Frequent dental X-rays may significantly increase the risk of non-malignant brain tumours, a new study suggests.
Over a lifetime, having dental X-rays can double or triple the chances of developing meningioma tumours.
However, the likelihood of developing a brain tumour at all is very small.
Meningiomas, which account for about one in five primary brain tumours, affect two or three in every 100,000 people in the UK each year.
The tumours are slow growing, often causing no symptoms, and usually benign.
Researchers found that patients in their study who had meningioma, the brain tumour most commonly diagnosed in the United States, reported having more frequent dental X-rays compared to those in a control group who had never been diagnosed with the disease.
The scientists analysed data from 1,433 patients with meningioma, who were between 20 and 70 years of age and lived in Connecticut, Massachusetts, North Carolina, the San Francisco Bay area and in eight Houston counties.
Data from these patients was compared to a control group of 1,350 people who had never been diagnosed with this type of tumour.
The scientists found that patients with meningioma were more than twice as likely in their lifetime to have had a bitewing X-ray, the kind where a tab is placed between the teeth.
Patients who said they had received a bitewing X-ray either once a year or more frequently were between 1.4 and 1.9 times as likely to be diagnosed with meningioma.
The findings appear in an early online edition of the journal Cancer, published by the American Cancer Society.
While patients are now exposed to less radiation than in the past, ‘the study presents an ideal opportunity in public health to increase awareness regarding the optimal use of dental X-rays, which unlike many risk factors is modifiable’, lead study author Dr Elizabeth Claus, of the Yale University School of Medicine and Boston’s Brigham and Women’s Hospital, said in a statement.
A Department of Health spokesperson said: ‘Patient safety is a priority and the UK has stringent safeguards in place covering the use of dental X-rays. All X-ray exposures must be clinically justified.
‘Radiation protection is a mandatory topic for continuing professional education for dentists and must be undertaken to maintain registration with the General Dental Council.’