Are Routine Dental X-rays Dangerous?

On this week’s “health headlines” podcast I discuss a provocative case-control study that suggests that the more dental x-rays people get (especially when under 10 years old), there is a higher risk of a common brain cancer called a meningioma. The American Cancer Society covered this issue quite well last week; here is an excerpt:

X-rays are a source of ionizing radiation, which is a potential risk factor for meningioma. Some of the participants in the study received their x-rays many years ago, when radiation exposure from dental x-rays was much higher than it is with new technology today.

Dental x-ray risk of meningiomaThe study has some drawbacks that make the link between dental x-rays and meningiomas far from certain. Perhaps most importantly, it relied on participants’ memories about their history of dental x-rays (rather than on dental records themselves). Such studies are subject to a phenomenon that scientists call “recall bias,” when people with a disease may be more likely to look for a cause. This might have caused the meningioma patients in the Cancer study to over-report the number of dental x-rays they received, which could have contributed to the findings. Because of this, the study results can only be considered suggestive of a possible link, and more rigorous studies would be needed to prove it.

Otis W. Brawley, M.D., chief medical officer of the American Cancer Society said, “We need more data before we can even begin to state there is a relationship between dental x-rays and these tumors. Until that research is done, the best advice we can give people is to get dental x-rays when they are necessary and only when they are necessary. The dose of radiation given in a bitewing or panoramic x-ray is lower today than it was two decades ago. Nonetheless, x-rays should be done only when necessary. This is true of all x-ray technology, and it’s the same advice experts would have given without this study.”

On its Web site, the American Dental Association responded to the study with a statement that said in part, “The ADA’s long-standing position is that dentists should order dental X-rays for patients only when necessary for diagnosis and treatment.” The statement also encouraged patients to talk to their dentists if they have questions about their dental treatment.

I think this is a very well-balanced summary of this research, and the take-home message is that almost no healthy person should be getting annual dental x-rays, as the risks likely outweigh the benefits. The American Dental Association’s official recommendations may call for repeat x-rays as frequent as 6 months in the rarer cases of people with severe cavities, but their 2006 review discusses how there’s very little evidence that healthy teeth benefit from routine annual x-rays.

Listen to Podcast
Click on the arrow below to listen to this podcast, or click here.

More Podcast Information

You can listen to all my previous podcasts at my podcast archive. You can always listen live to my radio interview each Wednesday around 7:35am Beijing time, on the Beijing Hour program on EZFM 91.5, which is broadcast from 7-8am every weekday by host Paul James. EZFM is the popular bilingual radio station on the China Radio International network, broadcasting here in Beijing and on multiple stations all over the world, as well as live online.


Follow me on:
Twitter @RichardStCyrMD
Facebook @BainbridgeBabaDoc

Leave a Reply