Dental X-Rays: Do They Increase Brain Tumor Risk?

As if going to the dentist wasn't painful enough, a new study from Yale suggests a link between frequent dental X-rays and a type of brain tumor.

The study, published this week in the journal Cancer, shows that people who have had frequent dental X-rays are more likely to develop a common brain tumor called meningioma than those who have not, according to CNN.com.

In particular, older patients, who have had higher-radiation X-rays in the past, may be at increased risk, Reuters reported.

The study does not prove that dental X-rays cause tumors, and some dental experts questioned whether the study even shows a link because the results are based on subjects' memory of the frequency of childhood dental X-rays.

The study found that people diagnosed with meningioma who reported having annual dental X-rays (those uncomfortable bite-wings where you hold the film in  place between your teeth) were nearly twice as likely as a healthy control group to have developed those tumors.

People who reported getting a yearly panorex exam -- in which the X-ray is taken outside the mouth and shows all the teeth in one image -- were 2.7 to three times more likely to develop cancer, the study said.

The research was led by Elizabeth Claus of the Yale University School of Medicine, and was based on data from 1,433 patients who were diagnosed with the tumors between the ages of ages 20-79. The average age of the subjects was 57, which means they had greater exposure to older, higher radiation X-rays, Claus said.

Researchers also looked at data from a control group of 1,350 individuals who had similar characteristics, but had not been diagnosed with a meningioma.

Dental patients today are exposed to lower radiation levels than they were in the past, but the research should prompt dentists and patients to re-examine when and why dental X-rays are given, said Claus.

The American Dental Association calls for healthy adults -- meaning without cavities and at low risk of getting cavities -- to get dental X-rays only every two to three years.

While dentists often order X-rays as part of an annual exam, the ADA said in 2006 there was little evidence to back up the routine use of full-mouth dental X-rays in patients without symptoms. The new research raises further questions about the need for such frequent exposure to radiation.

In other health news:

EKGs may help find heart attack risk in seniors. A widely used test to measure electrical activity in the heart may help identify elderly people at risk of a heart attack, said a new study, rekindling a debate over the value of such tests in people without chest pain or other symptoms, according to the Wall Street Journal. In a study involving 2,192 patients 70 to 79 years old without established heart disease, researchers found that abnormalities in an electrocardiogram, or EKG, were associated with a higher risk of heart attacks and other serious heart events over the following eight years.

U.S. seeks voluntary antibiotic limits in livestock. U.S. regulators on Wednesday urged food producers to voluntarily stop using antibiotics in livestock for non-medical uses as part of a broad effort to prevent the rise of drug-resistant "superbugs." The FDA said antibiotics should only be used under the supervision of a veterinarian to prevent or treat illness. It asked companies to start phasing out the use of antibiotics for non-medical purposes, such as promoting growth. The process could take three years, Reuters reported.

Photo credit: wiltondentalassoc.com