Panoramic X-rays
These X-rays show all the teeth and surrounding
structures on one large film. Theyare invaluable
for finding unerupted or impacted teeth, cysts,
jaw fractures, or tumours. Pictures are recorded
continuously on to film as the camera swings
around from one side ofthe jaw to the other.
There are three types ofX-ray. Each of
the different types is useful for
revealing particular dental problems.
Periapical X-rays
These X-rays give detailed pictures ofwhole
teeth and the surrounding gums and bone.
They show unerupted or impacted teeth, root
fractures, abscesses, cysts, tumours, and the
characteristic bone patterns of some skeletal
diseases. The film, in a protective casing, is
placed in the patient’s mouth and is held in
position behind the teeth to be X-rayed.
Bite-wing X-rays
These X-rays show the crowns ofthe teeth.
They are useful for detecting areas of decay
between teeth and changes in bone that are
caused by periodontal (gum) disease. The
film is in a holder with a central tab on to
which the patient bites.
dental emergencies include a
broken tooth (see
fracture, dental
) ;
, w hich may be due to an
abscess (see
abscess, dental
) ;
disease (see
gingivitis, acute ulcerative)
w hich causes ulceration, and bleeding
of the gums; and eruption of wisdom
teeth that cut into the tongue.
dental examination
An examination of the mouth, gums,
and teeth by a dentist as a routine
check or during the assessment of a
suspected problem.
Routine examinations are recommend-
ed so that tooth decay (see
caries, dental
) ,
gum disease (see
) ,
mouth can-
can be detected and treated at an early
stage, before they cause serious damage.
During the examination, the dentist uses a
metal instrument to probe for dental cavi-
ties, chipped teeth, or fillings. (See the
illustrated box on p.219.)
Dental X-rays
sometimes carried out to detect prob-
lems, for example with the jaw, that may
not be visible. The dentist also checks the
bite, that is how well the upper and the
lower teeth come together. Regular exam-
inations in children enable a dentist to
monitor the replacement of primary teeth
by permanent, or secondary, teeth. Refer-
ral for
treatment may be made.
dental extraction
extraction, dental
dental floss
A fine thread or tape, usually made of
nylon, that is used to remove plaque
plaque, dental
and food particles
from hard-to-reach areas between the
teeth and around the line of the gums
) .
Floss may be waxed or
unwaxed, and some types contain fluo-
ride. Flossing should be carried out
regularly, in addition to toothbrushing.
dental impaction
impaction, dental
dental X-ray
An image of the teeth and jaws that
provides information for the detection,
diagnosis, and treatment of conditions
that can threaten oral and general health.
The part to be imaged is placed between
a tube emitting
and a photograph-
ic film. Because X-rays are unable to pass
easily through hard tissue, a shadow of
the teeth and bone is seen on the film.
There are three types of dental X-ray;
periapical X-ray, bite-wing X-ray, and
panoramic X-ray.
Periapical X-rays are taken using X-ray
film held behind the teeth. They give
detailed images of whole teeth and the
tissues. They
unerupted or impacted teeth, root frac-
tures, abscesses, cysts, and tumours, and
can help diagnose some skeletal diseases.
Bite-wing X-rays show the crowns of
the teeth and can detect areas of decay
and changes in bone due to
Panoramic X-rays show all the
teeth and the surrounding structures on
one large film. They can show unerupt-
ed or impacted teeth, as well as cysts,
jaw fractures, or tumours.
The amount of radiation received
from dental X-rays is extremely small;
however, routine dental X-rays should
be avoided during pregnancy.
A paste, powder, or gel used with a
toothbrush to clean the teeth. Denti-
frice usually contains a m ild abrasive,
along with detergents, colourings and
binding and moistening
agents, and thickening agents. It also
usually has
added, and, some-
times, desensitizing agents.
dentigerous cyst
A fluid-filled
(lump or swelling)
surrounding the crown of an unerupted
tooth (see
eruption of teeth
) .
This type of
cyst may produce swelling or resorp-
tion (loss of substance) of the adjacent
tooth roots. Treatment is by extraction
of the affected tooth and by surgical
removal of the cyst.
The hard tissue that surrounds the pulp
of a tooth (see
) .
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