A comprehensive study published in the American Journal of Preventive Medicine (December 2025) reveals that oral health disparities in the United States remained starkly tied to socioeconomic status (SES) between 2011 and 2020. Researchers found that disadvantaged populations consistently experience significantly higher rates of dental caries (cavities) compared to their wealthier, more educated counterparts.
Lead author Dr. Vahan Boyajyan of Drexel University noted that these findings highlight how financial and structural barriers continue to shape the oral health of the nation, suggesting a critical need for public policy reform.
Analysis of the Data
The study analyzed data from 22,855 adults (ages 25+) using the National Health and Nutrition Examination Survey (NHANES). Researchers measured “caries experience” using the DMFT Index (Decayed, Missing, and Filled Teeth).
The researchers evaluated five key socioeconomic markers:
- Income-to-poverty ratio
- Educational attainment
- Health insurance status
- Employment status
- Food security
Key Findings: The “Inequality Gap”
After adjusting for age, sex, and race/ethnicity, the study found that individuals in lower socioeconomic brackets had significantly higher DMFT scores across every category.
| Socioeconomic Factor | Group Compared To | Increase in DMFT Score |
| Education | High School or less vs. College Graduate | +31% |
| Income | Low-income vs. High-income | +27% |
| Education | Some College vs. College Graduate | +19% |
| Employment | Unemployed vs. Full-time Employment | +17% |
| Insurance | Public Insurance vs. Private Insurance | +15% |
| Food Security | Food Insecure vs. Food Secure | +13% |
| Insurance | Uninsured vs. Private Insurance | +9% |
Image by Mohamed Hassan from Pixabay
Significant Disparities
- Education: This was the strongest predictor of poor oral health. Those with a high school diploma or less had a 31% higher rate of caries experience than college graduates.
- Employment: Being unemployed was associated with a 17% increase in DMFT scores compared to full-time workers. Interestingly, part-time workers only saw a negligible 3% increase.
- Insurance: Surprisingly, those with public insurance (15% higher DMFT) fared worse than those with no insurance at all (9% higher DMFT) when compared to the privately insured, potentially highlighting gaps in public dental coverage.
Conclusion and Limitations
While the study provides a robust, nationally representative look at oral health, the authors noted its cross-sectional design means it can identify correlations but cannot definitively prove that low SES causes caries.
The researchers concluded that to improve national oral health, policy must move beyond simple dental check-ups and address the “broader socioeconomic determinants,” such as food security and income inequality.