Expanding public coverage of dental care reduces disparities

Published on March 22, 2022

Dentist examining a female patient's teeth

Regular visits to the dentist can keep our mouths healthy and keep tooth decay and other problems at bay. But studies show that most American adults do not see the dentist regularly. This is especially true for those with limited incomes, a group disproportionately represented by Hispanic and non-Hispanic Black adults. These Americans have significantly higher rates of untreated tooth decay compared to non-Hispanic White adults. These oral health differences, called disparities, have stubbornly persisted over the last 20 years, as recently confirmed in the new NIH report Oral Health in America: Advances and Challenges, a comprehensive overview of the nation’s oral health.

A new analysis, however, offers some hope. A team led by George Wehby, PhD, a professor in health management and policy at the University of Iowa College of Public Health, found that expanding public coverage of dental care was linked to narrowed racial and ethnic disparities in use of dental services. The NIDCR-funded research was published in Health Affairs.

The 2010 passage of the Affordable Care Act (ACA) expanded eligibility for Medicaid, a public health insurance program that assists Americans with limited income. As a result, many people became newly eligible for medical and dental coverage in states that adopted Medicaid expansions in 2014.

To find out if the eligibility changes affected disparities in dental care, the scientists analyzed responses from a nationally representative survey that asks US adults about their health care, including their use of dental services. Among those adults who became newly eligible for Medicaid in 2014 based on income, the researchers compared responses from the three-year period before (2011-2013) and the five-year period after (2014-2018) states broadened eligibility.

Based on survey responses from about 5,700 adults in states that expanded Medicaid eligibility and offered extensive dental benefits (coverage of at least 100 dental procedures), rates of dental visits by Hispanic and non-Hispanic Black adults increased from 14 to 21% and from 20 to 26%, respectively, while rates among non-Hispanic White adults remained unchanged at about 30%. The researchers found a similar narrowing in disparities in these states for use of preventive services like oral exams and teeth cleaning, and for dental treatments like fillings and root canals. But survey responses from a separate group of about 3,500 adults indicated that disparities did not diminish in states that expanded Medicaid coverage yet offered more limited dental benefits.

“Our findings show that expanding eligibility for generous public coverage of dental care makes a difference in increasing use of dental services, and particularly in reducing racial and ethnic disparities,” says Wehby.

Despite the improvements, the authors noted that use of dental services remained low across all three racial and ethnic groups, regardless of states’ expansion status or the extent of dental benefits offered.

“Insurance coverage is only one factor that affects access to care,” Wehby says. “There are many factors that are important for increasing access, enabling adequate use of services, and meeting dental care needs, particularly among low-income populations.”

He and his team are continuing to study the effects of public dental insurance expansions on other oral health-related outcomes.

“This is just a small demonstration of how health services research could provide timely evidence on ways to address social disparities in oral health,” said Wehby.

Source: NIH’s National Institute of Dental and Craniofacial Research