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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.
866 questions in 43 reviews · Oral and maxillofacial surgery
current versionsNo studies 188 · 21.7%Ungraded 548 · 63.3%Very low 81 · 9.4%Low 37 · 4.3%Moderate 8 · 0.9%High 4 · 0.5%
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 |
|---|---|---|---|
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) Postmenopausal osteoporosis with pathological fracture · Postmenopausal women (European ancestry) · Lifelong genetic liability, MVMR (IVW), adjusted for DMFS From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.016 [0.867, 1.191] | 281786 participants | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Forearm fracture · European GWAS participants · SVMR Weighted Median From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.914 [0.799, 1.046] | 490889 participants | Ungraded |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) 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 1.126 [0.975, 1.300] | 489106 participants | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Osteoporosis · European GWAS participants · SVMR Weighted Median From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.002 [0.925, 1.086] | 483725 participants | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Lumbar spine bone mineral density (BMD) · Females (all ages) · Long-term / lifetime fluoride exposure, Females, low-to-moderate risk-of-bias studies: 0.20 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | MD 0.02 [-0.02, 0.07] | NR | Ungraded |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) Osteoporosis · 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 0.998 [0.933, 1.067] | 483725 participants | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS, adjusted for periodontitis 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 1.011 [0.876, 1.167] | 376746 participants | Ungraded |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) Osteoporosis · 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 1.156 [0.994, 1.343] | 483725 participants | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of fractures (any site) · General population (both sexes, all ages) · Long-term / lifetime fluoride exposure, Drinking-water fluoride 2.0 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 1.06 [0.80, 1.41] | 4 studies | Ungraded |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Plaque Index (PI) · Individuals assessed for periodontal health (mainly children and adolescents, age >2 years) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | MD 0.29 [0.24, 0.34] | 6 studies · 1618 participants | Low |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Osteoporosis · European GWAS participants · SVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.329 [0.991, 1.782] | 483725 participants | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Postmenopausal osteoporosis with pathological fracture · European GWAS participants · SVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.934 [0.786, 1.111] | 281786 participants | Ungraded |
Genetically predicted periodontitis vs Reference (lower genetically predicted periodontitis liability) Fracture of forearm · 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 0.990 [0.951, 1.031] | 490889 participants | Ungraded |
Genetically predicted dental caries (DMFS index) vs Reference (1-SD lower genetically predicted DMFS) Postmenopausal osteoporosis with pathological fracture · Postmenopausal women (European ancestry) · Lifelong genetic liability, SVMR (IVW), total causal effect From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.343 [0.948, 1.901] | 281786 participants | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of femoral fractures · General population (both sexes, all ages) · Long-term / lifetime fluoride exposure, Drinking-water fluoride 0.5 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 0.86 [0.71, 1.05] | NR | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability Osteoporosis · European GWAS participants · SVMR IVW From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.998 [0.933, 1.067] | 483725 participants | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Osteoporosis with pathological fracture · European GWAS participants · SVMR Maximum Likelihood From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.278 [0.921, 1.773] | 376746 participants | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of wrist fractures · General population (both sexes, all ages) · Long-term / lifetime fluoride exposure, Drinking-water fluoride 0.01 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 1.00 [0.99, 1.01] | NR | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Risk of fragility fractures · Females (all ages) · Long-term / lifetime fluoride exposure, Females: drinking-water fluoride 0.9 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | RR 1.00 [0.79, 1.27] | NR | Ungraded |
Intervention NR Osteoporosis · DMFS, bias-corrected (MR-RAPS/Debiased IVW) From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 1.171 [1.051, 1.304] | NR | Ungraded |
Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability 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 1.055 [0.983, 1.132] | 490700 participants | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Forearm fracture · European GWAS participants · SVMR MR-Egger From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.883 [0.738, 1.057] | 490889 participants | Ungraded |
Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference) Hip/femoral bone mineral density (BMD) · Females (all ages) · Long-term / lifetime fluoride exposure, Females, low-to-moderate risk-of-bias studies: 4.0 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | MD 0.09 [-0.09, 0.27] | NR | Ungraded |
Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS Forearm fracture · European GWAS participants · SVMR Maximum Likelihood From teeth to bone: dental caries has causal effects on osteoporosis and osteoporotic fracture. (2025) | OR 0.920 [0.836, 1.011] | 490889 participants | Ungraded |
Higher drinking-water fluoride concentration vs Null/reference drinking-water fluoride exposure Spine bone mineral density · Females · Females, low-to-moderate risk-of-bias studies: 0.7 to 2.35 mg/L vs null The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. (2025) | MD 0.06 [-0.01, 0.12] | NR | Ungraded |
Age 8-10 years vs Age >10 years Spontaneous space closure · Children and adolescents with maxillary permanent first molar extraction · Follow-up to complete eruption of the permanent second molar, Maxilla Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR >100.00 [0.01, >100.00] | 3 studies | Ungraded |
Occlusal splint vs Another occlusal splint with a different mechanism of action Severity of joint noise · 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 studies | No studies |
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management) Self-reported joint pain when chewing · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 4 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Occlusal splint vs Acupuncture Range of mandibular motion · People with temporomandibular disorders (TMD) · Short term, Myofascial pain TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD 5.54 [-8.06, 19.13] | 2 studies · 67 participants | Ungraded |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Joint pain at rest · People with temporomandibular disorders (TMD) · Short term (10 weeks), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 0.13 [0.02, 0.94] | 1 study · 60 participants | Very low |
Non-syndromic cleft lip and palate (CLP) status and its oral microbiota (exposure/grouping) vs Children and adolescents aged 0-18 years without CLP (controls) Dental caries (proportion of patients with caries) · Children and adolescents aged 0-18 years with non-syndromic cleft lip and palate (CLP) Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | OR 2.03 [1.46, 2.84] | 3 studies · 688 participants | Ungraded |
Intervention NR Periodontopathogenic microbiota composition · Narrative: Campylobacter/Fusobacterium/F. nucleatum/Prevotella intermedia-nigrescens/Parvimonas micra/Porphyromonas gingivalis in CLP Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | no estimate extracted | 6 studies | Ungraded |
Non-syndromic cleft lip and palate (CLP) status and its oral microbiota (exposure/grouping) vs Children and adolescents aged 0-18 years without CLP (controls) Lactobacillus spp. salivary/plaque counts (cariogenic microbiota) · Children and adolescents aged 0-18 years with non-syndromic cleft lip and palate (CLP) Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | For the outcome of the presence of Lactobacillus spp., there were no significant differences between patients with CLP and healthy patients, and the diversity of the studies led to high heterogeneity; however, the p… | NR | Ungraded |
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management) Muscle pain when chewing · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 4 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management) Muscle pain at rest · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 4 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Non-syndromic cleft lip and palate (CLP) status and its oral microbiota (exposure/grouping) vs Children and adolescents aged 0-18 years without CLP (controls) Streptococcus mutans salivary/plaque counts (cariogenic microbiota) · Children and adolescents aged 0-18 years with non-syndromic cleft lip and palate (CLP) Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | Two studies were analyzed that reported the outcome in means of the presence of Streptococcus mutans, and that there was no difference between the means for healthy patients and those with CLP. The results of these… | 2 studies | Ungraded |
Occlusal splint vs Another occlusal splint with a different mechanism of action Recurrence rate · 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 studies | No studies |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Self-reported joint pain when chewing · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 3 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Mandibular third molar present vs Mandibular third molar absent 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 2.28 [1.67, 3.09] | 4 studies · 467 participants | Low |
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), Maxilla Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | Prevalence 85.3 [73.7, 92.3] | 9 studies · 665 participants | Ungraded |
Occlusal splint vs Acupuncture Recurrence rate · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 5 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Occlusal splint vs Pharmacological therapy Recurrence rate · 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 studies | No studies |
Occlusal splint vs Pharmacological therapy Discomfort · 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 studies | No studies |
Occlusal splint vs Pharmacological therapy Severity 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 studies | No studies |
Extraction of a maxillary permanent first molar vs Extraction of a mandibular permanent first molar 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), Overall Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 7.77 [4.99, 12.11] | 9 studies · 1349 participants | Low |
Intervention NR Spontaneous space closure · Mandible: M2 Demirjian E-F vs G-H Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 42.0 | 1 study | Ungraded |
Occlusal splint vs Pharmacological therapy Self-reported joint pain when chewing · People with temporomandibular disorders (TMD) · Short term (3 months), Osteoarthritis Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 2.10 [0.83, 5.30] | 1 study · 29 participants | Very low |
Occlusal splint vs Another occlusal splint with a different mechanism of action Muscle pain when chewing · 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 studies | No studies |
Extraction at patient age 11-12 years vs Extraction at patient age 8-10 years 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 0.82 [0.35, 1.88] | 2 studies | Ungraded |
Extraction at patient age 11-12 years vs Extraction at patient age 8-10 years 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 0.29 [0.11, 0.81] | 2 studies | Ungraded |