett 69%). A similar slum/disadvantaged vs… | NR | Ungraded |
Opal Seal fluoride-releasing adhesive vs Transbond XT conventional adhesive White spot lesion rate and volume · Patients undergoing fixed orthodontic treatment · 8 weeks after bonding Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | The WSL volume was lower in the Opal Seal group than in the Clearfil and Transbond XT groups, but there was no significant difference among the groups (p > 0.05). | 1 study · 15 participants | Ungraded |
Advice about a healthy diet (including breastfeeding promotion and sugar avoidance) and feeding practices (e.g. relating to bottle-feeding and sleep) for infants and young children vs Standard care Caries severity (d1 + mfs >= 5) · For interventions, pregnant women, mothers or other caregivers of infants in the first year of life; for outcomes,… · Children assessed at 4 yrs Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | RR 0.68 [0.50, 0.92] | 1 study · 340 participants | Ungraded |
Moderate-severe active dental caries (exposure) vs Caries-free or mild dental caries (control) Salivary IL-8 level (pg/mL) · Children and young adults (3-25 years) Activity and levels of TNF-α, IL-6 and IL-8 in saliva of children and young adults with dental caries: a… (2024) | SMD 57.20 [-18.60, 133.00] | 7 studies · 522 participants | Ungraded |
Farzanegan 2021 = Transbond XT + 1% chitosan + 1% TiO2 (co-intervention); Mollabashi 2022 = TiO2-only composite (1 wt%) vs Conventional adhesive/composite (Transbond XT) Enamel demineralization / white spot lesion prevention (DIAGNOdent, enamel mineral content) · Patients undergoing fixed orthodontic (fixed appliance) treatment (adolescents and adults, ages 12 to 35) · 1 day to 6 months Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Two RCTs (Farzanegan 2021 n=24; Mollabashi 2022 n=40): Mollabashi reported DIAGNOdent readings significantly lower on the TiO2 side than the control side (p<0.001); Farzanegan reported no significant difference in… | 2 studies · 64 participants | Ungraded |
Started toothbrushing with fluoride toothpaste at or before 12 months (earlier start) vs Started after 12 months (later start) 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 0.98 [0.81, 1.18] | 2 studies · 260 participants | Very low |
More than 15 missing teeth vs 15 or fewer missing teeth Oral cancer risk · People with and without more than 15 missing teeth · Missing teeth >15 Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | OR 1.91 [1.01, 3.62] | 5 studies | Ungraded |
Silver diamine fluoride (SDF) vs Restoration (restorative treatment) Secondary prevention of caries · 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 |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Patient satisfaction · Adults (> 18 years) with peri-implant mucositis, receiving active treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Only one study reported evidence for adjunctive aPDT in people with peri-implant disease (Al Rifaiy 2022). Data were only available for two outcomes (PPD and BOP), both reported only at three months. No studies… | NR | No studies |
Calcium fluoride nanoparticle (nCaF2)-containing orthodontic primer vs Conventional primer (Transbond) Enamel demineralization / white spot lesions (DIAGNOdent, photographic scoring) · Patients undergoing fixed orthodontic (fixed appliance) treatment (adolescents and adults, ages 12 to 35) · 1, 3 and 6 months (during treatment to debonding) Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Al Tuma 2023 (1 split-mouth RCT, 31 patients / 310 teeth): DIAGNOdent scores significantly favored the nCaF2 primer at 1, 3 and 6 months (p=0.000) and S. mutans count differed at 1 month; no significant difference in… | 1 study · 31 participants | Ungraded |
Intervention NR Decayed surfaces (DS) · Percentage of sites with CAL >=3 mm (tertiles); single study (Robert 2019); adjusted Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.12 [1.00, 1.25] | 1 study | Ungraded |
Non-surgical orthodontic treatment (any: facemask, chin cup, tandem traction bow, mandibular headgear, ORTA, reverse Twin Block, Reverse Forsus) vs No treatment ANB · 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 3.05 [2.40, 3.71] | 8 studies · 345 participants | Moderate |
Institutionalization (living in an orphanage/institution) vs Parented children living with their families Permanent-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 0.09 [-0.36, 0.55] | 7 studies · 2676 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 Percussion pain at 7 days · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 7 days Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | MD 0.06 [-0.29, 0.41] | 1 study · 41 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 gingival recession (REC) · 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 -0.01 [-0.27, 0.25] | 2 studies · 37 participants | Ungraded |
Intralesional dexamethasone injections vs Placebo injections 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 -2.10 [-6.77, 2.57] | 1 study · 25 participants | Very low |
Dietary advice on how to achieve a healthy diet for infants (tailored advice focused on a diet low in saturated fat and cholesterol intake) vs Standard care Child oral health behaviour · 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 | Data on oral health behaviours from Lapinleimu 1995 (other data) showed no evidence of a difference between groups. | 1 study | Ungraded |
AA+GG (homozygous) genotypes vs GA (heterozygous) genotype Dental caries · Children (<18 years) with vs without dental caries · Over-dominant model (AA+GG vs GA), Zhang 2006 removed, Sensitivity analysis (Zhang 2006 excluded) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.85 [0.48, 1.49] | 3 studies · 1329 participants | Ungraded |
Obesity vs Normal weight (eutrophic) Dental caries prevalence (any DMFT), dichotomous · Brazilian children/adolescents in permanent dentition (BMI classified by CDC 2000 growth charts) Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024) | OR 2.53 [1.49, 4.29] | 2 studies · 659 participants | Moderate |
Intralesional dexamethasone injections vs Placebo injections 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 [-6.30, 2.70] | 1 study · 25 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, Irreversible pulpitis Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.824 [0.746, 0.890] | 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 Quality of life · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | No studies reported data for this outcome. | 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) · Gini index: no inequalities A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 3.95 | NR | Ungraded |
Breastfeeding <18 months vs Breastfeeding ≥18 months Dental caries (ECC) · Preschool children under 6 years of age · First dental examination before age 6 years, Cohort studies; sensitivity analysis excluding studies 48 and 52 Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | RR 0.26 [0.16, 0.42] | 3 studies | Ungraded |
Missing teeth / tooth loss vs Fewer or no missing teeth Oral cancer (OC) · Adults in case-control studies of oral cancer · Not specified, Overall (all missing-teeth measures pooled) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | OR 1.20 [0.97, 1.48] | 6 studies | 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, Children's age: >3 years Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.83 [1.53, 2.18] | 5 studies | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Oral disease burden, slum vs non-slum urban comparison · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Slum vs non-slum urban / general population Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Five studies compared slum with non-slum urban or national populations: Airen 2014 (caries 76% slum vs 50-60% general), Patel 2017 and Osuh 2022 (higher oral disease prevalence in slum vs non-slum urban sites), Singh… | 5 studies | Ungraded |
Genome-wide common variants (additive dosage; present-study GWAS) vs Genome-wide significance threshold (P<5E-8) Dental caries - genome-wide-significant loci · Japanese adults (present-study cohort: 30,859 dental caries cases / 14,666 controls) · Lifelong (germline genotype), Present-study GWAS (Japanese) Genome-wide association meta-analysis identifies two novel loci associated with dental caries. (2024) | In the present Japanese GWAS, no loci reached genome-wide significance (P<5E-8) for dental caries; several loci reached the suggestive level (P<1E-5). Top-associated variant rs140784657 (intergenic). All 47 lead… | 1 study · 45525 participants | Ungraded |
Second molar mesially inclined at extraction vs Second molar upright 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 [0.27, 1.71] | 3 studies | Ungraded |
Breastfeeding (exclusive or partial, any duration) vs No breastfeeding Dental caries (early childhood caries) · Preschool children (<6 years) · Cohort studies Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | RR 0.98 [0.77, 1.26] | 10 studies · 8506 participants | Ungraded |
Silver diamine fluoride (SDF; 38% in most trials, 30% in three) vs Other methods (pooled: ART/glass ionomer cement, nano-silver fluoride, sodium fluoride varnish) Caries arrestment at the tooth level · Children and adults with active dental caries (aged 1-50; mostly preschool/school children with primary dentition) · 6 to 12 months, Overall (all comparators pooled) The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024) | OR 1.74 [0.88, 3.46] | 5 studies · 743 participants | Moderate |
Breastfeeding for <4 months vs Breastfeeding for ≥4 months Dental caries (early childhood caries) · Preschool children (<6 years) · Cohort studies Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | RR 0.95 [0.80, 1.13] | 2 studies · 1017 participants | Ungraded |
Facemask with rapid maxillary expansion (RME) vs Reverse Forsus 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 0.46 [-0.90, 1.82] | 1 study · 30 participants | Ungraded |
Intervention NR Cariogenic microbiota counts (Streptococcus mutans, Lactobacillus spp.) · Narrative synthesis: significantly higher in CLP vs controls (Ahluwalia, Lucas, Hassani, Cheng, Sundell) Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | no estimate extracted | 5 studies | Ungraded |
Intervention NR Overall success (composite of clinical and radiographic success) · Immature teeth, normal pulp/reversible pulpitis Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.892 [0.834, 0.940] | 2 studies | Ungraded |
Silver diamine fluoride (SDF) vs Restoration (restorative treatment) Dental pain or sensitivity · 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 | OR 9.14 [0.49, 172.21] | 1 study · 69 participants | Very low |
nCaF2 primer vs Control Transbond primer Photographic white spot lesion score · Patients undergoing fixed orthodontic treatment · Before and after treatment Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | No significant differences in the WSLs photographic scores of the control group with the contralateral nCaF2 group before and after bonding. | 1 study · 31 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) · Overall (all regions) A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 49 [44, 55] | 67 studies | Ungraded |
Silver diamine fluoride (SDF) vs Silver nitrate plus fluoride varnish Secondary prevention of caries · 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 |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Any adverse effect related to aPDT · Adults (> 18 years) with peri-implant mucositis, receiving active treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Only one study reported evidence for adjunctive aPDT in people with peri-implant disease (Al Rifaiy 2022). Data were only available for two outcomes (PPD and BOP), both reported only at three months. No studies… | NR | No studies |
Cesarean section delivery vs Vaginal delivery Early childhood caries (ECC) · Children with average age ≤3 years · Average age: ≤3 years RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024) | OR 0.86 [0.67, 1.10] | 10 studies | Ungraded |
Obesity vs Normal weight (eutrophic) Dental caries experience (dmft), continuous · 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) | MD -0.34 [-0.96, 0.27] | 2 studies · 710 participants | Very low |
Surgery plus Heister jaw opener vs Surgery plus wooden tongue depressors Burning sensation (VAS 0-100) · 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 | Vadepally 2019 measured burning sensation on a VAS but did not fully report results, stating there was no significant difference between the 2 groups (p=0.617). | 1 study · 50 participants | Ungraded |
Consumption of xylitol chewing gum by women (mothers) vs Consumption of CHX/xylitol gum by women, or CHX varnish applied to women's dentition 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 |
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, Children's age: <=3 years Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.70 [1.50, 1.91] | 7 studies | 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, Sample size: >1000 and ≤3000 Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.70 [1.48, 1.88] | 7 studies | Ungraded |
Oxitard (antioxidant) vs Aloe vera gel Difficulty in speech (participant-reported proxy) · 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 | OR 0.32 [0.14, 0.76] | 1 study · 120 participants | Ungraded |
Advice about a healthy diet (including breastfeeding promotion and sugar avoidance) and feeding practices (e.g. relating to bottle-feeding and sleep) for infants and young children vs Standard care Mother self-reported oral health behaviours and attitudes · 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 | One trial (Watt 2009) reported mother self-reported oral health behaviours (other data): some benefit in favour of the intervention. | 1 study | Ungraded |
Experimental orthodontic adhesive containing amorphous fluorinated calcium phosphate nanoparticles (n-AFCP) vs Conventional/control orthodontic adhesive (e.g., Transbond XT) or negative control Enamel remineralization extent and color change · Human enamel specimens around orthodontic brackets (in vitro) · pH cycling 21 days, Overall Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024) | A study using an orthodontic primer containing amorphous fluorinated calcium phosphate nanoparticles showed statistically significant remineralization and less enamel color change (delta-E) compared with the control… | 1 study | Ungraded |
Single-strand superelastic NiTi arch wire vs Coaxial superelastic NiTi arch wire Time to next/working arch wire · 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 | No studies reported time to next/working arch wire | 0 studies | No studies |