Exposure to high amounts of lead is likely one cause of the high rates of tooth decay found among certain groups, such as children raised in the inner city, according to a study in rats by University of Rochester dental researchers published in the September issue of Nature Medicine.
The scientists say that while lead does not actually cause cavities, it appears to make rats -- and thus people, whose teeth get cavities in an identical manner -- much more susceptible.
"This is one more compelling reason to get lead out of the environment," says lead investigator William Bowen, Margaret and Cy Welcher Professor of Dental Research and the founder of the Rochester Caries Research Center, the nation's first research center on tooth decay. Also working on the project were Gene Watson, assistant professor of clinical dentistry; graduate student Bianca Davis; Richard Raubertas, associate professor of biostatistics; and technician Sylvia Pearson.
Lead is well recognized as causing developmental and other problems. While lead has been removed from most gasoline, it's still present in old paint and commonly in soil or dust around contaminated buildings. Bowen says that the areas with the highest lead pollution -- inner cities and the Northeast -- mirror areas where dentists see the highest rates of tooth decay.
The team studied cavity susceptibility in rats born of mothers exposed to lead compared to offspring of rats not exposed to lead and found that offspring from exposed rats had 40 percent more cavities. The study, funded by the National Institute of Dental Research (NIDR), is the first to document the link between lead exposure and high cavity rates that a few small epidemiological studies have suggested.
The team is now searching for the cause. Some studies have
suggested that lead interferes with the development of teeth. In
humans lead is stored in the bones for decades, and higher
amounts than normal are released i
Contact: Tom Rickey
University of Rochester