One of the most frequent objections to my recommendations to include dental X-ray evaluation as part of a complete dental examination is patient concern about the amount of radiation to which they would be exposed. So, facts and basic science are necessary in order to make an informed decision about this sensitive subject.
We are all exposed to background radiation every day, 365 days a year. We cannot avoid it; it is there all the time. The only way to completely avoid it would be to wear totally lead-lined clothing covering our entire body. Not very practical. This background radiation comes from two main sources: cosmic radiation and radiation from ground sources. On average this background radiation is 2.5 to 3 mSieverts per year. What’s a Sievert? It is a unit of dose equivalent, or the biological effect of ionizing radiation. How does this compare to other sources of radiation? Suppose we lived in Colorado or New Mexico at an elevation above 5,000 feet. Then the background radiation would be increased by about .8 mSieverts. What would happen if we flew on a commercial flight at 35,000 feet for four to five hours? We would be exposed to another .035 mSieverts. You can see that there is radiation around us ALL the time.
How does this compare with the radiation exposure from dental X-rays? Well, it depends on the type of study that is performed. If it is just a 4 exposure limited bite wing series, then the radiation level is about .005 mSieverts if the office is using a digital system. An older film-based system would be about double that. That is close to the amount of background radiation we’re exposed to in just one day.
Here is a chart of common radiograph tests and their related exposure levels (Source: Federal EPA):
Chest X-ray .1
Head CT scan 2
Whole body CT scan 10
How does this compare with higher exposure limits?
The lowest annual dose at which any increase in cancer is clear is 100 mSieverts.
It is obvious that the radiation levels for dental X-ray examinations are very safe. You are more at risk from the radon in your basement than from the radiation from a dental X-ray examination.
If you would like more information or want to discuss this or any other dental matter, I would be glad to offer you a free 15-minute consultation. We use a digital radiographic X-ray system and all tests are done with lead apron coverage. Just call 610-838-6597 for an appointment.
Clarke Woodruff, DMD, has lived and worked in the Lehigh Valley most of his life. He left the region to complete dental school in Philadelphia and to serve four years as an officer/dentist in the U.S. Air Force. A member of Freedom High School’s first graduating class, Dr. Woodruff earned his undergraduate degree from Lehigh University. He received his Doctor of Dental Medicine degree (DMD) from the University of Pennsylvania in 1976 and opened his Hellertown dental practice at 800 Main St., Suite 102, in 1980. He was named a Fellow of the Academy of General Dentistry in 1987, after successfully completing a comprehensive examination and more than 500 hours of continuing education. Dr. Woodruff maintains active membership in the American Dental Association, Pennsylvania Dental Association, Lehigh Valley Dental Society and American Academy of Cosmetic Dentistry. In addition to his private practice, Dr. Woodruff is devoted to the education of tomorrow’s dentists as current chair of the Department of Dental Medicine at Lehigh Valley Health Network. His outside interests include vintage race cars, woodworking and singing. Find him on Facebook and check out his website. For more information or to schedule an appointment, please call 610-838-6597 or contact him via email.