"We've come a long way, but a lot more work needs to be done," said lead researcher Dr. Inyang A. Isong, of the Massachusetts General Hospital Center for Child and Adolescent Health Research and Policy in Boston.

Even though black children are less likely to go without dental care than in years past, it's not clear how often they're getting to the dentist, or whether the quality of their care is on par with white kids' care, Isong said in an interview. For their study, she and her colleagues used data from a periodic federal health survey.

Back in 1964, they found, nearly 80 percent of black children and teens had not seen a dentist in the past year. That compared with 48 percent of white kids. By 2010, that figure had fallen to 22 percent among both black and white children.

Similarly, the percentage of black kids who had never seen a dentist fell from 61 percent in 1964 to nine percent in 2010. And again, the racial gap had closed: in 2010, 11 percent of white kids had never seen a dentist, down from 29 percent in 1964.

Why the change? The researchers cannot say for sure, but they suspect public policies explain a large share of it. That includes the creation of Medicaid, the government health insurance program for the poor, and more recent efforts like the Children's Health Insurance Program (CHIP), which was launched in 1997 to help uninsured families whose incomes are not low enough to qualify for Medicaid.

Still, other recent research has found African-American kids are 45 to 67 percent more likely to have untreated cavities than their white peers. It's not clear why that is. But Isong pointed out that her study looked only at percentages of kids who'd been to the dentist ever, or in the past year.

It's possible, she said, that black kids don't go as often as white kids do. (In general, experts say kids should see the dentist every six months.) And it's not known whether the quality of black children's dental care matches that of white children, Isong said.

Under federal regulations, state Medicaid programs must provide kids with dental screenings and treatments, even if a service is not usually covered under the state's program.

"The problem is, in many states that policy isn't adequately enforced," Isong said. In some states, she noted, advocacy groups have filed class-action lawsuits to try to get the Medicaid policy enforced.

There are also other factors that could be at work, according to Isong's team. Black kids may have less-healthy diets or less access to drinking water with added fluoride, for instance. The study focused on the black-white racial divide because there are decades of historical data on that gap. It's only in more recent years that information on other minorities has been collected.

But Isong said other studies show Native American and Hispanic kids - particularly from Mexican families - also have higher rates of cavities and tooth decay than white children. And based on these latest findings, there are plenty of white children not getting basic dental care.

"One in five children in both racial groups are still without a dental visit in the past year," Isong noted. That, she said, points to a need to do better across the board.

"All kids need to be given high-quality, comprehensive dental care," she said.

SOURCE: bit.ly/KYF07t Pediatrics, online July 2, 20012.

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