In the study of about 3,000 adults, almost 50 percent were diagnosed with meningioma, a common type of brain tumor attributed to frequent doses of dental x-ray radiation.
These tumors grow in the lining inside the skull. Meningiomas grow slowly and it is rare for them to be cancerous. But, depending on their position in the brain, can still cause serious problems by interfering with speech, vision, personality and movement.
Having more than one dental x-ray a year can double or even triple the chance of developing the brain tumor, according to an American study.
The academe at Yale University School of Medicine in New Haven, Connecticut, and the Brigham and Women’s Hospital in Boston, Massachusetts, looked at two types of head x-ray, called ‘bitewing’ and Panorex.
Those who remembered having bitewing x-rays on at least a yearly basis, were at a 40 to 90 per cent increased the risk.
This is the most common type and is taken while the patient bites on an X-ray film coated in lead and plastic placed at one side of the mouth.
Having one of these X-rays at least once a year raised the odds of the disease by between 40 and 90 per cent, depending on age, the journal Cancer reports.
People who remembered having Panorex examinations once a year or more were 2.7 to 3.0 times more likely, depending on age, to have developed meningioma than those who did not.
This type of X-ray shows all the teeth and is taken by a camera that rotates around the patient’s head.
Researcher and study author Dr. Elizabeth Claus said that much of her data related to x-rays done decades earlier and doses of radiation are lower now than in the past.
Despite this, she advises patients who told her they are to have an x-ray to question their dentist whether it is really necessary.
A brain surgeon at Yale University who carried out the research shared also the same sentiment.
The British Dental Association said that dental x-rays are used more in the US than in the UK and it wouldn’t be normal for someone with healthy diet and healthy mouth to have regular X-rays.
Scientific advisor, Professor Damien Walmsley, said: ‘X-rays are a vital tool in dentistry and reveal problems in the teeth and surrounding bone that simply cannot be observed by the naked eye, and often before patients experience any pain or discomfort.
‘The earlier dental problems are identified, the easier they are to treat.’
Dr. Paul Pharoah, a reader in cancer epidemiology at Cambridge University, said: “The authors report that dental x-rays are associated with a small relative increase in risk of disease of approximately 50 percent or 1.5-fold. This finding is statistically significant.
“However, as the disease is rare, the increase in absolute risk is tiny, the lifetime risk increasing from 15 in every 10,000 people to 22 in 10,000.”
He added, “People who have had dental x-rays do not need to worry about the health risks of those x-rays. Nevertheless, dental x-rays should only be used when there is a clear clinical need in order to prevent unnecessary exposure to ionizing radiation.”