Full Disclosure is Better than Full-Body Scans

Pretend, for a moment, that you are a dentist.

If you read an article in the Journal of the American Dental Association that tells you that a "cone-beam CR scanner" would provide a safe and effective way to identify tooth and jaw problems earlier and more effectively than older methods like X-rays, you might consider investing in such a gizmo for your office, right?

In fact, there's an entire issue in the JADA dedicated to the wonders of this new technology. Sounds even better, right?

Now ... what if I tell you that the entire issue is underwritten by a cone-beam scanner manufacturer. Still as interested?

I thought not.

Today's New York Times has a long article by Walt Bogdanich and Jo Craven McGinty on this new technology, and about concerns that children, who are particularly vulnerable to the pernicious effects of radiation, are being exposed to excessive levels of radiation in their dentists' chairs.

Individual scans, properly administered, are not dangerous, but the effects are cumulative, so children (and adults) should not be scanned unless there's a genuine need.

An expert in 3-D technology like the cone-beam scan is quoted as saying that "a cone-beam scan produces no more radiation than a whole-body scan at the airport," while another expert argues that "cone-beam scanners can be several hundred times as powerful." (Never mind that there are questions being raised about the radiation levels to which frequent travelers may be exposed.)

The real question is, Why are we exposing children and adolescents to radiation if it isn't necessary?

According to the Times, cone-beam CT scans produced "significantly higher" levels of radiation than traditional dental imaging techniques, without sufficient scientific data to prove that it provides better results.

That's not to say that traditional techniques are perfectly safe. Dentists have been advised not to use old, slow "D-speed" X-ray film "because it requires more radiation than faster film". But about 70 percent of dentists are still using D-speed film.

The Times offered its readers an important sidebar: "What Patients Might Want to Ask the Dentist about X-Rays". It is important to know why a particular technique is being recommended, and that a proper lead shield is being used to protect you (or your child) from unnecessary exposure.

But an even more important question to ask might be why obvious conflicts of interest keep getting by us.

At the end of their lengthy article, Bogdanich and McGinty point to the continuing education credits that dentists can earn "by reading about cone-beam technology in a new magazine, Orthodontic Practice - US, and then answering 10 simple questions appended to the end."

The article is credited to Dr. Edward Y. Lin, a Wisconsin orthodontist, who is a strong supporter of cone-beam scanning. That's fine; different dentists certainly have different opinions about the value of the technology, and Dr. Lin said that "the company did not pay him to write the article or to appear in its full-page advertisement in the same issue."

What company would that be? Imaging Sciences, a scanner manufacturer. For whom Dr. Lin has been a paid lecturer.

In other words: How many lectures paid for that article?