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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
Superelastic NiTi arch wire vs Conventional (stabilised) 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
MD 0.40 [-0.10, 0.90]1 study · 88 participantsUngraded
Salivary F. nucleatum level vs Not specified
Salivary S. mutans level · Humans with salivary bacteria measured · Overall
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 6.03 [1.55, 23.45]1 studyUngraded
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population
Dental caries prevalence · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional
Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024)
Prevalence of dental caries varied across age, gender and socioeconomic class, ranging from 13% (Nigeria) to 76% (Central India); prevalence >50% reported in India, Brazil, Malaysia and Rwanda; generally higher in…14 studiesUngraded
Teledentistry (index test): dental caries diagnosis from photographs taken with DSLR or smartphone cameras; store-and-forward vs Visual/clinical dental examination (reference standard)
Positive predictive value · Children and adults with primary or permanent dentition undergoing dental caries assessment · Cross-sectional diagnostic accuracy (index test vs reference standard, in-vivo), Overall (studies reporting PPV; narrative synthesis)
Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024)
PPV 41.8% to 99%10 studiesUngraded
Intervention NR
Oral cancer (OC) · Sensitivity analysis: excluding Moraes et al. [34]
Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024)
OR 2.63 [1.92, 3.62]7 studiesUngraded
Abdominal dermal fat graft vs Nasolabial flap
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
Kania 2022 reported 3/30 serious adverse effects (graft failure) requiring prolonged hospital stay in the abdominal dermal fat graft group; no GRADE rating.1 study · 30 participantsUngraded
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control)
Salivary pH · Children and/or adolescents (<18 years) without background systemic disease · follow-up: mean 1.1 months, Overall (all presentations pooled)
Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024)
MD -0.12 [-0.72, 0.48]3 studies · 137 participantsVery 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
Adverse effects · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 3 days
Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane
1 participant reported diarrhoea (placebo group); 1 participant reported fatigue and reduced energy postoperatively (antibiotic group). 61 participants (2 studies).2 studies · 61 participantsVery 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) · 3-year follow-up
Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane
MD -3.40 [-7.99, 1.19]1 study · 63 participantsUngraded
Intervention NR
Pathogenic bacteria / plaque composition around brackets (fewer pathogenic bacteria with flash-free vs APC; comparable plaque quantity)
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
no estimate extracted1 studyUngraded
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint)
Frequency of joint noise · People with temporomandibular disorders (TMD) · Short term (mean 10 weeks), Myofascial pain TMD
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
RR 1.18 [0.63, 2.20]1 study · 60 participantsVery low
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) · 3 to 6 months
Interventions for managing oral submucous fibrosis (2024) · Cochrane
MD -0.15 [-5.04, 4.74]2 studies · 136 participantsVery low
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 sex: yes
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.30 [0.99, 1.71]10 studiesUngraded
Teledentistry (index test): dental caries diagnosis from photographs taken with DSLR or smartphone cameras; store-and-forward vs Visual/clinical dental examination (reference standard)
Sensitivity · Children and adults with primary or permanent dentition undergoing dental caries assessment · Cross-sectional diagnostic accuracy (index test vs reference standard, in-vivo), Overall (studies reporting sensitivity; narrative synthesis)
Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024)
Sensitivity Overall 48% to 98.3% across 13 studies; sensitivity is lesion-stage dependent: Kohara reported <40% for initial/moderate caries (75-100% for extensive) and early enamel lesions were less sensitive13 studiesUngraded
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate)
Association between orthodontic treatment duration and ICLs incidence · Patients undergoing fixed orthodontic treatment with fixed (multibracket) appliances, followed for development of new… · During or after fixed orthodontic treatment, By orthodontic treatment duration (subgroup meta-analysis; positive association, P<.01)
Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024)
Incidence of new ICLs positively associated with orthodontic treatment duration (meta-regression, P<.01); effect size/slope not available (Fig. 6b image not provided)NRUngraded
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control)
Number of dental caries (carious pieces) · Children and/or adolescents (<18 years) without background systemic disease · follow-up: mean 26 months, Overall (all presentations pooled)
Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024)
MD -0.24 [-0.72, 0.23]6 studies · 1049 participantsLow
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 · 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 -0.28 [-0.83, 0.27]1 study · 96 participantsVery low
Silver diamine fluoride (SDF; 38% in most trials, 30% in three) vs Placebo (inactive control)
Caries arrestment at the individual (patient) level · Children and adults with active dental caries (aged 1-50; mostly preschool/school children with primary dentition) · 3 weeks to 12 months, SDF vs placebo
The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024)
OR 18.10 [3.89, 84.15]2 studies · 102 participantsUngraded
Silver diamine fluoride (SDF) vs Glass ionomer cement (GIC) plus fluoride varnish
Caries arrest · Children and adults (with or without carious lesions) · 6 months, Primary dentition (coronal)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
OR 1.89 [0.61, 5.87]1 study · 69 participantsVery low
Silver diamine fluoride (SDF) vs Fluoride varnish
Secondary prevention of caries · 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 0.04 [-0.30, 0.38]1 study · 309 participantsVery low
Breastfeeding for <6 months vs Breastfeeding for ≥6 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 0.97 [0.88, 1.06]6 studies · 4850 participantsUngraded
Xylitol (low-intensity sweetener/sugar alcohol) in food products (chewing gum, milk, candy, or tablets) vs No treatment (no gum / no intervention)
Change in Mutans streptococci (MS) count in dental plaque · Generally healthy individuals across all age groups (infants to elderly) · Post-consumption endpoint (trial durations 2 wk to 6 mo), Xylitol gum vs no treatment (5 studies, mixed ages)
Clinical Effects of Sugar Substitutes on Cariogenic Bacteria: A Systematic Review and Meta-Analysis. (2024)
SMD -0.73 [-1.09, -0.37]5 studies · 308 participantsUngraded
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence)
Poor (inadequate) oral hygiene (prevalence) · Children (<18 years) with intellectual and developmental disabilities (IDD) in India · Overall
Oral health status of children with intellectual and developmental disabilities in India: a systematic… (2024)
Prevalence 38 [21, 59]5 studies · 1333 participantsUngraded
TT+TC genotypes vs CC genotype
Dental caries · Children (<18 years) with vs without dental caries · Dominant model (TT+TC vs CC)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 0.75 [0.54, 1.05]5 studies · 1606 participantsUngraded
Minimally invasive caries removal (MIT): selective removal to soft dentin, self-limiting chemomechanical removal, or partial/incomplete caries removal vs Conventional caries removal (CT): selective removal to firm dentin, stepwise excavation, or complete caries removal
Restoration/treatment success rate · Patients with deep carious lesions in permanent (mainly posterior) teeth · 1 to 5 years (follow-up varied by study)
Comparative Meta-Analysis of Minimally Invasive and Conventional Approaches for Caries Removal in Permanent… (2024)
Mean success-rate percentage (unweighted study-level mean, 7 studies) MIT 83.6% vs CT 75.4% (Mann-Whitney U = 0.2, p > 0.05; not statistically significant)7 studies · 1305 participantsUngraded
Occlusal splint vs Another occlusal splint with a different mechanism of action
Range of mandibular motion · People with temporomandibular disorders (TMD) · Short term (12 weeks), Mixed TMD
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
MD 0.63 [-3.16, 4.42]1 study · 40 participantsUngraded
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), Primary dentition
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.49 [0.97, 2.28]NRUngraded
TT+TC genotypes vs CC genotype
Dental caries · Children (<18 years) with vs without dental caries · Dominant model (TT+TC vs CC), Asian ethnicity
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 0.69 [0.44, 1.07]NRUngraded
Orthodontic adhesives containing bioactive glass (BAG) particles/nanoparticles (including fluoride- or Ga-doped BAG) vs Conventional/control orthodontic adhesive (e.g., Transbond XT) or negative control
Ion release (fluoride, calcium, phosphate) · Human enamel specimens around orthodontic brackets (in vitro) · 14 days [31] and 20 days [27,28] (per Discussion); ion-release durations for [23,24] not reported, Overall
Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024)
Ion release from BAG-containing adhesives was assessed in 5 studies [23, 24, 27, 28, 31]; a significant increase of phosphate ion release with gallium-doped bioactive glass nanoparticles up to 14 days was reported…5 studiesUngraded
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
Caries presence in primary teeth · For interventions, pregnant women and mothers of infants in the first year of life; for outcomes, children up to 6… · Children assessed at 18-24 months
Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane
RR 0.44 [0.05, 3.95]2 studies · 324 participantsVery low
nCaF2 primer vs Control Transbond primer
Streptococcus mutans count · Patients undergoing fixed orthodontic treatment · 1, 3, and 6 months after bonding
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
Statistically significant difference in bacterial count between the two primers only at T1 (p-value = 0.000).1 study · 31 participantsUngraded
Facemask vs Untreated control (no treatment)
Overjet · 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 2.50 [1.21, 3.79]1 study · 63 participantsModerate
Facemask with rapid maxillary expansion (RME) vs Facemask only
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 1.86 [0.39, 3.33]1 study · 31 participantsLow
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
Participant satisfaction · 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 participant satisfaction.0 studiesNo studies
Grape seed extract (GSE) and its proanthocyanidin fractions vs Untreated or vehicle control (some studies vs positive antimicrobial controls, e.g. chlorhexidine/fluoride)
Biofilm formation (reduction) · Streptococcus mutans (in vitro cultures and biofilms)
Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024)
GSE reduced biofilm formation: 89% (polymeric PAC) vs 79% (dealcoholized wine) (Daglia), inhibition at 4 mg/mL (Zhao), decreased microcolonies with 2000 ug/mL GSE + fluorinol (Furiga), reduction within 30 min…5 studiesUngraded
Superelastic NiTi arch wire vs Thermoelastic NiTi arch wire
Alignment rate · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 4 to 16 weeks
Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane
MD -0.28 [-0.62, 0.06]5 studies · 183 participantsLow
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
dmft index score (decayed, missing, filled primary teeth; range 0-20) · 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
MD -0.90 [-1.85, 0.05]1 study · 340 participantsVery 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), Asian ethnicity
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.38 [1.02, 1.87]NRUngraded
Cranberry extract or cranberry flavonoid fractions vs No extract or vehicle control; other antimicrobial agents
Biofilm formation · Streptococcus mutans cultures and biofilms
Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024)
no estimate extracted10 studiesUngraded
Intralesional betamethasone vs Placebo
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
Goel 2015 (3-arm: intralesional betamethasone vs lycopene vs placebo, 90 per arm): appeared to show increased interincisal distance in both intervention groups vs placebo, but only between-group differences with no…1 study · 180 participantsUngraded
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) · Less than 3 months
Interventions for managing oral submucous fibrosis (2024) · Cochrane
MD -1.00 [-10.37, 8.37]1 study · 28 participantsVery low
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)
Noticeable impact of gene sequencing on diagnosing/managing 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)
OR 0.30 [0.26, 0.33]8 studies · 2211 participantsUngraded
High-frequency sugar consumption (three or more times daily) vs Low sugar intake (fewer than three times daily)
Dental caries experience in permanent dentition · Nigerian individuals with permanent dentition (approximately 12 years and older) · Permanent dentition
A systematic review and meta-analysis of the association between sugar intake and dental caries in Nigeria. (2024)
OR 1.15 [0.88, 1.52]4 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 assessed in children aged 2 to 8 years, Overall (all studies pooled)
Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024)
OR 1.35 [1.22, 1.47]12 studies · 11021 participantsUngraded
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 sex: no
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.74 [1.13, 2.68]6 studiesUngraded
Mineral trioxide aggregate (MTA) vs Calcium hydroxide (CH)
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)
OR 3.17 [1.25, 7.99]NRUngraded
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence)
Proportion of teeth with non-carious cervical lesions (NCCLs) in ancient skulls · Ancient/prehistoric human skulls (excavated/archaeological skeletal remains) · Overall (all included studies)
Investigation of the presence of Non-carious cervical lesions (NCCLs) in ancient adult skulls: analyzing… (2024)
Proportion 0.004 [0.001, 0.006]4 studies · 11578 participantsUngraded
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Dental caries (prevalence) · Adults · Crude OR
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 1.69 [1.41, 2.01]8 studiesUngraded
Overweight 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 1.01 [0.43, 2.35]2 studies · 706 participantsVery low
Sociodemographic and behavioural factors (older age, lower education, lower income, poor oral hygiene/brushing, smoking, disadvantaged/slum residence, sex) vs Referent groups (younger, higher education/income, better oral hygiene, non-slum residence)
Factors associated with oral diseases · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional
Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024)
Fourteen studies reported determinants: older age, less education, lower income, poor oral hygiene behaviour (brushing frequency, technique), infrequent dental visits and disadvantaged/slum residential setting were…14 studiesUngraded