Dental X-Rays

Why It Is Done

Dental X-rays are done to:

• Find problems in the mouth such as tooth decay, damage to the bones supporting the teeth, and dental injuries (such as broken tooth roots). Dental X-rays are often done to find these problems early, before any symptoms are present.
• Find teeth that are not in the right place or do not break through the gum properly. Teeth that are too crowded to break through the gums are called impacted.
• Find cysts, solid growths (tumors), or abscesses.
• Check for the location of permanent teeth growing in the jaw in children who still have their primary (or baby) teeth.
• Plan treatment for large or extensive cavities, root canal surgery, placement of dental implants, and difficult tooth removals.
• Plan treatment of teeth that are not lined up straight (orthodontic treatment).

Without X-rays, dentists may miss the early stages of decay between teeth.

For people who have no tooth decay and are not at high risk of getting cavities:^{footnote 1}

• Adults should have bitewing X-rays every 2 to 3 years.
• Teens should have bitewing X-rays every 1½ to 3 years.
• Children should have bitewing X-rays every 1 to 2 years.

For people who have tooth decay or are at high risk of getting cavities:^{footnote 1}

• Adults should have bitewing X-rays every 6 months to 1½ years.
• Children and teens should have bitewing X-rays every 6 to 12 months.

How To Prepare

Before the X-ray test, tell your doctor if you are or might be pregnant. If you have an X-ray, he or she will have you wear a lead apron over your belly to protect your baby from the X-rays.

You do not need to do anything else before having a dental X-ray.

How It Is Done

Dental X-rays are taken in the dentist's office. The X-ray pictures are read by your dentist.

• A dental technician will cover you with a heavy lead apron as you sit upright in a chair. This apron shields your body from X-rays. The technician can cover your neck with the collar of the apron (called a thyroid shield) to shield the thyroid gland from radiation.
• Everyone else in the room wears a protective apron or stays behind a protective shield.
• The dental technician will have you bite down on a small piece of cardboard or plastic. The cardboard or plastic holds X-ray film. You may do this several times to get pictures of all your teeth. Some X-ray machines have a camera that circles your head and takes pictures of your teeth while you sit or stand.
• You may want to rinse your mouth before and after the X-rays.

Some dentists use digital radiography. This method uses an electronic sensor instead of X-ray film. An electronic image is taken and stored in a computer. This image can be viewed on a computer screen. Less radiation is needed to make an image with digital radiography than with standard dental X-rays.

How It Feels

X-rays take only a few minutes and are not painful.

Some people may gag on the plastic or cardboard that holds the X-ray film. People often find it easier to relax if they focus on something else (such as an object on the wall) and take slow, deep breaths through their nose during the X-rays.

What Affects the Test

Reasons you may not be able to have the test or why the results may not be helpful include:

• If you can't stay still or hold the X-ray plastic or cardboard in your teeth.
• If you have braces, retainers, dentures, bridges, and certain body piercings (ear, tongue, lip, cheek, or nose).

What To Think About

If you are going to a new dentist, have your other dentist send copies of your dental X-rays to your new dentist. You may not need any more X-rays with your new dentist.