Has your child been to the orthodontist this year? Was he or she exposed to dangerous levels of radiation?
According to research reported in the New York Times, more and more dentists and orthodontists are using an imaging device that delivers significantly higher doses of radiation than regular X-rays. While people usually don’t have any immediate problems from such radiation, exposure can be harmful over the long-term and has been linked to an increased risk of developing cancer.
Promoters of the cone-beam CT scanner claim that this technology is a safe way to obtain highly detailed images of a patient’s mouth and skull that can be used to help treat complicated dental problems more accurately. Health experts, however, are concerned about the cumulative effects of radiation from these scans, and think they shouldn’t be used routinely.
For patients with more serious dental issues, such as cases involving implants or impacted teeth, the scanner’s comprehensive images may justify the radiation exposure. But in most cases, traditional X-rays, which expose patients to far lower levels of radiation, provide perfectly adequate images. It is worrisome, therefore, that some orthodontists, apparently misinformed about the risks of these scans, are using the cone-beam technology to scan all patients-many of whom are children.
The use of the cone-beam CT scanner is even more controversial for children, because they are more susceptible to the effects of radiation than fully developed adults. These scans put children at greatest risk for several reasons: they are smaller, their bodies are still developing, and the earlier they begin getting scanned, the more exposure they are likely to have over their lifetime. The main concern is cumulative exposure, not just a single strong dose of radiation.
In addition to the cone-beam scanner, there is also concern about the safety of X-rays taken during annual visits to the dentist. Despite a national campaign to reduce radiation levels to those absolutely necessary for proper imaging, many dental offices are still using outdated X-ray machines that emit more radiation than the newer machines. As evidenced by the cone-beam CT scanner, newer does not, of course, always mean less radiation.
Misuse or overuse of the cone-beam CT scanner also points to a much larger issue that has nothing to do with radiation: the extensive financial relationships that exist between doctors and the companies that make medical products. When manufacturers and doctors get too cozy, conflicts of interest arise, and patient care suffers. The cone beam scanners have become popular, in large part, because the machine’s primary manufacturer, Imaging Sciences International, has paid dentists and orthodontists to promote it. Although these health professionals may endorse the use of this scanner because they truly believe in its benefits, their enthusiasm may be influenced by these payments and the biased information they receive from the companies that make them. After a health professional has received a check, a dinner, or been to a conference at a fancy hotel with all expenses paid, dozens of research studies show that his or her opinion on a given product will probably be more positive than it otherwise would have been.
It is true that each scan only very minimally increases the risk of cancer. Unfortunately, the risk of these scans adds up quickly if every other trip to the orthodontist or dentist requires one. Dentists, orthodontists, patients, and parents need to ask: is this really needed? Especially when the patient is a child and when safer options are available, is the additional exposure to radiation really worth it?
To read more about radiation and how much we are exposed to from the environment, medical imaging and other sources, read our article “Everything you ever wanted to know about radiation, but were afraid to ask.”
 Bogdanich W, Craven McGinty J. Radiation Worries for Children in Dentists’ Chair. The New York Times. 22 November 2010.
 Gonzalez A. Risk of Cancer from Diagnostic X-rays: Estimates for the UK and 14 Other Countries. The Lancet. 2004;363:345-351.