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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.

Limit to evidence status or GRADE (optional)

10,375 questions in 429 reviews · Oral Health

current versions
No 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.

QuestionEffectEvidenceStatus / GRADE
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Mean DFR (decayed, filled root teeth) · Adults · Overall
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
WMD 1.13 [0.48, 1.78]4 studiesUngraded
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
Number of paracetamol (acetaminophen) with codeine tablets required · 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 -0.31 [-3.94, 3.32]1 study · 41 participantsUngraded
M2 Demirjian stages A-D vs M2 Demirjian stages F-H
Spontaneous space closure · Children and adolescents with maxillary permanent first molar extraction · Follow-up to complete eruption of the permanent second molar, Maxilla
Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024)
OR >100.00 [0.02, >100.00]3 studiesUngraded
Indirect bonding using flowable composite adhesive (Opal Bond MV) vs Direct bonding (conventional, Transbond XT)
White spot lesion formation (QLF: fluorescence loss, lesion area) · Patients undergoing fixed orthodontic (fixed appliance) treatment (adolescents and adults, ages 12 to 35) · Before and after treatment (T0 to T1)
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
Atilla 2020 (1 single-blind parallel RCT, 51 patients): the direct-bonding group had significantly greater loss of fluorescence and demineralization and larger lesion areas than the indirect-bonding (flowable…1 study · 51 participantsUngraded
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)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 0.60 [0.28, 1.25]4 studies · 1741 participantsUngraded
Bone-anchored intermaxillary traction (BAIMT) vs Removable mandibular retractor (RMR)
ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · 1-year follow-up
Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane
MD 1.77 [1.58, 1.96]1 study · 38 participantsUngraded
Antioxidant capsules vs Topical aloe vera gel
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
Sudarshan 2012 (topical aloe vera 10 vs antioxidant capsules 10): reported improvement in interincisal distance but no baseline data, so change could not be determined; excluded from meta-analysis.1 study · 20 participantsUngraded
Pentoxifylline vs Multivitamin
Severity of oral/mucosal burning pain/sensation · 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
Rajendran 2006 concluded the intervention reduced pain, but pain intensity evaluations were inadequately defined and from interview data, making mean scores difficult to interpret.1 study · 29 participantsUngraded
Hybrid Hyrax (RME) with miniscrews and Class III elastics vs Conventional Hyrax (RME) with miniscrews and Class III elastics
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 0.55 [-0.40, 1.50]1 study · 35 participantsUngraded
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT
Change in clinical attachment level (CAL) · 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…NRNo studies
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: North America
A systematic review and meta-analysis on early-childhood-caries global data. (2024)
Prevalence 57 [36, 77]5 studiesUngraded
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate)
Incidence of new ICLs (proportion of subjects developing new lesions) · Patients undergoing fixed orthodontic treatment with fixed (multibracket) appliances, followed for development of new… · During fixed orthodontic treatment (development of new lesions), Overall (random-effects model)
Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024)
Proportion 0.48 [0.33, 0.63]7 studies · 533 participantsVery 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
Caries presence in primary teeth · For interventions, pregnant women, mothers or other caregivers of infants in the first year of life; for outcomes,… · Children assessed at 3 yrs
Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane
RR 1.08 [0.34, 3.37]1 study · 148 participantsVery low
High-dose vitamin D3 supplementation during pregnancy (2400 IU/day from pregnancy week 24 to 1 week postpartum, in addition to the recommended 400 IU/day) vs Low-dose (standard) vitamin D supplementation as recommended in national pregnancy guidelines
dmft index score · 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
dmft was listed in the SoF table but not assessed (not reported for this comparison).0 studiesNo studies
Used less than half of the brush of fluoride toothpaste vs Used half or more of the brush
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
OR 0.77 [0.41, 1.46]2 studies · 258 participantsVery low
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
Pocket closure · Adults (> 18 years) with recurrent periodontitis, receiving supportive (maintenance) periodontal care · 6 months (change from baseline)
Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane
No studies measured this outcome at 6 months (SoF row labeled 'Change in pocket depth from baseline to 6 months after treatment'); no studies reported these data at six months after treatment.NRNo 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 microbiological presence (mutans streptococci colonisation) · 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
Yu 2021: MS colonisation level (CFU x10^4) lower with intervention at 2 yrs (MD -2.80) and 3 yrs (MD -15, 95% CI -27.75 to -2.25) but not 1 yr (MD -0.20, 95% CI -0.50 to 0.10); MS-to-total-bacteria ratio lower at 1 yr…1 studyUngraded
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, Study region: Australia
Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024)
OR 1.68 [1.35, 2.10]1 studyUngraded
Intervention NR
Comparable diagnostic accuracy (photographic vs visual examination) · Overall narrative conclusion across included studies
Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024)
Study conclusion (narrative) 17 of 19 studies concluded photographic diagnostic accuracy comparable to visual caries assessment19 studiesUngraded
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Dental caries (prevalence) · Adults · Age 65 to over 75 years
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 1.69 [1.44, 1.98]2 studiesUngraded
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate)
Prevalence of ICLs (proportion of tooth surfaces affected) · Patients (permanent dentition) during or after fixed orthodontic treatment with fixed (multibracket) appliances · During or after fixed orthodontic treatment (cross-sectional/at debonding), Overall (random-effects model)
Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024)
Proportion 0.22 [0.14, 0.33]6 studies · 11583 participantsVery low
Reverse Forsus 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 5.54 [4.40, 6.68]1 study · 22 participantsUngraded
Chin cup (600 g force) vs Chin cup (300 g force)
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 0.10 [-0.31, 0.51]1 study · 40 participantsUngraded
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, Study quality (NOS): low
RETRACTED: Investigating the association between Candida albicans and early childhood dental caries: A… (2024)
OR 5.14 [2.12, 12.48]4 studiesUngraded
Pentoxifylline 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 -7.00 [-28.8, 42.8]1 study · 30 participantsVery low
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate)
Prevalence of ICLs (proportion of subjects affected) · Patients (permanent dentition) during or after fixed orthodontic treatment with fixed (multibracket) appliances · During or after fixed orthodontic treatment (cross-sectional/at debonding), Overall (random-effects model)
Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024)
Proportion 0.57 [0.48, 0.65]13 studies · 1448 participantsVery low
Silver diamine fluoride (SDF) vs Fluoride varnish
Caries arrest · Children and adults (with or without carious lesions) · 30 months, Primary dentition
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
MD -0.13 [-0.87, 0.61]1 study · 309 participantsVery low
TT+TC genotypes vs CC genotype
Dental caries · Children (<18 years) with vs without dental caries · Dominant model (TT+TC vs CC), Mixed dentition
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 0.81 [0.44, 1.51]NRUngraded
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
Any adverse effect related to aPDT · Adults (> 18 years) with recurrent periodontitis, receiving supportive (maintenance) periodontal care
Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane
Risk with control: In 1 study, 1 participant had an abscess (not specified if this was related to aPDT). In 2 other studies, no adverse effects of aPDT were observed. Number of participants (studies): 134 (3 RCTs).…3 studies · 134 participantsModerate
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
SiC30 index score · For interventions, pregnant women, mothers or other caregivers of infants in the first year of life; for outcomes,… · Children assessed at 6 yrs
Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane
MD -0.93 [-1.73, -0.13]1 study · 187 participantsUngraded
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) · Less than 3 months
Interventions for managing oral submucous fibrosis (2024) · Cochrane
MD -38.79 [-52.06, -25.53]2 studies · 85 participantsVery low
Silver diamine fluoride (SDF) vs Atraumatic restorative treatment (ART) with glass ionomer cement (GIC) or glass ionomer material
Caries arrest · Children and adults (with or without carious lesions) · 24 months, Primary dentition
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
OR 1.13 [0.52, 2.45]1 study · 143 participantsVery 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, Full pulpotomy
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
Proportion 0.859NRUngraded
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight)
Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Age: <7 years
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.59 [1.22, 2.07]9 studiesUngraded
NiTi arch wire of one cross-sectional size vs NiTi arch wire of a different cross-sectional size
Alignment rate · 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
Alignment rate: not reported0 studiesNo studies
Facemask vs Untreated control (no treatment)
Perceived need for surgery in adulthood · 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
OR 3.34 [1.21, 9.24]1 study · 65 participantsLow
TT+TC genotypes vs CC genotype
Dental caries · Children (<18 years) with vs without dental caries · Dominant model (TT+TC vs CC), Permanent dentition
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 0.72 [0.48, 1.07]NRUngraded
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)
Periodontal/gingival clinical status (gingival index, biofilm index, probing depth, bleeding on probing, attachment loss) · 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)
Six studies (Ahluwalia, Rawashdeh, Funahashi, Perdikogianni, Quirynen, Costa) reported that patients with CLP had higher gingival index and biofilm/plaque index, deeper probing depth, more bleeding on probing and…6 studiesUngraded
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Crown caries · Adults · Crown caries
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 1.03 [1.01, 1.05]3 studiesUngraded
Prenatal vitamin D deficiency (low maternal 25(OH)D during pregnancy) vs Adequate prenatal vitamin D (sufficient maternal 25(OH)D)
Dental caries in children · Infants and children (aged about 2 to 8 years) whose mothers' vitamin D status was assessed during pregnancy · Prenatal exposure; dental caries in children aged 2 to 8 years, Publication-bias adjustment: Trim & Fill corrected pooled estimate
Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024)
OR 1.28 [1.14, 1.48]NRUngraded
Brushed less than twice per day vs Brushed twice or more per day
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
OR 1.63 [0.81, 3.28]2 studies · 258 participantsVery low
One-step self-adhesive resin without a separate primer (GC Ortho Connect) vs Conventional multi-step adhesive systems (three-step Transbond XT; self-etch primer Transbond Plus)
White spot lesion development (QLF: mineral loss, lesion area/depth, new lesions) · Patients undergoing fixed orthodontic (fixed appliance) treatment (adolescents and adults, ages 12 to 35) · 2 and 4 months
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
Horan 2023 (1 three-arm RCT, 75 patients): the one-step adhesive without primer (GC Ortho Connect) had a significantly higher WSL incidence and larger, deeper lesions than both the three-step and self-etch systems…1 study · 75 participantsUngraded
rs4801882 effect allele G (intron variant in SIGLEC5, chr19:52,127,053) vs Non-effect allele A
Dental caries (meta of mixed phenotypes: present-study self-report + GLIDE clinical DMFS + UKB self-report/dentures) · Adults from Japanese and European cohorts (present-study Japanese direct-to-consumer cohort + GLIDE consortium and UK… · Lifelong (germline genotype), Meta-analysis: present study + GLIDE + UKB
Genome-wide association meta-analysis identifies two novel loci associated with dental caries. (2024)
Z-score (meta) -5.6393 studies · 533348 participantsUngraded
Cesarean section delivery vs Vaginal delivery
Early childhood caries (ECC) · Children aged <6 years · Study quality (NOS): Good
RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024)
OR 0.97 [0.82, 1.14]6 studiesUngraded
Teledentistry diagnosis using DSLR or smartphone extra-oral photographs vs Visual or clinical examination
d/D dft/DFT or dmft/DMFT score differences · Children and adults with primary or permanent dentition · Overall
Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024)
no estimate extracted8 studiesUngraded
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
Direct costs · 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
The trials did not measure costs.0 studiesNo studies
Single-strand superelastic NiTi arch wire vs Coaxial superelastic 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 reported0 studiesNo studies
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: Central/South America
A systematic review and meta-analysis on early-childhood-caries global data. (2024)
Prevalence 34 [20, 48]6 studiesUngraded
Dental caries (DT not equal to 0) vs No dental caries
Periodontitis (prevalence) · Adults · Overall
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 1.79 [1.36, 2.35]5 studiesUngraded
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management)
Discomfort · People with temporomandibular disorders (TMD)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
Listed in Summary of findings 4 as 'Not reported'; this outcome was not reported by any included study for this comparison.0 studiesNo studies