Dental X-Rays: What to Expect
Virtually everyone who visits the dentist will have X-rays taken at some point. Dental X-rays involve passing electromagnetic radiation through the jaw to produce images of the structures inside.
On an X-ray image, teeth, bones, fillings, and restorations appear lighter than the background, because they block more of the radiation than the surrounding soft tissue. Decayed areas or abscesses in the bone around teeth appear darker than healthy teeth, because the damaged teeth contain less radiation-blocking material.X-rays are valuable in uncovering problems in places that aren’t readily visible to the eye. X-ray images can reveal cavities inside and between the teeth, wisdom teeth that have failed to erupt, and bone deterioration below the gum line.
Exposure Risk Is Low
Because exposure to high levels of radiation can cause skin burns, cancer, and birth defects, some people fear getting dental X-rays. Today, though, the risk from X-rays is relatively low, thanks to improvements in technology and better regulation of the process. For example, modern dental X-ray machines narrowly focus radiation beams so that only your teeth are exposed. Better technology also can create the image more quickly, reducing your radiation exposure.
The newest breakthrough is a digital device that saves images in electronic files rather than on film. These high-resolution pictures require as little as 10 percent of the amount of radiation needed to create a traditional X-ray image.
Still, as a precaution, your dentist should cover your body with a lead apron when taking X-rays of your teeth. This prevents up to 94 percent of the radiation from reaching your chest, abdomen, and reproductive organs. For most X-rays, you can also wear a lead collar to shield your thyroid gland.
How Often They’re Needed
How often you need dental X-rays depends on the state of your dental health. Adults with no oral health problems are advised to have X-rays every two to three years. People who are at high risk for cavities or have a history of advanced gum disease may need X-rays more frequently. If you change dentists or see a specialist, bring your X-rays with you, so your new dentist won’t need to duplicate the existing films.
An Added Bonus
Wide-angle X-rays, called panoramic X-rays, may provide early warning of an impending stroke. Calcium deposits in the carotid arteries (the vessels that supply blood to the brain) show up on this kind of X-ray. These deposits sometimes break free of the artery walls and travel to the brain, where they can lodge in a smaller vessel, obstruct blood flow, and trigger a stroke. A November 2000 Journal of the American Dental Association article reported that data from this kind of X-ray were valuable in uncovering life-threatening blockages and spurring treatment.
Source: Dental Health for Adults: A Guide to Protecting Your Teeth and Gums. Copyright © by Harvard University. All rights reserved.