Effects of the National Health Service Corps expansion on dental care use in underserved areas

The National Health Service Corps (NHSC) expanded substantially from 2009 through 2010 to increase dental workforce supply in dental Health Professional Shortage Areas (HPSAs). However, to the authors' knowledge, no past studies have empirically examined the expansion's impact on dental care use.

The authors used a quasi-experimental difference-in-differences design to compare dental care use among adults residing in counties always designated as whole-county HPSAs (ie, shortage counties) with counties never receiving HPSA designation (ie, nonshortage counties) from 2006 through 2012. Data sources included the Centers for Disease Control and Prevention's Behavioral Risk Factor Surveillance System Selected Metropolitan and Micropolitan Area Risk Trends county data and the Health Resources and Services Administration's Area Health Resources File. The Behavioral Risk Factor Surveillance System adults (n = 401,075) were classified into the following 7 subgroups: insured older adults (ie, ≥ 65 years), insured female non-older adult, insured male non-older adult, insured low-income non-older adult, insured middle-income non-older adult, insured high-income non-older adult, and uninsured non-older adult.

The NHSC expansion was associated with statistically significant increases in any dental care use in the past year among 2 of the 7 subgroups studied: an unadjusted 2.6-percentage point (PP) increase (95% CI, 0.4 to 4.9 PPs) and an adjusted 3.0-PP increase (95% CI, 0.6 to 5.3 PPs) for insured female non-older adults and a 4.6-PP increase (95% CI, 1.1 to 8.1 PPs) with or without adjustment for insured middle-income non-older adults.

The study findings suggest that the 2009-2010 NHSC expansion was associated with increased dental care use for subpopulations with relatively few demand-side barriers.

A supply-side intervention, the NHSC expansion alone was insufficient to improve dental care use for uninsured adults, insured older adults, and insured low-income or insured male non-older adults.