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Evidence found and GRADE certainty

410 questions · 836 findings · 55 reviews

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No studies found 1 · 0.1%GRADE not reported 794 · 95%Very low 16 · 1.9%Low 12 · 1.4%Moderate 6 · 0.7%High 7 · 0.8%

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Lumbar spine bone mineral density (BMD) · general population

Spine BMD showed an inverted U-shaped association with fluoride (peak ~0.6 mg/L); excluding high risk-of-bias studies gave small positive MDs (e.g., 0.05 g/cm2, 95% CI 0.01-0.10, up to 2.27 mg/L); ungraded.

4 findings from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Sensitivity (excluding high risk-of-bias studies): 1.27 to 2.27 mg/L vs null
    MD 0.05 [0.01, 0.10]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Sensitivity (excluding high risk-of-bias studies): 0.60 mg/L vs null
    MD 0.06 [-0.02, 0.13]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Both sexes, main dose-response
    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)
    Studies not reported
    GRADE not reported
Show 1 more finding
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Sensitivity (excluding high risk-of-bias studies): above 2.27 mg/L vs null
    MD 0.04 [-0.21, 0.30]
    Studies not reported
    GRADE not reported

Higher national income (GNI per capita) vs Lower national income (GNI categories: middle <=$15,000 / high $15,001-25,000 / very high >$25,000)

Odds of higher caries (DMFT) category · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022)

Higher national income was strongly associated with lower odds of poor oral health (OR 0.10, 95% CI 0.03 to 0.37; about 90% lower odds); not GRADE-rated.

1 finding from 1 review

Sugar consumption (higher sugar intake) vs No sugar consumption (lower/no intake)

Early childhood caries (ECC) · Preschool children (<6 years)

Higher sugar consumption is associated with early childhood caries in children under 6 years: pooled OR 1.59 (95% CI 1.50 to 1.68) from 9 cohort studies with no heterogeneity (I2=0%); the body of evidence was not GRADE-rated (ungraded).

1 finding from 1 review

Genetically predicted DMFS (dental caries) vs Reference (1-SD lower genetically predicted DMFS)

Lumbar spine and pelvis fracture · European-ancestry adults

Genetically predicted dental caries (DMFS) had no significant causal effect on fracture of lumbar spine and pelvis (multivariable MR, OR 0.968).

2 findings from 1 review

Genetically predicted DMFS (dental caries) vs Reference (1-SD lower genetically predicted DMFS)

Forearm fracture · European-ancestry adults

Genetically predicted dental caries (DMFS) had no significant causal effect on fracture of forearm (multivariable MR, OR 0.973).

2 findings from 1 review

Replacement of the defective restoration vs Repair of the defective restoration

Composite: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · Dentists managing a defective direct resin composite restoration (posterior occlusal Class I; standardized vignette of a 30-year-old,…

For a defective composite restoration with loss of dental hard substance adjacent to the restoration, surveyed dentists most often preferred repair over replacement (pooled RR 0.75; p = 0.004); ungraded.

1 finding from 1 review

Replacement of the defective restoration vs Repair of the defective restoration

Composite: Preference for replacement over repair - Scenario 5: open margin · Dentists managing a defective direct resin composite restoration (posterior occlusal Class I; standardized vignette of a 30-year-old,…

For a defective composite restoration with open margin, surveyed dentists most often preferred replacement over repair (pooled RR 3.93; p < 0.001); ungraded.

1 finding from 1 review

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Risk of fragility fractures · Females (all ages)

In females, fragility-fracture risk was U-shaped: lowest ~0.4 mg/L, rising above 0.9 mg/L (RR 0.84 at 0.34, 1.00 at 0.9, 1.13 at 1.1 mg/L vs null); ungraded.

3 findings from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females: drinking-water fluoride 1.1 mg/L vs null
    RR 1.13 [0.93, 1.37]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females: drinking-water fluoride 0.34 mg/L vs null
    RR 0.84 [0.67, 1.07]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females: drinking-water fluoride 0.9 mg/L vs null
    RR 1.00 [0.79, 1.27]
    Studies not reported
    GRADE not reported

Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS

Femur fracture · European GWAS participants

The SVMR MR-Egger interval included the null.

3 findings from 1 review

Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability

Osteoporosis with pathological fracture · European-ancestry adults

Genetically predicted periodontitis had no causal effect on osteoporosis with pathological fracture (single-variable MR, OR 1.003).

2 findings from 1 review

Genetically predicted DMFS (dental caries) vs Lower genetically predicted DMFS

Lumbar spine and pelvis fracture · European GWAS participants

The SVMR Weighted Median interval included the null.

3 findings from 1 review

Replacement of the defective restoration vs Repair of the defective restoration

Amalgam: Preference for replacement over repair - Scenario 2: loss of dental hard substance adjacent to the restoration · Dentists managing a defective direct amalgam restoration (posterior occlusal Class I; standardized vignette of a 30-year-old,…

For a defective amalgam restoration with loss of dental hard substance adjacent to the restoration, surveyed dentists most often preferred replacement over repair (pooled RR 4.70; p < 0.001); ungraded.

1 finding from 1 review

Genetically predicted DMFS (dental caries) vs Reference (1-SD lower genetically predicted DMFS)

Postmenopausal osteoporosis with pathological fracture · Postmenopausal women (European ancestry)

In multivariable MR (adjusted for periodontitis), genetically predicted dental caries (DMFS) causally increased postmenopausal osteoporosis with pathological fracture (OR 1.422, moderate evidence).

2 findings from 1 review

Replacement of the defective restoration vs Repair of the defective restoration

Amalgam: Preference for replacement over repair - Scenario 6: corrosion · Dentists managing a defective direct amalgam restoration (posterior occlusal Class I; standardized vignette of a 30-year-old,…

For a defective amalgam restoration with corrosion, surveyed dentists most often preferred replacement over repair (pooled RR 1.59; p < 0.001); ungraded.

1 finding from 1 review

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 30-year-old,…

Subgroup (HDI: Very high): pooled preference was replacement over repair for a defective amalgam restoration with marginal discoloration (RR 6.48); significant HDI variation, p = 0.01.

5 findings from 1 review
Show 2 more findings

Higher national income (GNI per capita) vs Lower national income (GNI categories: middle <=$15,000 / high $15,001-25,000 / very high >$25,000)

Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022)

Mean DMFT in 12-year-olds rises as national income falls: 0.90 (very high income), 2.38 (high income), 3.30 (middle income) (Figure 2); not GRADE-rated.

3 findings from 1 review

Genetically predicted periodontitis vs Without periodontitis (lower genetic liability)

Lacunar stroke · European-ancestry adults

Genetically predicted periodontitis was associated with modestly higher odds of lacunar stroke (OR 1.24); ungraded MR, though the FDR-adjusted P was 0.064 for the primary IVW-FE method (ML-adjusted P 0.037).

1 finding from 1 review

Human Development Index (HDI) vs Higher vs lower HDI categories

Oral health-related quality of life · people aged 60 years and older living in the community

Older adults in higher-HDI countries had better OHRQoL (high 79.9, 95% CI 74.4 to 85.5; very high 78.4, 95% CI 71.1 to 85.8) than those in medium-HDI countries (63.5, 95% CI 54.3 to 72.7); the difference by HDI was statistically significant (ungraded).

3 findings from 1 review

Genetically predicted periodontitis vs Lower genetically predicted periodontitis liability

Lumbar spine and pelvis fracture · European-ancestry adults

Genetically predicted periodontitis had no causal effect on fracture of lumbar spine and pelvis (multivariable MR, OR 1.060).

2 findings from 1 review