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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
Oral cancer patients (cases) vs Healthy controls
Clinical attachment loss (CAL) in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, CAL (clinical attachment loss)
Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024)
SMD 1.94 [0.22, 3.66]2 studiesUngraded
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
Pain 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
The median pain at 7 days in the control group was 0 (range 0 to 3); the median pain at 7 days in the intervention group was the same (median 0, range 0 to 1). P = 0.673 (Mann-Whitney U).1 study · 72 participantsLow
Clearfil Protect Bond antibacterial fluoride-releasing primer vs Transbond XT conventional primer
Bracket failure · Patients undergoing fixed orthodontic treatment · During orthodontic treatment
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
No statistically significant difference in bond failure rates was observed between quadrants bonded with Clearfil (CF) and those bonded with the conventional primer (p = 0.316).1 study · 35 participantsUngraded
Occlusal splint vs Another occlusal splint with a different mechanism of action
Discomfort · People with temporomandibular disorders (TMD)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
Listed in Summary of findings 2 as 'Not reported'; this outcome was not reported by any included study for this comparison.0 studiesNo studies
Intervention NR
Dental caries (early childhood caries) · Narrative single study (Ganesh 2022): BF at beginning of sleep
Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024)
AOR 6.71 studyUngraded
High-frequency sugar consumption (three or more times daily) vs Low sugar intake (fewer than three times daily)
Dental caries experience (prevalence) · Nigerian individuals, including children and adults, with primary or permanent dentition · Overall (all dentitions pooled)
A systematic review and meta-analysis of the association between sugar intake and dental caries in Nigeria. (2024)
OR 1.18 [0.87, 1.59]7 studiesUngraded
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) · GNI $20000-$39999
A systematic review and meta-analysis on early-childhood-caries global data. (2024)
Prevalence 30 [22, 38]11 studiesUngraded
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, Dental examination: Parent-reported dental caries
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
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, Dental examination: Clinical oral examinations
Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024)
OR 1.82 [1.47, 2.26]2 studiesUngraded
Grape seed extract or grape seed flavonoid fractions vs No extract or vehicle control; other antimicrobial agents
Bacterial adhesion · Streptococcus mutans cultures and biofilms
Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024)
no estimate extracted2 studiesUngraded
Prophylaxis (teeth cleaning) and CHX or iodine-NaF solution application in the dentition of women (mothers) vs Placebo
Mother caries (dmfs 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 -0.21 [-2.22, 1.79]2 studies · 130 participantsUngraded
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
Endodontic flare-up · 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
RR 0.27 [0.01, 4.90]1 study · 19 participantsUngraded
Low-power CO2 laser irradiation (LLLT, 0.5 to 2 W) vs Placebo / no laser (control)
Incidence of new white spot lesions (WSLs) · High caries-risk patients: fixed-orthodontic-appliance patients and children with partially erupted permanent molars · 3 to 18 months follow-up
Clinical and ex-vivo effect of LASERs on prevention of early-enamel caries: systematic review & meta-analyses. (2024)
OR 0.21 [0.15, 0.30]3 studies · 182 participantsUngraded
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) · GNI <$5000
A systematic review and meta-analysis on early-childhood-caries global data. (2024)
Prevalence 57 [47, 67]19 studiesUngraded
Intervention NR
Overall success (composite of clinical and radiographic success) · Mixed root maturation (both mature and immature teeth)
Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024)
Proportion 0.950 [0.859, 0.998]3 studiesUngraded
Multistrand stainless steel wire vs Wires of other materials (conventional stainless steel, superelastic NiTi, thermoelastic NiTi)
Time to alignment · 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
Time to alignment: not reported0 studiesNo studies
Teledentistry diagnosis using DSLR or smartphone extra-oral photographs vs Visual or clinical examination
Specificity for dental caries diagnosis · 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 extracted13 studiesUngraded
TiO2-modified composite (1 wt.%) vs Control composite in contralateral quadrant
Enamel demineralization (DIAGNOdent score) · Patients undergoing fixed orthodontic treatment · 1 to 6 months after bonding
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
Mean readings were significantly greater on the control side than on the experimental side (p < 0.001) at all time points except at baseline.1 study · 40 participantsUngraded
TT genotype vs TC+CC genotypes
Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TC+CC), Primary dentition
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.49 [0.97, 2.27]NRUngraded
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT
Change in bleeding on probing (BOP) · Adults (> 18 years) with peri-implant mucositis, receiving active treatment · 3 months (change from baseline)
Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane
MD 1.60 [0.27, 2.93]1 study · 38 participantsUngraded
CC+TT (homozygous) genotypes vs CT (heterozygous) genotype
Dental caries · Children (<18 years) with vs without dental caries · Over-dominant model (CC+TT vs CT)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 0.83 [0.67, 1.04]3 studies · 1329 participantsUngraded
A allele vs G allele
Dental caries · Children (<18 years) with vs without dental caries · Allelic model (A vs G)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.07 [0.70, 1.64]3 studies · 855 participantsUngraded
SDF (given at a particular frequency, concentration, or duration) vs SDF (given at a different frequency, concentration, or duration)
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 outcome0 studiesNo studies
Oxitard (antioxidant) vs Aloe vera gel
Difficulty in swallowing (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 0.17 [0.07, 0.44]1 study · 120 participantsUngraded
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) · Life expectancy: >80 years
A systematic review and meta-analysis on early-childhood-caries global data. (2024)
MEAN 1.34NRUngraded
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management)
Participant satisfaction or quality of life · People with temporomandibular disorders (TMD) · Short term (1 month), Mixed TMD
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
MD -1.42 [-15.78, 12.94]2 studies · 73 participantsUngraded
Fluoride varnish applied before 4 years of age vs No fluoride varnish application
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 2.18 [1.46, 3.25]2 studies · 982 participantsLow
Pentoxifylline vs Spirulina
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 -8.00 [-14.47, -1.53]1 study · 40 participantsLow
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), Caucasian ethnicity
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.26 [0.88, 1.80]NRUngraded
Hydrocortisone plus hyaluronidase (intralesional) 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 -4.88 [-12.87, 3.11]1 study · 12 participantsVery low
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Dental caries (prevalence) · Adults · Moderate periodontitis
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 1.38 [1.15, 1.66]7 studiesUngraded
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Dental caries (prevalence) · Adults · Mild periodontitis
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 1.65 [0.45, 6.05]1 studyUngraded
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint)
Muscle pain at rest · People with temporomandibular disorders (TMD) · Short term (mean 2 months), Myofascial pain TMD
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
MD -11.63 [-29.37, 6.11]1 study · 37 participantsVery low
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, Dental examination: Visual examination
Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024)
OR 1.85 [1.59, 2.16]4 studiesUngraded
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy)
Range of mandibular motion · People with temporomandibular disorders (TMD) · Short term (3 months), Disc displacement with reduction (DDwR)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
MD -0.33 [-3.31, 2.65]1 study · 40 participantsUngraded
Multistrand stainless steel wire vs Wires of other materials (conventional stainless steel, superelastic NiTi, thermoelastic NiTi)
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
Occlusal splint vs Another occlusal splint with a different mechanism of action
Muscle pain at rest · People with temporomandibular disorders (TMD)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
Listed in Summary of findings 2 as 'Not reported'; this outcome was not reported by any included study for this comparison.0 studiesNo studies
Nd:YAG laser irradiation vs Untreated control enamel
Enamel acid resistance (cross-sectional microhardness) · Human enamel in pits and fissures (in situ / ex vivo)
Clinical and ex-vivo effect of LASERs on prevention of early-enamel caries: systematic review & meta-analyses. (2024)
Narrative only (not meta-analyzed). Correa-Afonso: Nd:YAG (and CO2) laser increased enamel acid resistance in pits and fissures; microhardness of the Nd:YAG group was higher than the control group.1 studyUngraded
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
dmfs 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
dmfs was listed in the SoF table but not assessed (not reported for this comparison).0 studiesNo studies
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 · Children aged 4 to 6 years whose mothers' prenatal vitamin D status was assessed · Prenatal exposure; dental caries at 4 to 6 years, Children's age subgroup: 4 to 6 years
Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024)
OR 1.44 [1.32, 1.56]8 studiesUngraded
Intralesional triamcinolone vs Intralesional salvianolic acid B
Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · More than 6 months
Interventions for managing oral submucous fibrosis (2024) · Cochrane
MD -0.60 [-3.76, 2.56]1 study · 28 participantsVery low
Cranberry extract or cranberry flavonoid fractions vs No extract or vehicle control; other antimicrobial agents
Antioxidant capacity · Streptococcus mutans cultures and biofilms
Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024)
no estimate extracted1 studyUngraded
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence)
Dental caries, prevalence · Primary school children in Ethiopia · Overall (all included studies)
Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024)
Prevalence 35 [27, 43]7 studies · 3711 participantsUngraded
SDF (given at a particular frequency, concentration, or duration) vs SDF (given at a different frequency, concentration, or duration)
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 reported data for this outcome0 studiesNo studies
Silver diamine fluoride (SDF; 38% in most trials, 30% in three) vs Atraumatic restorative treatment / glass ionomer cement (ART/GIC)
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, SDF vs ART(GIC)
The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024)
OR 1.22 [0.09, 16.34]2 studies · 273 participantsUngraded
Levamisole vs Antioxidant (Antoxid)
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 -9.10 [-16.23, -1.97]1 study · 30 participantsVery low
Levamisole vs Antioxidant (Antoxid)
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 -1.00 [-7.18, 5.18]1 study · 30 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
Swelling 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 0.02 [-0.28, 0.32]1 study · 41 participantsVery low
Silver diamine fluoride (SDF) vs Atraumatic restorative treatment (ART) with glass ionomer cement (GIC) or glass ionomer material
Aesthetics · Children and adults (with or without carious lesions) · 24 months, Children
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
1 study reported that 45% of parents were satisfied with appearance of their child's teeth; data not reported by study group. 1 study reported that 1 of 34 caregivers in SDF group were "annoyed with teeth appearance",…2 studies · 248 participantsVery low
SDF (given at a particular frequency, concentration, or duration) vs SDF (given at a different frequency, concentration, or duration)
Adverse effects · Children and adults (with or without carious lesions) · 24 to 30 months, Children
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
1 study (203 children) reported that black or brown staining on treated lesions was commonly found in both groups, with little or no difference according to whether SDF treatment was given in 3 applications at…3 studies · 1121 participantsVery low