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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. 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
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 · Sao Tome (Africa), Country: Sao Tome
Prevalence of dental caries in the permanent dentition amongst 12-year-olds in Africa: a systematic review… (2022)
MEAN 1.63 [1.509, 1.747]1 studyUngraded
Responsive complementary feeding (RCF) / other caregivers' feeding practices vs Other models of complementary feeding (traditional/non-responsive CF)
Dental caries (later in life) · Healthy, term-born, normal-birth-weight infants aged 4-24 months (breastfed and/or formula-fed) in Western… · Later in life, Outpatient care in Western industrialized (European/Anglo-Saxon) countries
Complementary Feeding Caregivers' Practices and Growth, Risk of Overweight/Obesity, and Other… (2022)
No studies on the influence of caregivers' feeding practices during complementary feeding on dental caries later in life were identified.0 studiesNo studies
Study-specific random forest classifier vs Caries versus healthy disease-state labels
Study-specific disease-state discrimination · Oral microbiome samples in 15 case-controlled studies · Human oral samples
Meta-analysis of caries microbiome studies can improve upon disease prediction outcomes. (2022)
no estimate extracted15 studiesUngraded
Chlorhexidine (CHX) vs Cetylpyridinium chloride (CPC)
Reduction in level of contamination by particles >5 um (droplets) at <2 m from patient's oral cavity · Dental patients undergoing aerosol-generating procedures (AGPs) and the dental healthcare providers treating them · cold CHX vs cold CPC; operator level
Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental… (2022) · Cochrane
MD 4.43 [-2.27, 11.13]2 studies · 50 participantsVery low
Machine-learning algorithms for dental caries detection vs Different machine-learning algorithms for caries prediction
Molar caries detection accuracy · Dental images of human beings · Korea, Lee et al., 2018; CNN
Uses of Different Machine Learning Algorithms for Diagnosis of Dental Caries. (2022)
Accuracy 891 study · 3000 participantsUngraded
Traditional screening (referral card given if the inspecting dentist judges the child needs to see a dentist) vs No screening
Cost effectiveness · School children (aged 4 to 15 years), primary and secondary schools in the UK and India
School dental screening programmes for oral health (2022) · Cochrane
As none of the studies reported cost-effectiveness, we could not assess the cost-benefit aspect of school dental screening.0 studiesNo studies
Intervention NR
Caries experience - % dft (descriptive), primary dentition · CL/P vs no CL/P; Table 4 (1 group/1 study)
Caries in children with and without orofacial clefting: A systematic review and meta-analysis. (2022)
% dft CL/P 7.4 vs no CL/P 8.11 studyUngraded
Alvogyl 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 -17.64 [-18.76, -16.52]1 study · 78 participantsUngraded
Imaging (analog or digital radiographs) 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) · General dental practice; in vitro (extracted teeth) and in vivo (clinical) studies, Analysis 2: network meta-analysis (all studies evaluating >=2 index tests)
Enamel Caries Detection and Diagnosis: An Analysis of Systematic Reviews. (2022)
Sensitivity 0.50 [0.40, 0.59]64 studies · 24567 participantsLow
Glass ionomer-based sealant vs Resin-based sealant (fluoride-releasing or non-fluoride-releasing)
Adverse events · 'Healthy' children with caries-free second primary molars, aged 3-5 years (schools and kindergartens, India and China)
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
1 study reported adverse events as some discomfort such as nausea; 1 child experienced a strong gag reflex following the glass ionomer-based sealant while 8 children reported feeling uncomfortable after the fluoride…1 study · 100 participantsVery low
Composite strip crown (CSC) with a post (microhybrid composite resin, Amelogen) vs Post type: composite post (CP) vs fibre post (FP) vs reverse metal post (RMP)
Treatment failure (annual failure rate) · Children with severely decayed maxillary primary incisors treated by pulpectomy (non-vital pulp therapy) · 1 year, University, Iran (Eshghi et al. 2013), Reverse metal post (RMP) arm
Clinical effectiveness of restorative materials for the restoration of carious lesions in pulp treated… (2022)
AFR 01 study · 54 participantsUngraded
Tempered chlorhexidine vs Non-tempered chlorhexidine
Reduction in level of contamination by particles >5 um (droplets) at <2 m from patient's oral cavity · Dental patients undergoing aerosol-generating procedures (AGPs) and the dental healthcare providers treating them · operator level
Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental… (2022) · Cochrane
MD -15.8 [-22.67, -8.93]1 study · 20 participantsVery low
Fluoride-containing dental care products, primarily toothpaste vs Dietary fluoride sources in poor-fluoridated areas
Contribution to total daily fluoride intake · Adults · Multiple countries, Poor fluoride in water (<0.3 mg/L)
Fluoride Intake Through Dental Care Products: A Systematic Review. (2022)
Mean percentage contribution 121 studyUngraded
Caries assessment at enamel threshold vs None
Caries experience · European adolescents aged 16 years · Europe, Exact age
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
Mean DMFS 3.29 [2.49, 4.36]1 studyUngraded
Periodontal treatment (subgingival instrumentation, with or without antimicrobials/surgery) vs No active intervention/usual care
Cost implications · 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
Included studies did not report cost data. A brief economic commentary drew on four external economic evaluations (Smits 2020, Nasseh 2017, Choi 2020, Soloweij-Wedderburn 2017) suggesting potential cost…0 studiesNo studies
Pulpotomy (partial or full) vs None (single-arm pooled success proportion)
Clinical and radiographic success rate (>=6 months) · Human permanent teeth with symptomatic irreversible pulpitis due to carious pulp exposure · >=6 months, Clinical (endodontic/dental), Symptomatic irreversible pulpitis
Outcome of pulpotomy in permanent teeth with irreversible pulpitis: a systematic review and meta-analysis. (2022)
Proportion 0.84 [0.72, 0.92]9 studiesUngraded
Periodontal treatment (subgingival instrumentation, with or without antimicrobials/surgery) vs No active intervention/usual care
Clinical attachment level (CAL) · 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 -0.48 [-0.65, -0.31]18 studiesUngraded
Enamel caries in primary dentition (at 5 years) vs Caries-free primary dentition
Dentinal caries in permanent (newly erupted) teeth · School children and adolescents (6-18 years) followed from primary dentition (baseline examination before 72 months of… · 7-year follow-up, Cohort study, Norway (Saethre-Sundli 2020), Enamel caries in primary dentition
Does Early Childhood Caries Increase Caries Development among School Children and Adolescents? A Systematic… (2022)
OR 1.6 [1.2, 2.0]1 study · 3282 participantsUngraded
Machine-learning algorithms for dental caries detection vs Different machine-learning algorithms for caries prediction
Occlusal caries detection accuracy · Dental images of human beings · Switzerland, Casalegno et al., 2018; CNN
Uses of Different Machine Learning Algorithms for Diagnosis of Dental Caries. (2022)
Accuracy 83.61 study · 217 participantsUngraded
Referral letter based on the common-sense model (CSM) of self-regulation plus dental information guide (DIG) vs Standard referral letter
Proportion of children with treated/untreated caries (receipt of dental care) · School children, primary schools in the USA · mean 8 months
School dental screening programmes for oral health (2022) · Cochrane
OR 1.26 [0.82, 1.93]1 study · 395 participantsVery low
Cognitive behavioural therapy (CBT) vs Usual care, waiting list or no treatment (control)
Additional physical symptoms · People aged 12 years and over with painful TMD lasting 3 months or longer
Psychological therapies for temporomandibular disorders (TMDs) (2022) · Cochrane
This outcome was not measured for this comparison.NRNo studies
Common genetic variants genome-wide (GWAS; ~3.9 million SNPs with MAF > 5%) vs ECC-unaffected children (per-allele case-control association)
Early childhood caries (ECC) - association at lead SNP rs74470773 (3:33958083; nearest gene(s) PDCD6IP) · Children up to age 5-6 years (European / European non-Hispanic ancestry); 843 ECC-affected vs 2124 unaffected across 5… · Cross-sectional (ECC ascertained at the last dental exam before age 6), Population/community child cohorts: rural Appalachia (West Virginia, Pennsylvania) and Iowa (USA) and South West England; European / European non-Hispanic ancestry only, rs74470773 (3:33958083); effect/non-effect allele T/C; MAF 0.47; direction across 5 cohorts -----
Association of Early Childhood Caries with Bitter Taste Receptors: A Meta-Analysis of Genome-Wide… (2022)
Z-score (Stouffer's combined Z, 5 cohorts) -4.5895 studies · 2974 participantsUngraded
Machine-learning algorithms for dental caries detection vs Different machine-learning algorithms for caries prediction
Occlusal caries detection accuracy · Dental images of human beings · in-vitro dental images, Moutselos et al., 2019; MASK R-CNN; most common class
Uses of Different Machine Learning Algorithms for Diagnosis of Dental Caries. (2022)
Accuracy 88.91 study · 88 participantsUngraded
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 · African urban settings, Setting: Urban
Prevalence of dental caries in the permanent dentition amongst 12-year-olds in Africa: a systematic review… (2022)
Prevalence 0.403 [0.233, 0.574]7 studiesUngraded
Dental examinations at three-month intervals and preventive treatments vs Standard care
MRONJ (incidence rate: cases per patient-year) · Men with metastatic prostate cancer receiving intravenous zoledronic acid (at risk of MRONJ) · mean 28.8 months
Interventions for managing medication‐related osteonecrosis of the jaw (2022) · Cochrane
rate ratio 0.18 [0.04, 0.74]1 study · 253 participantsVery low
HVGIC Vitro Molar vs HVGIC Ketac Molar Easymix
Restoration failure · Children with carious primary teeth · 4 years, University, ART; Class I
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) Vitro Molar 3.5%; Ketac Molar Easymix 5.8%1 study · 25 participantsUngraded
Antiretroviral therapy (any, including cART) vs No antiretroviral medication (treatment-naive)
Dental caries experience · Children and adolescents (<18 years) living with HIV (CLWH) · Hospitals and AIDS outpatient centres in India, Brazil, and several Asian countries
Impact of Antiretroviral Therapy on Oral Health among Children Living with HIV: A Systematic Review and… (2022)
OR 0.91 [0.5, 1.65]2 studies · 301 participantsVery low
Glass ionomer-based sealant vs No sealant
Progression of non-cavitated enamel caries · Children with caries-free primary first molars (with or without caries on other teeth), aged 1-5 years (paediatric…
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
No studies reported this outcome.0 studiesNo studies
Intervention NR
Difference in summary specificity (NMA, Analysis 2) · Fluorescence vs Visual
Enamel Caries Detection and Diagnosis: An Analysis of Systematic Reviews. (2022)
Specificity difference (95% CrI) 0.02 [-0.07, 0.11]NRUngraded
Combined antiretroviral therapy (cART) vs Monotherapy or dual antiretroviral therapy
Persistent parotid enlargement prevalence · Children and adolescents (<18 years) living with HIV (CLWH) · Hospitals and AIDS outpatient centres in India, Brazil, and several Asian countries
Impact of Antiretroviral Therapy on Oral Health among Children Living with HIV: A Systematic Review and… (2022)
No significant difference in persistent parotid enlargement between CLWH on cART and those on monotherapy or dual therapy (no numeric estimate reported in the text); 1 study(ies).1 studyVery low
Sugary drinks/sweets consumption vs Children without dental caries
Dental caries (association with sugary drinks/sweets consumption) · Children (deciduous and/or permanent dentition) in low- and middle-income countries · Low- and middle-income countries (Brazil, Nigeria, Cambodia, Tanzania, Mexico, Ethiopia)
Individual, Family, and Socioeconomic Contributors to Dental Caries in Children from Low- and Middle-Income… (2022)
OR 2.04 [1.59, 2.60]7 studies · 3653 participantsUngraded
Machine-learning algorithms for dental caries detection vs Different machine-learning algorithms for caries prediction
Occlusal caries detection accuracy · Dental images of human beings · in-vitro dental images, Moutselos et al., 2019; MASK R-CNN; center pixel class
Uses of Different Machine Learning Algorithms for Diagnosis of Dental Caries. (2022)
Accuracy 77.81 study · 88 participantsUngraded
Amalgam (A) vs Preformed metal crown (PMC)
Treatment failure (annual failure rate) · Children with carious primary molars treated by pulpotomy (vital pulp therapy) · 1 year, University, Turkey (Sonmez and Duruturk 2010), Preformed metal crown (PMC) arm
Clinical effectiveness of restorative materials for the restoration of carious lesions in pulp treated… (2022)
AFR 2.41 study · 83 participantsUngraded
Fluoride-releasing resin-based sealant vs No sealant (no treatment)
Progression of non-cavitated enamel caries · Children with caries-free or non-cavitated carious lesion primary molars, aged 3-7 years (paediatric department,…
Sealants for preventing dental caries in primary teeth (2022) · Cochrane
No studies reported this outcome.0 studiesNo studies
Platelet rich plasma 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
No adverse events were reported in these two trials.2 studiesUngraded
HVGIC bilayer insertion and surface coating protocols vs Alternative HVGIC insertion and surface coating protocols
Restoration failure · Children with carious primary teeth · 3 years, School setting, ART; Class II
Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022)
Annual failure rate (%) 32.4%, 13.7%, 18.7%, 13.4% by insertion/coating arm1 study · 208 participantsUngraded
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 · Malawi (Africa), Country: Malawi
Prevalence of dental caries in the permanent dentition amongst 12-year-olds in Africa: a systematic review… (2022)
Prevalence 0.19 [0.168, 0.214]1 studyUngraded
Scaling and root planing (SRP) plus antibiotics (amoxicillin and metronidazole) vs Supragingival scaling (plus placebo)
Fibrinogen · People with periodontitis and metabolic syndrome (no CVD; primary prevention) · 12 months
Periodontal therapy for primary or secondary prevention of cardiovascular disease in people with periodontitis (2022) · Cochrane
beta coefficient 10.9 [-12.0, 33.8]1 studyVery low
Living with HIV and undergoing antiretroviral therapy (ART/HAART) vs Healthy HIV-negative controls
Dental caries severity (median DMFT/dmft/DMFS/dmfs) · Children and adolescents (<18 years) · Cross-sectional (case-control; single time point), HIV pediatric/ART clinics, AIDS centers, and hospitals in Brazil, India, Saudi Arabia, and West Africa (Cote d'Ivoire, Mali, Senegal)
Oral Health Status of Children and Adolescents Living with HIV Undergoing Antiretroviral Therapy: A… (2022)
Rajonson 2017 reported significantly higher median DMFT/dmft/DMFS/dmfs among CLWH than uninfected children below 12 years; no pooled effect estimate reported.1 studyUngraded
Glucocorticosteroid antibiotic agent (intrasocket) vs Normal saline
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
OR (exact) 0 [0, 2.42]1 study · 19 participantsUngraded
Single-visit root canal treatment vs Multiple-visit root canal treatment (two or more visits)
Radiological failure (periapical radiolucency) after at least 1 year · People aged 10 years or above requiring root canal treatment; permanent teeth with completely formed apex and without… · At least 1 year (range 1 to 5 years)
Single versus multiple visits for endodontic treatment of permanent teeth (2022) · Cochrane
RR 0.93 [0.81, 1.07]13 studies · 1505 participantsModerate
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 · Europe (community, subnational and national dental surveys), Region: non-Scandinavian
Dental caries at enamel and dentine level among European adolescents - a systematic review and meta-analysis. (2022)
MEAN 8.89 [6.41, 12.33]6 studiesUngraded
Cleft lip and/or palate (CL/P) vs No cleft lip and/or palate (non-CL/P)
Restorative index (RI = f/[d+f]) in the primary dentition · Children in the primary dentition with non-syndromic cleft lip and/or palate (CL/P) and comparable children without CL/P · Children with CL/P and comparable non-CL/P children across 12 countries (India, Brazil, China, Sweden, UK, USA, Germany, Greece, Ireland, Netherlands, Jordan, Thailand); studies published 1989-2021
Caries in children with and without orofacial clefting: A systematic review and meta-analysis. (2022)
Of the five studies for which the RI could be calculated, three of them (Dahllof 1989; Nagappan 2019; Veiga 2016) showed a lower RI for children with CL/P compared to children with no CL/P demonstrating a lower…5 studiesUngraded
Imaging (analog or digital radiographs) vs Reference standard (histology, operative excavation, or enhanced visual examination)
Specificity for detecting enamel caries · Asymptomatic children or adults suspected of enamel caries (clinical studies); extracted teeth (in vitro studies) · General dental practice; in vitro (extracted teeth) and in vivo (clinical) studies, Analysis 1: fully within-person comparison (studies evaluating >=3 index tests)
Enamel Caries Detection and Diagnosis: An Analysis of Systematic Reviews. (2022)
Specificity 0.92 [0.84, 0.96]19 studies · 2849 participantsUngraded
Cognitive behavioural therapy (CBT) vs Alternative (active) treatment (e.g. oral splint, medication, self-care or disease management)
Psychological distress at treatment completion · People aged 12 years and over with painful TMD lasting 3 months or longer · Treatment completion
Psychological therapies for temporomandibular disorders (TMDs) (2022) · Cochrane
SMD -0.32 [-0.50, -0.15]6 studies · 553 participantsLow
Antibiotic prophylaxis before dental procedure vs No antibiotic prophylaxis or placebo
Development of endocarditis (in those with definite indication for prophylaxis) · Adults or children at increased risk of bacterial endocarditis (pre-existing cardiac condition) undergoing an invasive… · within 180 days, Definite indication for prophylaxis
Antibiotic prophylaxis for preventing bacterial endocarditis following dental procedures (2022) · Cochrane
OR 1.62 [0.57, 4.57]1 study · 248 participantsVery low
Criteria-based screening with specific (personalised) referral letter vs Criteria-based screening with non-specific referral letter
Dental attendance at general dentist · School children, secondary school in the UK (aged 11 to 13 years) · mean 8 months
School dental screening programmes for oral health (2022) · Cochrane
RR 1.39 [1.09, 1.77]1 study · 201 participantsVery 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 · Malawi (Africa), Country: Malawi
Prevalence of dental caries in the permanent dentition amongst 12-year-olds in Africa: a systematic review… (2022)
MEAN 0.67 [0.631, 0.709]1 studyUngraded
Full-mouth scaling (FMS): scaling/root planing (subgingival instrumentation) of all quadrants within 24 hours, without antiseptic vs Quadrant scaling and root planing (control): SRP of each quadrant in separate sessions at least one week apart
Tooth loss · Adults with a clinical diagnosis of (chronic) periodontitis (1999 classification); studies of aggressive…
Full‐mouth treatment modalities (within 24 hours) for periodontitis in adults (2022) · Cochrane
Tooth loss: None of the studies comparing FMS vs control reported tooth loss.0 studiesNo studies
Selective (partial, one-step) removal of carious tissue vs Non-selective (complete) caries removal to hard dentine
Pulpal disease (signs/symptoms of pulp necrosis) · Children with dentine caries in primary and permanent teeth · 12 months, 3 studies (primary and permanent teeth)
Minimal intervention dentistry for managing carious lesions into dentine in primary teeth: an umbrella review. (2022)
RR 0.27 [0.05, 1.60]3 studiesUngraded