CHICAGO (AP) -- Exposure to lead, which is known to cause mental problems and paralysis, may also contribute to cavities.
"It kind of changes the way we think about tooth decay," said Dr. Mark Moss, a dentistry professor at the University of Rochester School of Medicine and Dentistry and author of a study in Wednesday's Journal of the American Medical Association.The finding may explain why poor children are more likely to have tooth decay -- older, rundown homes often have peeling lead paint.
"Right now we're in the 'blame the victim' mode, as if people are bad parents if they don't take care of their children's teeth," Moss said. "But this shows there may be other factors."
Moss and his colleagues studied data from health exams and blood tests on 24,901 patients who participated in a government health survey. The information was from 1988 to 1994 and focused on children 5 to 17.
The researchers adjusted statistically for such things as income, diet and frequency of dental visits.
When the children were divided into three groups according to their lead exposure -- high, medium and low -- the researchers found that nearly 14 percent of tooth decay in children in the highest-level group and 10 percent in the medium-level group could be attributed to lead.
Dr. Jim Crall, who heads the University of Connecticut's pediatric dentistry department, called the findings interesting but far from definitive.
"What I draw from the article is that this is, in fact, one more reason to try to minimize lead exposure in children," Crall said.
Officials at the Centers for Disease Control and Prevention estimate that 57 million private homes in the United States have at least some lead paint, and paint chips are a common source of lead exposure.
Moss said the next step is to understand just how lead might promote tooth decay, something his research did not examine. It is possible, he said, that lead affects salivary gland development.
In a 1997 study that found that baby rats exposed to lead had more tooth decay, the rats had lower production of saliva, which helps clean the teeth.