After years of decline, cavity rates may be inching upward again, according to dental researchers at the annual meeting of the International Association of Dental Research in Washington, D.C.
Ronald Billings, D.D.S., professor of dentistry at the University of Rochester School of Medicine and Dentistry, is presenting results showing that the cavity rate among 10-year-old children in Rochester is on the rise slightly. Billings will speak Saturday, April 8, as part of a symposium that he is helping to lead on "An Agenda for Dental Caries Research in the 21st Century."
Billings' data mirror a trend that has been observed in some European countries, but not yet reported in the United States: The cavity rate among children seems to have bottomed out and in some countries may be rising. That leads to tooth decay among adults, nearly all of whom have at least one cavity. The pain from tooth decay is felt by society in many ways: Annual treatment costs for cavities and their consequences, which are a major cause of sick days in the workplace, are estimated to be as high as $20 billion, researchers at the symposium estimate. Related problems are a leading cause of absence from the workplace.
For his study, Billings drew on data collected by the University's Eastman Dental Center over the last three decades in collaboration with the Monroe County Health Department, which has funded the surveys. Billings and other researchers noted a significant decrease in the cavity rate among children during the 1970s and through the early 1980s. Since then, the decline has flattened, and Billings' latest results show a slight increase in the rate of cavities. The most recent survey shows an average of three cavities per 10-year-old child, up from two cavities per child in the late 1980s.
"The period of significant decline appears to have ended," says Billings. "Among 10 year olds in Rochester, our latest results show a slight increase in the caries rate." ("Caries" is another word for "cavities.")
The cavity rate among children is more than a matter of a little pain and inconvenience. "Cavities beget cavities," says Billings. "People at risk for tooth decay remain at risk for as long as they have teeth. Cavities early in life set in motion a never-ending process of drilling and filling." About one-quarter of children have serious problem with cavities.
Among adults, tooth decay is a serious problem particularly for the elderly, who are as vulnerable as young children to the disease. Many age-related health problems and some medicines cause a dry mouth by creating a lack of saliva. Without the protective benefits of saliva, which helps to neutralize the acids that eat through tooth enamel, many elderly people suddenly find themselves more prone than ever before to cavities. Chronic tooth decay usually results in a number of pulled teeth, bringing on several problems, including limits in food selection, problems in speaking and smiling, and rarely, a serious heart condition caused by the same bacteria that create tooth decay.
"Tooth decay is a bit like heart disease or any number of conditions," says Billings. "You can have a predisposition toward it, but with the proper lifestyle, the risk factors can be moderated substantially. If someone eats a lot of sugar-containing foods and has poor brushing habits, the disease will be present more than if the person didn't undertake those risky behaviors."
Another symposium speaker, William Bowen, will argue that complacency among health-care practitioners, funding agencies, and even dentists and patients is helping to drive the increased rate of cavities.
"Ninety-five percent of adults have cavities. Some people have the idea that the problem has been solved, but that's ridiculous. There is no other disease I know of where it's considered success when 50 percent or more of the population still has the disease," says Bowen, D.D.S., Ph.D., Welcher Professor of Dentistry at the University and an internationally recognized authority on tooth decay. Before joining the University and creating a research center devoted to studying tooth decay, Bowen headed the Caries Prevention and Research Branch of the National Institute for Dental Research.
Dentists attribute the previous decline to widespread water fluoridation, along with more regular preventive dental care. "But for reasons we don't fully understand," says Billings, "now the caries rate appears to be on the increase. It could be a number of things, including poverty, loss of public health funds for school-based prevention programs, and complacence among patients or health-care professionals. The point is, we shouldn't become complacent. We have to continue to look for ways to further reduce or eradicate the problem entirely."
Several other speakers at the symposium will discuss genetic factors that play a role in tooth decay. Researchers around the world are trying to decipher the genes that control or contribute to tooth decay, including genes that affect saliva flow, the composition of saliva, the hardness of tooth enamel, the virulence of the bacteria that inhabit our mouths, and the proteins present in the mouth that welcome or turn back acid-producing bacteria.