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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. Every word you type has to appear somewhere in the question, and the closest matches are ranked first.

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
Food and nonalcoholic beverage marketing (exposure) vs No, less, or less powerful food marketing
Purchase requests · Children and adolescents aged 0-19 years · Nonrandomized studies
Association of Food and Nonalcoholic Beverage Marketing With Children and Adolescents' Eating Behaviors and… (2022)
A single observational study contributed to the combination-of-P-values analysis for purchase requests.1 studyVery low
Primary school-based interventions (one or more of: school health policy, oral health education, healthy school environment, access to oral health services, community involvement) vs No intervention or usual practice/activities
Dental caries prevalence measured by dmft or DMFT/S score greater than one · Primary school children (aged 3-16 years) attending primary school in low- and middle-income countries (LMICs) · <2 years, Intervention duration <2 years
Effectiveness of primary school-based interventions in improving oral health of children in low- and… (2022)
RR 0.95 [0.75, 1.21]2 studiesUngraded
Dental caries assessment (WHO/clinical diagnostic criteria; caries = DMFT>0) vs None (descriptive prevalence review; subgroup analyses by urban/rural status, country and year)
Caries prevalence · 12-year-old children (permanent dentition) in Africa · Country: The Gambia
Prevalence of dental caries in the permanent dentition amongst 12-year-olds in Africa: a systematic review… (2022)
Prevalence 0.30 [0.239, 0.375]1 studyUngraded
Prior SDF application without a rinsing step vs No prior SDF application (untreated dentin control)
Immediate bond strength (MPa) · Glass-ionomer cement bonded to sound dentin (in vitro) · Immediate bond strength, Sound dentin (without rinsing step)
Bonding of Glass-Ionomer Cement and Adhesives to Silver Diamine Fluoride-treated Dentin: An Updated… (2022)
MD 0.26 [-0.20, 0.73]5 studies · 218 participantsUngraded
Intervention NR
Difference in summary sensitivity (NMA, Analysis 2) · Fluorescence vs Imaging
Enamel Caries Detection and Diagnosis: An Analysis of Systematic Reviews. (2022)
Sensitivity difference (95% CrI) 0.26 [0.15, 0.37]NRUngraded
Atraumatic restorative treatment with high-viscosity GIC (class I) vs Amalgam restoration
Restoration success/failure · Children (5-7 years) with caries in primary teeth · 24 months
Minimal intervention dentistry for managing carious lesions into dentine in primary teeth: an umbrella review. (2022)
RR 1.07 [0.91, 1.27]3 studiesUngraded
Amalgam vs Compomer
Restoration failure · Children with carious primary teeth · 2 years, Class II
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) amalgam 1.0%; compomer 1.0%1 study · 75 participantsUngraded
Combined antiretroviral therapy (cART) vs Monotherapy or dual antiretroviral therapy
Dental development and maturation · Children and adolescents (<18 years) living with HIV (CLWH)
Impact of Antiretroviral Therapy on Oral Health among Children Living with HIV: A Systematic Review and… (2022)
No eligible studies compared dental development and maturation between CLWH on different ART medications.0 studiesNo studies
Glass ionomer-based sealant vs No sealant
Development of >=1 new carious lesion (caries incidence) · Children with caries-free primary first molars (with or without caries on other teeth), aged 1-5 years (paediatric… · 12-30 months
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
OR 0.97 [0.63, 1.49]1 study · 449 participantsLow
Plasma rich in growth factors (PRGF) vs Alvogyl
Pain (VAS cm) · Adults (>18 years) with established dry socket following permanent tooth extraction · Day 7 (also day 3)
Local interventions for the management of alveolar osteitis (dry socket) (2022) · Cochrane
MD -0.40 [-1.77, 0.97]1 study · 44 participantsUngraded
Recombinant bovine fibroblast growth factor gel vs Control
Presence of dry socket · Adults (>18 years) having permanent tooth extraction (predominantly mandibular third molars) · Follow-up: median 7 days
Local interventions for the management of alveolar osteitis (dry socket) (2022) · Cochrane
RR 0.10 [0.01, 0.76]1 study · 160 participantsUngraded
Dental caries (early childhood caries, ECC) vs Caries-free controls
Relative abundance of Veillonella spp. · Children with early childhood caries (ECC) and caries-free children · Saliva
Meta-Analysis Using NGS Data: The Veillonella Species in Dental Caries. (2022)
MD -1.05 [-7.67, 5.57]2 studies · 161 participantsUngraded
Neocone vs Zinc oxide eugenol
Time to initial pain relief (minutes) · Adults (>18 years) with established dry socket following permanent tooth extraction · Initial pain relief
Local interventions for the management of alveolar osteitis (dry socket) (2022) · Cochrane
MD -7.77 [-8.86, -6.68]1 study · 78 participantsUngraded
Relaxation vs Occlusal (oral) appliance
Adverse events · People aged 12 years and over with painful TMD lasting 3 months or longer · Adolescents (12-19 years)
Psychological therapies for temporomandibular disorders (TMDs) (2022) · Cochrane
Wahlund 2015: reported no adverse treatment effects from treatment with an occlusal appliance or with relaxation therapy.1 studyUngraded
Caries experience measurement (mean D(M)FS, enamel lesions included) vs None (descriptive prevalence review; subgroup analyses only)
Caries experience (mean DMFS) · European adolescents aged 12–19 years · Examination year: ≥ 2010
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
MEAN 5.21 [2.30, 11.81]6 studiesUngraded
Caries assessment at enamel threshold (D(M)FS>0 or D(M)FT>0, enamel lesions included) vs None (descriptive prevalence review; subgroup analyses only)
Caries prevalence · European adolescents aged 12–19 years · Region: Scandinavian
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
Prevalence 0.76 [0.65, 0.87]11 studiesUngraded
Cognitive behavioural therapy (CBT) vs Usual care, waiting list or no treatment (control)
Pain intensity at follow-up (12 months) · People aged 12 years and over with painful TMD lasting 3 months or longer · Follow-up (12 months)
Psychological therapies for temporomandibular disorders (TMDs) (2022) · Cochrane
SMD -0.30 [-0.51, -0.09]6 studies · 639 participantsLow
Machine-learning algorithms for dental caries detection vs Different machine-learning algorithms for caries prediction
Molar and premolar caries detection accuracy · Dental images of human beings · Lee et al., 2018; CNN
Uses of Different Machine Learning Algorithms for Diagnosis of Dental Caries. (2022)
Accuracy 821 study · 3000 participantsUngraded
Compomer vs HVGIC Equia Forte and Chemfil Rock
Restoration failure · Children with carious primary teeth · 1 year, Class II
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) compomer 3.6%; HVGIC 25.6% and 13.4%1 study · 63 participantsUngraded
Professional oral care vs Usual oral care
Mortality (pneumonia-associated) · Residents of nursing homes and other long-term care facilities · 24 months
Oral care measures for preventing nursing home‐acquired pneumonia (2022) · Cochrane
RR 0.43 [0.25, 0.76]2 studies · 454 participantsLow
Caries experience measurement (mean D(M)FS, enamel lesions included) vs None (descriptive prevalence review; subgroup analyses only)
Caries experience (mean DMFS) · European adolescents aged 12–19 years · Examination year: < 2010
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
MEAN 7.54 [5.46, 10.43]7 studiesUngraded
Food and nonalcoholic beverage marketing (exposure) vs No, less, or less powerful food marketing
Food choice · Children and adolescents aged 0-19 years · Randomized trials
Association of Food and Nonalcoholic Beverage Marketing With Children and Adolescents' Eating Behaviors and… (2022)
OR 1.97 [1.46, 2.66]22 studies · 3838 participantsModerate
Platelet rich fibrin vs Control
Presence of dry socket · Adults (>18 years) having permanent tooth extraction (predominantly mandibular third molars) · Follow-up: median 7 days
Local interventions for the management of alveolar osteitis (dry socket) (2022) · Cochrane
RR 0.44 [0.15, 1.35]1 study · 100 participantsUngraded
Electrical conductance or impedance vs Reference standard (histology, operative excavation, or enhanced visual examination)
Sensitivity for detecting enamel caries · Asymptomatic children or adults suspected of enamel caries (clinical studies); extracted teeth (in vitro studies) · Analysis 2: network meta-analysis (all studies evaluating >=2 index tests)
Enamel Caries Detection and Diagnosis: An Analysis of Systematic Reviews. (2022)
Sensitivity 0.83 [0.66, 0.92]64 studies · 24567 participantsLow
Bulk-fill composite resin with 7-second dentine etching vs Bulk-fill composite resin with 15-second dentine etching
Treatment failure (annual failure rate) · Children (aged 5-8 years) with Class-II caries in primary molars, no pulp therapy · 18 months (Cavalheiro 2020), Dentine etching time (7 s vs 15 s)
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) 15 s 16.9%; 7 s 5.8%1 study · 62 participantsUngraded
Parental tertiary education vs Parental high school (secondary) education
Dental caries (early childhood caries) · Healthy children under 6 years in South Africa
Maternal and infant risk factors and risk indicators associated with early childhood caries in South Africa:… (2022)
OR 1.77 [1.22, 2.57]2 studies · 505 participantsUngraded
Bio-active restorative materials vs Other restorative approaches
Clinical effectiveness · Children with carious primary teeth · At least 12 months
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
no estimate extracted0 studiesNo studies
Chlorhexidine rinse (0.12% and 0.2%, pre- and post-extraction) vs Placebo or no treatment
Adverse events · Adults (>18 years) having permanent tooth extraction (predominantly mandibular third molars) · Follow-up: median 7 days
Local interventions for the management of alveolar osteitis (dry socket) (2022) · Cochrane
3 trials reported no adverse events. 1 study reported adverse events (alterations in taste, bad taste, staining) in 24/62 in chlorhexidine group versus 0/40 in placebo group, Peto OR = 8.42 (95% CI 3.31 to 21.39). A…6 studiesUngraded
Intervention NR
Difference in summary sensitivity (NMA, Analysis 2) · Electrical conductance vs Visual
Enamel Caries Detection and Diagnosis: An Analysis of Systematic Reviews. (2022)
Sensitivity difference (95% CrI) 0.00 [-0.17, 0.11]NRUngraded
Iodine tampon vs Saline irrigation (monoject syringe)
Presence of dry socket · Adults (>18 years) having permanent tooth extraction (predominantly mandibular third molars) · Follow-up: median 7 days
Local interventions for the management of alveolar osteitis (dry socket) (2022) · Cochrane
Iodine tampon versus rinsing with saline in a syringe (Tuk 2019): Iodine tampon 0/54 Monoject with saline 0/54; no events (effect not estimable)1 study · 108 participantsUngraded
Antiretroviral therapy (any, including cART) vs No antiretroviral medication (treatment-naive)
Angular cheilitis prevalence · Children and adolescents (<18 years) living with HIV (CLWH)
Impact of Antiretroviral Therapy on Oral Health among Children Living with HIV: A Systematic Review and… (2022)
OR 0.58 [0.17, 1.99]NRVery low
Caries severity measurement (mean number of decayed, missing and filled permanent teeth, DMFT; WHO criteria) vs None (descriptive prevalence review; subgroup analyses by urban/rural status, country and year)
Caries severity (mean DMFT) · 12-year-old children (permanent dentition) in Africa · Setting: Urban/rural (unspecified)
Prevalence of dental caries in the permanent dentition amongst 12-year-olds in Africa: a systematic review… (2022)
MEAN 1.005 [0.797, 1.212]10 studiesUngraded
Fluoride-free nano-/micro-hydroxyapatite (nHA) dentifrice vs Fluoride-containing (fluoridated) dentifrice control
Caries lesion initiation/progression (ICDAS score, laser fluorescence/DIAGNOdent, photographic pixels, enamel acid resistance) · Patients (children and adults, age 3-40 years) with initial enamel caries lesions (non-orthodontic and orthodontic) · Median follow-up 6 months (range 6-12 months)
Efficacy of nano-hydroxyapatite on caries prevention-a systematic review and meta-analysis. (2022)
No meta-analysis was performed for the in vivo studies owing to high heterogeneity (population, control group, outcomes, follow-up periods, risk of bias) and differing statistical designs (e.g., non-inferiority);…5 studies · 420 participantsUngraded
Antiretroviral therapy (any, including cART) vs No antiretroviral medication (treatment-naive)
Ulcerative stomatitis prevalence · Children and adolescents (<18 years) living with HIV (CLWH)
Impact of Antiretroviral Therapy on Oral Health among Children Living with HIV: A Systematic Review and… (2022)
OR 0.03 [0.02, 0.07]NRVery low
Hypnosis vs Relaxation
Pain intensity · People aged 12 years and over with painful TMD lasting 3 months or longer · Treatment completion
Psychological therapies for temporomandibular disorders (TMDs) (2022) · Cochrane
Not pooled (clinical heterogeneity). Abrahamsen 2011: MD -1.00 (95% CI -2.27 to 0.27), n=38 (hypnosis 19, relaxation 19); Stam 1984: MD not reported, n=27 (hypnosis 12, relaxation 15).2 studies · 65 participantsUngraded
Habit reversal treatment vs Waiting-list control
Pain intensity · People aged 12 years and over with painful TMD lasting 3 months or longer · Treatment completion
Psychological therapies for temporomandibular disorders (TMDs) (2022) · Cochrane
MD -1.31 [-1.97, -0.65]1 study · 20 participantsUngraded
Zirconia crown vs Composite strip crown (filled with hybrid composite)
Treatment failure (annual failure rate) · Children (aged 3-5.5 years) with early childhood caries in anterior primary teeth (>=2 carious surfaces), no pulp… · 12 months (Alaki 2020)
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) zirconia crown 3.3%; composite strip crown 15.0%1 study · 32 participantsUngraded
Intervention NR
Caries experience - mean dft (descriptive), primary dentition · CL/P vs no CL/P; Table 4 (1 group/1 study, Howe 2017)
Caries in children with and without orofacial clefting: A systematic review and meta-analysis. (2022)
Mean dft (SD) CL/P 0.59 (SD 1.35) vs no CL/P 0.11 (SD 0.54)1 studyUngraded
Alvogyl vs No treatment
Pain (VAS) · Adults (>18 years) with established dry socket following permanent tooth extraction
Local interventions for the management of alveolar osteitis (dry socket) (2022) · Cochrane
Alvogyl versus No treatment (Kaya 2011): data not usable (medians presented with error bars). Text reports differences in clinical signs and symptoms between control and all 3 treatment groups significant (P<0.05) at…1 studyUngraded
Caries assessment at enamel threshold vs None
Caries prevalence · European adolescents aged 12–19 years · Examination year: ≥ 2010
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
Prevalence 0.74 [0.53, 0.96]11 studiesUngraded
Periodontal treatment: scaling and root planing (SRP) plus advice vs Community care: advice only
All-cause death · People with cardiovascular disease and chronic periodontitis
Periodontal therapy for primary or secondary prevention of cardiovascular disease in people with periodontitis (2022) · Cochrane
SoF row 'All-cause death': Outcome not reported. Results 2.1.1: Not reported.0 studiesNo studies
Povidone iodine vs Ozonated water
Reduction in level of contamination by particles <=5 um (droplet nuclei) at >=2 m from patient's oral cavity · Dental patients undergoing aerosol-generating procedures (AGPs) and the dental healthcare providers treating them · droplet nuclei; aerobic cultures
Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental… (2022) · Cochrane
MD -12.5 [-26.33, 1.33]1 study · 40 participantsVery low
Living with HIV and undergoing antiretroviral therapy (ART/HAART) vs Healthy HIV-negative controls
Acute necrotizing ulcerative gingivitis/periodontitis (WHO clinical stage 3) · Children and adolescents (<18 years) · Cross-sectional (case-control; single time point)
Oral Health Status of Children and Adolescents Living with HIV Undergoing Antiretroviral Therapy: A… (2022)
Planned WHO stage 3 outcome; no eligible studies (Table 2 lists 'None').0 studiesNo studies
Periodontal treatment (subgingival instrumentation, with or without antimicrobials/surgery) vs No active intervention/usual care
Bleeding on probing (BOP) · People with diabetes mellitus (type 1 or type 2, mostly type 2) and periodontitis, at least 16 years of age · 3-4 months
Treatment of periodontitis for glycaemic control in people with diabetes mellitus (2022) · Cochrane
MD -15.56 [-21.77, -9.36]14 studiesUngraded
Caries assessment at enamel threshold (D(M)FS>0 or D(M)FT>0, enamel lesions included) vs None (descriptive prevalence review; subgroup analyses only)
Caries prevalence · European adolescents aged 12–19 years · Publication year: < 2010
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
Prevalence 0.83 [0.75, 0.89]7 studiesUngraded
Caries assessment at enamel threshold (D(M)FS>0 or D(M)FT>0, enamel lesions included) vs None (descriptive prevalence review; subgroup analyses only)
Caries prevalence · European adolescents aged 12–19 years
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
Prevalence 0.77 [0.65, 0.89]22 studies · 84512 participantsUngraded
Primary school-based interventions (one or more of: school health policy, oral health education, healthy school environment, access to oral health services, community involvement) vs No intervention or usual practice/activities
Dental caries measured by net increment in DMFS scores · Primary school children (aged 3-16 years) attending primary school in low- and middle-income countries (LMICs) · Post-intervention; follow-up varied across studies (interventions ranged from <2 years to >=2 years and longer), Intervention type: other (daily tooth brushing)
Effectiveness of primary school-based interventions in improving oral health of children in low- and… (2022)
SMD -1.23 [-1.46, -1.00]1 studyUngraded
Baby-led weaning (BLW) vs Other models of complementary feeding
Overweight/obesity risk · Healthy children aged 6–24 months in Western industrialized countries · 18–78 months, BLW observational studies
Complementary Feeding Caregivers' Practices and Growth, Risk of Overweight/Obesity, and Other… (2022)
OR 0.37 [0.25, 0.55]3 studies · 969 participantsVery low
Food and nonalcoholic beverage marketing (exposure) vs No, less, or less powerful food marketing
Food intake · Children and adolescents aged 0-19 years · Immediate/short-term (post-exposure), Randomized trials
Association of Food and Nonalcoholic Beverage Marketing With Children and Adolescents' Eating Behaviors and… (2022)
SMD 0.20 [0.10, 0.30]30 studies · 2908 participantsModerate
Primary school-based interventions (one or more of: school health policy, oral health education, healthy school environment, access to oral health services, community involvement) vs No intervention or usual practice/activities
Dental caries measured by DMFT scores · Primary school children (aged 3-16 years) attending primary school in low- and middle-income countries (LMICs) · >=2 years, Intervention duration >=2 years
Effectiveness of primary school-based interventions in improving oral health of children in low- and… (2022)
SMD -0.49 [-0.79, -0.19]4 studiesUngraded