Closing the Gap

Tooth decay is entirely preventable, yet more than 40 percent of children have at least one cavity, according to the Centers for Disease Control and Prevention, with poorer and minority kids shouldering a disproportionate burden. For the last two years, Ramya Bhat and Carolyn Ferrick, both D12, have been examining some of the socioeconomic causes at the root of these persistent disparities.

Using extensive health and demographic data from hundreds of children treated at the Children’s National Medical Center in Washington, D.C., and Columbus Children’s Hospital and Cincinnati Children’s Medical Center, both in Ohio, Bhat investigated the reciprocal relationship between body mass and tooth decay, while Ferrick focused on the socioeconomic factors that may influence children’s oral health.

In her study, Bhat followed two groups of children, 454 with cavities and 429 cavity-free, studying what happened to their body mass index (BMI) over 12 months. Previous studies had provided contradictory data. Some researchers found an association between decay and malnutrition, probably because toothaches or missing teeth interfere with eating nutritious foods, while other scientists linked the presence of cavities with obesity, both conditions likely the result of high-fat, high-sugar diets.

Bhat’s data bolstered the latter hypothesis. The cavity-free kids’ BMI remained pretty stable while the BMI of kids with cavities crept up. At the end of a year, Bhat found significant differences between the two groups. What’s more, the more extensive the tooth decay, the greater the increase in BMI. Children with seven or more cavities experienced the greatest change in BMI.

Despite the strength of her data, Bhat doesn’t dismiss the tooth decay-malnutrition hypothesis altogether.

“It’s interesting to see kids could go in two completely different directions,” says Bhat. “There is no clear predictor that shows us why some kids go down one road versus the other. The nutrition data might give us more answers to that.”

Meanwhile, Ferrick tried to tease apart the relationship between early childhood decay and socioeconomic factors, including race, family income, insurance type and family size. These last two factors turn out to have the biggest impact on children’s oral health. More than half of children with extensive decay came from large families, defined as six to 10 members, while the majority of cavity-free children came from families with fewer than four members.

Children with cavities were also more likely to be uninsured than their decay-free counterparts. But perhaps counterintuitively, family income didn’t stand out as a major risk factor for childhood tooth decay.

“It was a little surprising that family income was not as significant a predictor. We can surmise we got that outcome because the study population was generally low income,” Ferrick says.

To prevent childhood tooth decay in this population, Ferrick would like to see oral health education piggy-backed onto existing programs, including the well-child health care often available to uninsured families.

“Children at this age are more likely to be seen by a physician than a dentist,” says Ferrick. “Physicians need to be informed about basic oral care, so they can spread that knowledge to mothers.”

Bhat’s data led her also to conclude that education is the key. “I think dentists providing nutrition advice to parents of their pediatric patients would help, too. There’s such a big overlap on all these topics.”

Bhat and Ferrick presented their findings at the International Association for Dental Research conference last spring.

This story first appeared in the Fall 2011 Tufts Dental Medicine magazine.

Jacqueline Mitchell can be reached at jacqueline.mitchell@tufts.edu.