How do dental X-rays work?
At first glance, X-rays can seem a little mysterious. How do they take images of the inside of a human body? What do dentists learn from studying them? Let’s remove the mystery and see why dental X-rays are a safe and important part of maintaining good oral health.
Dental X-rays, also referred to as radiographic images, are internal images of your teeth and jaws. Dentists use X-rays to examine structures they can’t see during a routine checkup, like your jawbone, nerves, and sinuses, and to check for issues like decay between the teeth, abscesses, and bone loss from gum disease.
How do dental X-rays work?
X-rays use radiation to capture images of the inside of your body. As the beam of electrons passes through you, it is absorbed differently by your teeth, bones, and soft tissues, and then captured as an image on a special film or digital sensor placed in the mouth.
The images appear in black, white, and shades of gray. Denser parts of your mouth like your teeth and bones appear whiter because they have blocked the radiation from reaching the film. Soft tissues, like your skin, organs, and muscles, will appear in shades of gray depending on how dense they are. The least dense structures and tooth decay can appear almost black.
Just like film photography, medical and dental radiology have been converting from traditional film to digital images. This offers a number of advantages — the X-ray images can be viewed and stored on computers, transferred to other providers, or enlarged or enhanced to detect changes that might not be evident on traditional film. Digital imaging also exposes the patient to much less radiation than conventional X-ray film.
What should I expect at my dental appointment?
Having X-rays taken is a quick, simple, and painless process. Your dental hygienist or dentist will guide you through the X-ray process, explaining each step along the way. They will place a lead bib over your neck, torso, and pelvic region to reduce your exposure to radiation and may step outside of the room briefly while the images are being taken.
You’ll need to hold still while the pictures are recorded — and that’s it! When the images are ready, your dentist will review them and check for:
Small areas of decay between teeth
Decay beneath existing fillings
Cysts and some types of tumors
Bone loss in the jaw due to periodontal disease
The position of unerupted or impacted teeth
A need for braces, implants, or dentures
If your dentist finds an issue, they’ll discuss treatment options with you.
How safe are dental X-rays?
Dental X-rays use very low levels of radiation and are generally safe. The amount of radiation you get from a full set of dental X-rays is comparable to the amount of radiation you absorb from everyday items like your TV and smartphone. The lead bib your dental hygienist places on you will further reduce your exposure.
However, all radiation can be damaging and is cumulative over a lifetime. Experts agree that X-rays should only be taken when they are absolutely necessary and if your dentist can’t make a diagnosis without the information only the X-ray can provide.
How long should you wait between dental X-rays?
This greatly depends on the age and oral health history of the patient, as well as the type of X-ray that is required. Remember, it’s always important to talk to your dentist to determine the right frequency depending on your oral health status.
Your dentist should perform an examination prior to the X-rays to determine if they are needed. If you are concerned about X-rays for you or your child, ask your dentist why they are necessary and what safety precautions are being taken.