Explains what dental X-rays are and why they are done. Covers commonly used types of dental X-rays, including bitewing and panoramic X-rays. Includes info on risks. Also covers what results mean.
X-rays are pictures of the teeth, bones, and soft
tissues around them to help find problems with the teeth, mouth, and jaw. X-ray
pictures can show cavities, hidden dental structures (such as wisdom teeth),
and bone loss that cannot be seen during a visual examination. Dental X-rays
may also be done as follow-up after dental treatments.
following types of dental X-rays are commonly used. The X-rays use small
amounts of radiation.
Bitewing X-rays show the upper and lower back
teeth and how the teeth touch each other in a single view. These X-rays are
used to check for decay between the teeth and to show how well the upper and
lower teeth line up. They also show bone loss when severe gum disease or a
dental infection is present.
Periapical X-rays show the entire
tooth, from the exposed crown to the end of the root and the bones that support
the tooth. These X-rays are used to find dental problems below the gum line or
in the jaw, such as
cysts, tumors, and bone changes linked to some
Occlusal X-rays show the roof or floor of the mouth and
are used to find extra teeth, teeth that have not yet broken through the gums,
jaw fractures, a cleft in the roof of the mouth (cleft palate), cysts,
abscesses, or growths. Occlusal X-rays may also be used to find a foreign
Panoramic X-rays show a broad view of the jaws, teeth,
sinuses, nasal area, and temporomandibular (jaw) joints. These X-rays do not
find cavities. These X-rays do show problems such as impacted teeth, bone
abnormalities, cysts, solid growths (tumors), infections, and
Digital X-rays can be sent to a computer to be recorded and
A full-mouth series of periapical X-rays (about 14 to 21
X-ray films) is most often done during a person's first visit to the dentist.
Bitewing X-rays are used during checkups to look for tooth decay. Panoramic
X-rays may be used occasionally. Dental X-rays are scheduled when you need them
based on your age, risk for disease, and signs of disease.
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.
solid growths (tumors), or abscesses.
Check for the location of
permanent teeth growing in the jaw in children who still have their primary (or
Plan treatment for large or extensive
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
who have no tooth decay and are not at high risk of getting cavities:1
Adults should have bitewing X-rays every 2
to 3 years.
Teens should have bitewing X-rays every 1½ to 3
Children should have bitewing X-rays every 1 to 2
For people who
have tooth decay or are at high risk of getting cavities: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. Dental X-rays are only done on your
mouth area, but if you are pregnant, routine dental X-rays may be postponed so
you do not have any radiation to your baby (fetus). If
dental X-rays are absolutely needed, a lead apron will be placed over your
belly to shield 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
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
thyroid gland from radiation.
else in the room wears a protective apron or stays behind a protective
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
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
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.
The amount of radiation used in dental X-rays is low. But there is always a slight risk of damage to cells or tissue from being exposed to any radiation, including the low levels of radiation used for this test. But the risk of damage from the X-rays is usually very low compared with the potential benefits of the test.
Pregnant women may not want to have routine dental X-rays taken until after
they give birth. Although there is no proof that a routine dental X-ray could
harm a developing baby (fetus), dentists usually suggest you wait to have your
X-rays until after the baby is born. Delaying the X-ray for a few months will
not result in further harm to teeth in most cases. There are times when the
severity of the dental problem requires an X-ray to deal with an urgent
X-rays are pictures of the teeth, bones, and soft
tissues around them to help find problems with the teeth, mouth, and jaw. Your
dentist can talk to you about your X-rays right after they are done.
No tooth decay is
No damage to the bones
supporting the teeth is seen.
No dental injuries, such as
tooth or jaw
fractures, are seen.
How this information was developed to help you make better health decisions.