TEETH
TEMPORAL ARTERITIS
TEETH
Crown______
STRUCTURE OF A TOOTH
Enamel
Dentine
Gum
(gingiva)
Pulp
Periodontal
ligament
Cementum
Jawbone
Nerve
Blood
vessel
T
teeth Hard, bone-like projections set in
the jaws and surrounded by the gums.
The teeth are used for
mastication,
help
to form speech, and give shape to the
face. At the centre of each tooth is the
pulp, which contains blood vessels and
nerves and is surrounded by hard den-
tine. The part of the tooth above the
gum, the crown, is covered by enamel,
the hardest substance in the body.
The roots of the tooth, which fit into the
jawbone,
are
covered
by
bone-like
cementum. Humans have 32
permanent
teeth
, which erupt after the
primary
teeth
are lost. These teeth comprise
chisel-shaped, biting incisors; sharp,
pointed canines; grinding premolars;
and larger grinding molars.
teeth, care of See
oral hygiene.
teething The period when a baby cuts
his or her
primary teeth
(see
eruption of
teeth
). While teething, a baby may be
irritable, fretful, clingy, have difficulty
sleeping, and may cry more than usual.
Symptoms may be relieved by the use
of painkilling gels that are rubbed on
the gums, or liquid preparations.
telangiectasia An increase in the size
of small blood vessels beneath the sur-
face of an area of skin, causing redness
and a “broken veins” appearance. It is
most common on the nose and cheeks.
There may be no obvious cause, or the
condition may be due to many years of
excessive alcohol consumption,
rosacea
,
overexposure to sunlight, or a connective
tissue disease such as
dermatomyositis.
Telangiectasia is not a cause for con-
cern, but the veins can be removed in
some cases by electrodesiccation (elec-
trical destruction of the upper layers of
the skin). (See also
spider naevus
.)
temazepam A
benzodiazepine drug
that
is used to treat
insomnia
and also as a
drug of abuse.
temperature The degree of hotness of a
body or substance. In the human body,
the temperature must be maintained at
around 37°C for optimum functioning.
Body temperature is maintained by the
hypothalamus
, which monitors blood
temperature and activates mechanisms
to compensate for changes. When body
temperature falls,
shivering
creates heat
by muscle activity, and constriction of
blood vessels in the skin minimizes
heat loss. When the body temperature
rises,
sweating
results in cooling, and
dilation of blood vessels in the skin
increases heat loss.
temperature method See
contracep-
tion, natural methods of
.
temporal A medical term meaning of or
near the temples or a temple.
temporal arteritis An uncommon dis-
ease of older people in which the walls of
the arteries in the scalp over the temples
become inflamed. Other arteries in the
body may also be affected. The cause is
unknown, but the condition is often
associated with
polymyalgia rheumatica.
Symptoms may include severe headache
on
1
or both sides, scalp tenderness, a
low fever, and poor appetite. In about
half of the cases, the arteries supplying
the eyes are affected, which may cause
sudden blindness if left untreated.
Diagnosis of temporal arteritis is made
by
blood tests
(including
ESR
) and, in
some cases, by a
biopsy
of the temporal
artery. Treatment involves the use of a
corticosteroid drug
. If this is not suc-
cessful,
immunosuppressants
may be
given. The disease usually clears up
within
2
years.
540
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