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Search review questions

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
nCaF2 primer vs Control Transbond primer
Enamel demineralization (DIAGNOdent score) · 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 scores in favor of the nCaF2 primer at T1, T3, and T6 (p-value = 0.000).1 study · 31 participantsUngraded
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence)
Proportion of ancient skulls with at least one non-carious cervical lesion (NCCL) · 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 0.014 [0.001, 0.027]6 studies · 805 participantsUngraded
C allele vs T allele
Dental caries · Children (<18 years) with vs without dental caries · Allelic model (C vs T)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.33 [1.03, 1.71]3 studies · 1329 participantsUngraded
Remineralizing orthodontic adhesives vs Control orthodontic adhesives
Enamel remineralization or anti-demineralization · Human teeth with early enamel lesions surrounding orthodontic brackets · 5 days to 6 months
Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024)
no estimate extracted24 studiesUngraded
Extraction of the permanent first molar vs None (single-group prevalence)
Spontaneous space closure · Children and adolescents (<18 years) after extraction of a permanent first molar before eruption of the permanent… · 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 48.1 [34.5, 62.0]11 studies · 1095 participantsUngraded
Periodontitis vs No periodontitis (periodontal health or gingivitis)
Dental caries (prevalence) · Adults · Age 30-64 years
Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024)
OR 1.67 [1.37, 2.03]3 studiesUngraded
Surgically-anchored orthodontic treatment (miniplates) 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)
Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane
SoF2: Perceived need for surgery in adulthood - Not measured.0 studiesNo studies
Cesarean section delivery vs Vaginal delivery
Early childhood caries (ECC) · Children aged <6 years · Study quality (NOS): Low
RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024)
OR 0.95 [0.39, 2.33]6 studiesUngraded
Cesarean section delivery vs Vaginal delivery
Early childhood caries (ECC) · Children aged <6 years · Confounder adjustment: No
RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024)
OR 0.98 [0.66, 1.47]15 studiesUngraded
Higher mean patient age (per 1 year) vs Lower mean patient age (per 1-year decrement)
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 0.59 [0.20, >100.00]3 studiesUngraded
Occlusal splint vs Pharmacological therapy
Frequency of joint noise · People with temporomandibular disorders (TMD)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
Listed in Summary of findings 6 as 'Not reported'; this outcome was not reported by any included study for this comparison.0 studiesNo studies
Spirulina vs Oxitard (antioxidant)
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 -2.60 [-3.82, -1.38]1 study · 50 participantsLow
Silver diamine fluoride (SDF) vs Sealants or resin infiltration
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 outcome0 studiesNo studies
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy)
Depression · People with temporomandibular disorders (TMD) · Short term, Disc displacement with reduction (DDwR)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
MD -0.25 [-0.52, 0.02]1 study · 60 participantsUngraded
CC+CT genotypes vs TT genotype
Dental caries · Children (<18 years) with vs without dental caries · Dominant model (CC+CT vs TT)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.87 [1.15, 3.04]3 studies · 1329 participantsUngraded
Orthodontic removable traction appliance (ORTA) 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 6.20 [5.52, 6.88]1 study · 40 participantsUngraded
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 1.24 [0.89, 1.71]14 studiesUngraded
Superelastic NiTi arch wire vs Thermoelastic 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 [-0.11, 0.91]1 study · 86 participantsUngraded
Used a pea-sized amount of fluoride toothpaste or less vs Used more than a pea-sized amount
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 0.92 [0.66, 1.28]3 studies · 2037 participantsVery low
Intervention NR
Veillonella spp. association with caries (qualitative)
A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2024)
Veillonella spp. associated with caries; no quantitative estimate reported1 studyUngraded
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 24 hours · Adults with symptomatic apical periodontitis (no signs of spreading infection or systemic involvement) · 24 hours
Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane
The median pain at 24 hours in the control group was 3 (range 0 to 10); the median pain at 24 hours in the intervention group was the same (median 3, range 0 to 8). P = 0.219 (Mann-Whitney U).1 study · 72 participantsLow
Occlusal splint vs Acupuncture
Muscle pain when chewing · People with temporomandibular disorders (TMD) · Short term (1 month), Myofascial pain TMD
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
MD 0.10 [-0.80, 1.00]1 study · 40 participantsVery low
Second molar distally 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 1.18 [0.43, 3.21]3 studiesUngraded
Serum 25(OH)D < 50 nmol/l vs Serum 25(OH)D ≥ 75 nmol/l
Early childhood caries (ECC) · Preschool children ≤6 years
The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024)
OR 2.00 [1.76, 2.28]6 studies · 4807 participantsUngraded
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population
Dental caries experience (mean DMFT) · 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)
Mean DMFT (usually reported at population level) ranged from 0.26 to 16.6 across studies; the Missing component was typically highest and the Filled component lowest, reflecting limited access to dental care.12 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, Sample size: <=1000
Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024)
OR 1.63 [1.11, 2.40]3 studiesUngraded
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight)
Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Age: 7-15 years
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.25 [0.87, 1.81]7 studiesUngraded
Lycopene plus intralesional betamethasone vs Placebo
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
Kumar 2007 reported burning sensation using a non-validated scale; not included in quantitative analysis.1 studyUngraded
Buccal fat pad graft vs Extended nasolabial flap
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 -7.25 [-14.19, -0.31]1 study · 8 participantsVery low
Single-strand superelastic NiTi arch wire vs Coaxial superelastic NiTi arch wire
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
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population
Dental trauma prevalence · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Urban vs rural; slum vs non-slum
Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024)
Dental trauma was more prevalent in urban than rural settings and among disadvantaged groups; Osuh 2022 reported 32% (slum) vs 21% (non-slum); Tobin & Ajayi 2017 found 87.5% of trauma cases in urban vs rural areas…NRUngraded
Non-surgical orthodontic treatment (any: facemask, chin cup, tandem traction bow, mandibular headgear, ORTA, reverse Twin Block, Reverse Forsus) vs No treatment
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 4.75 [4.15, 5.35]4 studies · 155 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
Swelling at 24 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 24 hours
Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane
SMD 0.27 [-0.23, 0.78]2 studies · 62 participantsVery low
Intervention NR
Dental caries (early childhood caries) · Narrative single study (Lima 2016): no nocturnal BF vs nocturnal BF at 16 months
Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024)
OR 0.51 [0.39, 0.65]1 studyUngraded
Intralesional steroid injections vs Alternative medicinal treatments
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 -0.57 [-2.34, 1.19]3 studies · 98 participantsLow
Silver diamine fluoride (SDF) vs Sealants or resin infiltration
Primary caries prevention · Children and adults (with or without carious lesions) · Permanent dentition (root)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
No studies reported data in this dentition type0 studiesNo studies
Surgery plus Heister jaw opener vs Surgery plus wooden tongue depressors
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 [0.01, 1.19]1 study · 50 participantsVery low
Occlusal splint vs Another occlusal splint with a different mechanism of action
Frequency of joint noise · People with temporomandibular disorders (TMD) · Short term (3 months), Disc displacement with reduction (DDwR)
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
RR 0.80 [0.07, 9.18]1 study · 9 participantsVery low
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, Sample collection: saliva
RETRACTED: Investigating the association between Candida albicans and early childhood dental caries: A… (2024)
OR 4.70 [2.44, 9.09]7 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
Pain at 48 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 48 hours
Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane
MD 0.32 [-0.22, 0.86]2 studies · 61 participantsUngraded
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 probing pocket depth (PPD) · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment · 6 months (change from baseline)
Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane
MD 0.52 [0.31, 0.74]15 studies · 452 participantsVery low
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy)
Severity of joint noise · People with temporomandibular disorders (TMD) · Long term (4 months), Mixed TMD
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
MD 5.92 [0.18, 11.66]1 study · 20 participantsVery low
Facemask with rapid maxillary expansion (RME) vs Pushing Splints
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 0.70 [-0.60, 2.00]1 study · 42 participantsUngraded
Silver diamine fluoride (SDF) vs Placebo or no treatment
Caries arrest · Children and adults (with or without carious lesions) · 24 months, Permanent dentition (root)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
MD 0.24 [0.12, 0.36]1 study · 158 participantsVery low
AA genotype vs AG+GG genotypes
Dental caries · Children (<18 years) with vs without dental caries · Recessive model (AA vs AG+GG)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.09 [0.70, 1.71]3 studies · 855 participantsUngraded
NiTi arch wire of one cross-sectional size vs NiTi arch wire of a different cross-sectional size
Pain · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 7 days
Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane
Different sizes of NiTi wires (Alhaija 2021; Erdinc 2004); not pooled due to clinical heterogeneity; little or no difference at day 1. Erdinc 0.014 vs 0.016 inch higher pain at day 4 MD 5.00 (0.19 to 9.81) and day 6 MD…2 studies · 149 participantsLow
Teledentistry diagnosis using DSLR or smartphone extra-oral photographs vs Visual or clinical examination
Negative predictive value 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 extracted10 studiesUngraded
Oral cancer patients (cases) vs Healthy controls
Alveolar bone loss (ABL) in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, ABL (alveolar bone loss)
Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024)
SMD 0.18 [-2.34, 2.69]2 studiesUngraded
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management)
Joint pain at rest · People with temporomandibular disorders (TMD) · Short term (1 month), Mixed TMD
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
MD -2.59 [-4.21, -0.97]1 study · 39 participantsVery low
Silver diamine fluoride (SDF) vs Sealants or resin infiltration
Primary caries prevention · Children and adults (with or without carious lesions) · 18 months, Permanent dentition (coronal)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
OR 1.76 [0.74, 4.20]1 study · 242 participantsVery low