Spillover Effects of the Affordable Care Act? Exploring the Impact on Young Adult Dental Insurance Coverage.

Objectives: To assess whether the Affordable Care Act's (ACA) dependent coverage health insurance mandate had a spillover impact on young adult dental insurance coverage and whether any observed effects varied by household income.

Data: Medical Expenditure Panel Surveys from 2006 through 2011.

Study Design: We employed a difference-in-difference regression approach comparing changes in insurance rates for young adults ages 19-25 years to changes in insurance rates for adults ages 27-30 years. Separate regressions were estimated by categories of household income as a percentage of the Federal Poverty Level (FPL) to understand whether the mandate had heterogeneous spillover effects.

Results: Private dental insurance increased by 6.7 percentage points among young adults compared to a control group of 27-30-year olds. Increases were concentrated at middle-income levels (125-400 percent FPL).

Conclusions: The dependent coverage mandate provision of the Affordable Care Act has not only increased health insurance rates among young adults but also dental insurance coverage rates.