For people with no dental problems, getting X-rays as part of routine dental checkups might not be a good idea. A new study firms up evidence of a link between frequent dental X-rays and non-cancerous brain tumors.
Meningioma is the most frequently reported primary brain tumor in the United States and, though not cancerous, can cause significant health problems. Dental X-rays are the most common source of exposure to ionizing radiation – a major risk factor for meningioma. Most previous studies of the tumors have focused on people exposed to high levels of radiation from atomic blasts or treatments for cancer or other medical conditions. Only a few studies have looked at lower-dose exposures from dental X-rays, and only in limited numbers of patients.
But this new research, published April 10 in the American Cancer Association journal Cancer, backs up the findings of those previous studies. Researchers looked at more than 1,400 patients from several states who had been diagnosed with meningioma – and more than 1,300 who had not – between 2006 and 2011. Those with brain tumors were more than twice as likely as those without to recall having ever had a bitewing X-ray. And patients who recalled having undergone panorex X-rays – which produce an image of both the upper and lower jaws and teeth – at a young age, on a yearly basis (or more often) were almost five times as likely to have meningioma.
The level of radiation in dental X-rays has declined over the years, but other types of medical imaging involving radiation are on the rise, the study’s authors note. And most of these new procedures expose patients to higher levels of radiation than dental X-rays do. The American Dental Association has also said that there’s little evidence to support using X-rays to search for dental problems in patients without symptoms, or for routinely X-raying patients at pre-set intervals.
“Although dental X-rays are an important tool in well selected patients,” the authors note, “efforts to moderate exposure … are likely to be of benefit to patients and healthcare providers alike.”