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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.
75,239 questions in 5,342 reviews
current versionsNo studies 15,213 · 20.2%Ungraded 10,323 · 13.7%Very low 17,528 · 23.3%Low 17,951 · 23.9%Moderate 11,190 · 14.9%High 3,034 · 4%
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.
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Intervention NR Log diagnostic odds ratio · Imaging modality: Panoramic radiographs Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Log DOR 5.08 [4.15, 6.02] | 8 studies | Ungraded |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) Femoral neck bone mineral density (FN-BMD) · European-ancestry adults · Lifelong genetic liability, SVMR and MVMR (IVW) From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | No causal effect of oral diseases on FN-BMD was found (SVMR and MVMR); no numeric estimate reported in text (see Fig. 3). | 32735 participants | Ungraded |
Hall technique vs Sealing Treatment success (caries lesion arrest or restoration survival) · Children (aged 3-11 y) with cavitated caries lesions in primary teeth · 6 months, 6-month follow-up Comparative success of minimally invasive treatments for cavitated caries in primary teeth: a network… (2025) | OR 90.71 [1.57, 5243.63] | 44 studies | Moderate |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) Osteoporosis with pathological fracture · European-ancestry adults · Lifelong genetic liability, MVMR (IVW), adjusted for DMFS From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.003 [0.546, 1.842] | 376746 participants | Ungraded |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) Femoral neck bone mineral density (FN-BMD) · European-ancestry adults · Lifelong genetic liability, SVMR and MVMR (IVW) From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | No causal effect of oral diseases on FN-BMD was found (SVMR and MVMR); no numeric estimate reported in text (see Fig. 3). | 32735 participants | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 5: open margin · Coverage: Covering cost of minimally invasive treatment Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 3.09 [1.65, 5.79] | NR | Ungraded |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) Fracture of femur · European-ancestry adults · Lifelong genetic liability, MVMR (IVW), adjusted for DMFS From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.034 [0.963, 1.109] | 489106 participants | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Lumbar spine bone mineral density · European GWAS participants · SVMR IVW From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | BETA 0.105 [0.006, 0.205] | 28498 participants | Ungraded |
Caries-active status (presence of dental caries) vs Caries-free status Relative abundance of S. mutans in saliva · Systemically healthy individuals (children and adults, aged 40 months to 50 years) assessed for dental caries · Cross-sectional, Saliva sample Streptococcus mutans and Caries: A Systematic Review and Meta-Analysis. (2025) | SMD 1.48 [0.45, 2.50] | 5 studies · 258 participants | Ungraded |
Anticaries vaccine or antibody (DNA, recombinant protein, nanoparticle-adjuvanted, live-vector, plant-based, or passive IgY immunization) targeting S. mutans vs Control (unvaccinated / empty vector / PBS / placebo animals) Serum IgG antibody response (immunogenicity) · Animal caries models (mice, rats, hamsters) challenged/colonized with Streptococcus mutans; one transgenic-plant… Assessing the Efficacy and Immunogenicity of Anticaries Vaccine-A Systematic Review and Meta-Analysis. (2025) | no estimate extracted | NR | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · HDI: Low Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 25.94 [1.88, 358.26] | 2 studies | Ungraded |
All European countries pooled (overall) vs None (overall pooled prevalence) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), Overall Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 2.10 [1.63, 2.57] | 34 studies · 493360 participants | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Hip/femoral bone mineral density (BMD) · General population (both sexes, all ages) · Long-term / lifetime fluoride exposure, Both sexes, main dose-response The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | Hip BMD increased in both sexes, linearly in males and non-linearly (starting above 1.2 mg/L) in females (no numeric MD reported in text for main analysis) | NR | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · HDI: Very high Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.87 [1.32, 2.64] | 10 studies | Ungraded |
Older child age (months) vs Younger age (reference) Early childhood caries (ECC) · Children aged 0-5 years in North Africa · 48-59 months Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 2.602 [1.122, 2.302] | 1 study | Ungraded |
Gamified oral health interventions (mobile apps, serious games, augmented reality, game-based education) vs Conventional or traditional oral health education, or non-gamified interventions (comparator varied; several studies were single-arm/uncontrolled) Oral health knowledge · Children and adolescents aged <=18 years · Post-intervention (predominantly short-term; long-term follow-up in a minority of studies) The Application of Gamification in Children's Oral Health Management: Systematic Review. (2025) | The effectiveness of digital-based interventions was generally positive, with 38% (9/24) of the experimental studies reporting improvements in oral health knowledge and behaviors; game-based teaching significantly… | 9 studies | Ungraded |
Intervention NR Sensitivity (trim-and-fill adjusted for publication bias) · Overall; trim-and-fill (20 observed + 6 imputed studies) Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Sensitivity 0.818 [0.778, 0.858] | 26 studies | Ungraded |
Conventional restoration vs Atraumatic restorative treatment (ART) Treatment success (caries lesion arrest or restoration survival) · Children (aged 3-11 y) with cavitated caries lesions in primary teeth · 6 months, 6-month follow-up Comparative success of minimally invasive treatments for cavitated caries in primary teeth: a network… (2025) | OR 2.67 [1.24, 6.15] | 44 studies | Moderate |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 3: secondary caries · HDI: Very high Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 6.56 [4.37, 9.86] | 10 studies | Ungraded |
Timing of first dental visit vs Reference visit timing Early childhood caries (ECC) · Children aged 0-5 years in North Africa · Early visit Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 0.042 [0.013, 0.136] | 1 study | Ungraded |
E-cigarette use (electronic nicotine delivery systems / vaping) vs Traditional (conventional) cigarette smokers Plaque index / periodontal health (relative harm vs conventional smoking) · Adult e-cigarette (ENDS) users (general oral health) An Umbrella Review of E-Cigarettes' Impact on Oral Microbiota and Biofilm Buildup. (2025) | Narrative synthesis: plaque accumulation and periodontal harm were less pronounced in e-cigarette users than in traditional cigarette smokers; cigarette smokers had a significantly higher plaque index than e-cigarette… | 4 studies | Ungraded |
Intervention NR Postmenopausal osteoporosis with pathological fracture · DMFS, bias-corrected (MR-RAPS/Debiased IVW) From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.401 [1.040, 1.887] | NR | Ungraded |
Simple childhood caries prediction models with at least two predictors vs No competing model Dental caries discrimination (area under the curve) · Children and adolescents (≤18 years) · Validation assessment; prediction horizon not reported Risk prediction models for dental caries in children and adolescents: a systematic review and meta-analysis. (2025) | AUC 0.71 [0.69, 0.72] | 1 study | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · Continent: Europe Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.32 [0.27, 0.37] | 6 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 3: secondary caries · HDI: Medium Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.70 [0.05, 10.26] | 2 studies | Ungraded |
Flavonoids (e.g., quercetin, proanthocyanidin) vs Calcium phosphate agent (e.g., CPP-ACP, Ca/P-PILP, niobophosphate) Immediate (24 h) resin-dentin bond strength (MPa) · Artificial caries-affected dentin (ACAD) in extracted permanent human teeth (in vitro) · 24 h (immediate), Etch-and-Rinse + biological ACAD Biomimetic Remineralization Strategies for Dentin Bond Stability-Systematic Review and Network Meta-Analysis. (2025) | MD -12.771 [-20.538, -5.003] | 0 studies | Moderate |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) Osteoporosis · European-ancestry adults · Lifelong genetic liability, MVMR (IVW), adjusted for DMFS From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.000 [0.937, 1.067] | 483725 participants | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability, adjusted for DMFS Femur fracture · European GWAS participants · MVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.024 [0.960, 1.093] | 489106 participants | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · HDI: Very high Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 19.06 [7.76, 46.80] | 10 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 4: marginal discoloration · Continent: Asia Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 5.71 [3.51, 9.28] | 11 studies | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 6: superficial discoloration · Coverage: Covering cost of minimally invasive treatment Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 0.26 [0.16, 0.41] | NR | Ungraded |
Partial pulpotomy vs Full (complete) pulpotomy Postoperative analgesic use · Mature permanent (molar) teeth with deep caries and symptoms indicative of irreversible pulpitis (spontaneous pain) · Postoperative (up to 1 week) The effectiveness of partial pulpotomy compared with full pulpotomy in managing deep caries in vital… (2025) | Analgesic use recorded in both studies. Jassal: PP 12% vs FP 8%. In one study, significantly fewer patients required analgesics with complete/full pulpotomy (30.6%) than partial pulpotomy (54.5%), and mean analgesic… | 2 studies · 156 participants | Ungraded |
Epilepsy (as exposure/condition) vs Healthy participants without epilepsy (control group) DMFT (permanent teeth) · Adults with epilepsy · Adults Evaluating the DMFT and dmft indices in people with epilepsy: A systematic review and meta-analysis. (2025) | SMD 0.548 [0.223, 0.873] | NR | Ungraded |
Ion-releasing restorations (IRR): RMGIC, HVGIC, GIC, compomer/PMRC, giomer vs Composite resin (CR), including bulk-fill composite Proper anatomic form · Children receiving dental restorations (aged 4-11 years; primary teeth; Class I/II/V cavities) · 1 to 2 years Clinical effectiveness of ion-releasing restorations compared to composite restorations in pediatric dental… (2025) | RR 1.00 [0.99, 1.01] | 8 studies · 1044 participants | High |
Intervention NR Log diagnostic odds ratio · Imaging modality: CBCT Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Log DOR 6.33 [5.95, 6.71] | 1 study | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Sample size <500 Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 48 [39, 58] | 9 studies | Ungraded |
Pulp and periapical diseases vs Without pulp and periapical diseases Lacunar stroke · Adults The contribution of oral infectious diseases in lacunar stroke based on meta-analysis and Mendelian… (2025) | No studies addressing the association between pulp and periapical diseases and LS were identified. | 0 studies | No studies |
Replacement of the defective restoration vs Repair of the defective restoration Amalgam: Preference for replacement over repair - Scenario 4: marginal discoloration · Dentists managing a defective direct amalgam restoration (posterior occlusal Class I; standardized vignette of a… · Not applicable (single time-point survey, June to October 2023), HDI: High Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 7.06 [5.14, 9.69] | 7 studies · 1223 participants | Ungraded |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) Fracture of femur · European-ancestry adults · Lifelong genetic liability, SVMR (IVW), total causal effect From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.044 [0.982, 1.110] | 489106 participants | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Lumbar spine bone mineral density (BMD) · General population (both sexes, all ages) · Long-term / lifetime fluoride exposure, Both sexes, main dose-response The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | Inverted U-shaped association in both males and females, highest value around 0.6 mg/L (no numeric MD reported in text for main analysis) | NR | Ungraded |
Anorexia nervosa (as exposure; diagnosed by DSM-III/III-R/IV/V) vs Healthy individuals without anorexia nervosa (age- and sex-matched controls) Stimulated salivary flow rate · Patients with anorexia nervosa aged >=12 years (mean age ~18.4; entirely female in reported data), general… The influence of anorexia nervosa on oral health and related parameters potentially relevant to orthodontic… (2025) | Stimulated salivary flow rate significantly lower in anorexic patients (Paszynska 2015 Nov 1.20 vs 1.57 ml/min, p=0.005; Paszynska 2018 0.99 vs 1.45 ml/min, p<0.00001); reported narratively, not meta-analyzed | 2 studies · 126 participants | Ungraded |
AI algorithms (predominantly CNN/deep learning) as index test vs Dental expert / visual-tactile clinical assessment (reference standard) Specificity · Patients undergoing dental caries detection on dental images (teeth/surfaces across imaging modalities) · Cross-sectional diagnostic accuracy (index test vs reference standard), Overall (all imaging modalities pooled) Examining the diagnostic accuracy of artificial intelligence for detecting dental caries across a range of… (2025) | Specificity 0.90 [0.85, 0.95] | 20 studies · 29423 participants | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Lumbar spine and pelvis fracture · European GWAS participants · SVMR Maximum Likelihood From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.950 [0.808, 1.117] | 490700 participants | Ungraded |
Genetically predicted dental caries vs Without dental caries (lower genetic liability) Lacunar stroke · European-ancestry adults (GWAS) The contribution of oral infectious diseases in lacunar stroke based on meta-analysis and Mendelian… (2025) | OR 0.92 [0.69, 1.23] | NR | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Lumbar spine and pelvis fracture · European GWAS participants · SVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.036 [0.956, 1.122] | 490700 participants | Ungraded |
Conventional restoration vs Placebo Treatment success (caries lesion arrest or restoration survival) · Children (aged 3-11 y) with cavitated caries lesions in primary teeth · 6 months, 6-month follow-up Comparative success of minimally invasive treatments for cavitated caries in primary teeth: a network… (2025) | OR 44.66 [3.22, 620.47] | 44 studies | Moderate |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 3: secondary caries · HDI: Medium Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 5.73 [2.83, 11.57] | 2 studies | Ungraded |
Intervention NR Amalgam: Preference for replacement over repair - Scenario 8: disruption of occlusal integrity · HDI: High Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 1.85 [1.43, 2.39] | 7 studies | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability, adjusted for DMFS Postmenopausal osteoporosis with pathological fracture · European GWAS participants · MVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.012 [0.858, 1.193] | 281786 participants | Ungraded |
Intervention NR Composite: Preference for replacement over repair - Scenario 7: non-stable (mobile) restoration · Coverage: Not covering Clinical Decision-Making of Repair vs. Replacement of Defective Direct Dental Restorations: A Multinational… (2025) | RR 10.96 [6.53, 18.39] | NR | Ungraded |