"I usually get a hard time from the dentist, like I'm a bad mother or something," she says. "Maybe I'm being silly as a parent. Maybe it's such a minute amount of radiation, but I think, my kid is going to get how many X-rays in his life, and if I can prevent some of them why not do it?"
Maybe she is being silly -- but maybe not. It's impossible to tell, because there are no good studies showing the right number of X-rays to give someone who isn't having any particular dental problem. While some dentists do bitewing X-rays every six months on a healthy patient, others hardly ever do them, relying instead on a visual examination of the mouth with a sharp explorer and a mirror.
It's an important question, since dental X-rays are the only form of medical radiation received on a regular basis by large numbers of American men, women, and children.
Radiation from dental x ray in dentist surgeries and hospitals causes 700 people in Britain to develop cancer each year, researchers say today.
Although medical X-rays help diagnose disease, they have long been known to cause a small increase in the risk of cancer because of the radiation they emit.
X-rays are the largest man-made source of radiation to which the public is exposed, accounting for 14 per cent. Atomic testing and discharges from nuclear power stations account for a fraction of that figure, and most of the rest is natural radiation such as radon from granite rocks.
Researchers from Oxford University (UK) and Cancer Research UK estimated the size of the risk based on the number of X-rays carried out in Britain and in 14 other countries.
According to their findings, published in the medical journal The Lancet, the results showed that X-rays accounted for six out of every 1,000 cases of cancer up to the age of 75, equivalent to 700 out of the 124,000 cases of cancer diagnosed each year.
In the UK, the National Radiological Protection Board (NRPB) has monitored the doses of radiation used in X-ray examinations for more than a decade. Advancing technology has halved the dose used in X-ray examinations since the early 1990s but the board found a 20-fold difference between the doses delivered in different hospitals in its latest review.