A recent episode of the "Dr. Oz Show" raised more questions than it answered regarding whether thyroid collars should be mandatory when having radiation-based procedures such as dental x-rays or mammograms.
The episode, which aired April 14, was intended to set the record straight after an email went viral in March based on advice the show's host, Mehmet Oz, MD, gave last year.
Dr. Oz invited experts from dentistry and radiology to comment on the email controversy and the pros and cons of thyroid shielding. But a combative Dr. Oz defended his original advice and ultimately turned the show into a lecture for healthcare professionals on the necessity of listening to their patients.
The backstory for the controversy stems from the rising incidence of thyroid cancer, which has increased fourfold since the 1970s. The 2010 episode of the "Dr. Oz Show" said that some of the increase could be due to radiation exposure from dental x-rays and mammograms, and advised the use of thyroid shields to reduce risk -- advice that prompted statements of opposition from imaging organizations.
Appearing on the April 14 show were luminaries from dentistry and radiology, including Ada Cooper, DDS, a consumer advisor for the ADA; Daniel Kopans, MD, director of breast imaging at Massachusetts General Hospital; Phil Evans, MD, director of the University of Texas Southwestern Center for Breast Care; and Jocelyn Rapelyea, MD, associate director of breast imaging at the Breast Imaging and Intervention Center of George Washington University.
The show exuded the atmosphere of a pep rally, with Dr. Oz noting that many doctors did not agree with his recommendation for women to wear a thyroid shield when having a mammogram. "I'm taking on my critics," he stated emphatically, and from that point on he barely let the panel of experts get an informative word in edgewise.
Much of the show focused on mammograms and whether they contribute to an individual's risk of thyroid cancer. The invited guests pointed out the impracticality of Dr. Oz's previous advice, indicating that the radiation dose exposure to the thyroid gland after 40 years of annual mammograms would be less than the background radiation received by sitting in a TV studio for 60 minutes.
Dr. Oz did interview an audience member who is a dental hygienist and who had seen the original show last year, which she said had prompted her to invest in thyroid shields for her patients.
"They are very inexpensive -- $25 -- so there's no excuse for not using these," she said.
"We are trying to get the word out, especially in the dental community," Dr. Oz responded, then directed some questions to Dr. Cooper regarding the use of thyroid shields in dentistry.
"If you get five dental x-rays in your lifetime, you have a fourfold increase in risk of developing thyroid cancer," he said to Dr. Cooper. "The ADA website says thyroid collars and aprons should be used whenever possible. Why does the ADA and the U.S. government recommend this?"
Dr. Kopans noted that dental x-rays are directed at the mandible and that the thyroid gland is just below the mandible -- seeming to imply that there is greater risk of radiation exposure to the thyroid gland from dental x-rays than mammograms.
But Dr. Cooper reiterated the ADA's position, noting that "the amount of exposure from dental x-rays is quite small compared to other sources, but collars and aprons can reduce radiation exposure to even lower levels."
