Bma Illustrated Medical Dictionary

teethHard, 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

teethare lost. These teeth comprise

chisel-shaped, biting incisors; sharp,

pointed canines; grinding premolars;

and larger grinding molars.

teeth, care ofSee oral hygiene.

teethingThe 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.

telangiectasiaAn 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.)

temazepamA benzodiazepine drugthat

is used to treat insomniaand also as a

drug of abuse.

temperatureThe 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, shiveringcreates heat

by muscle activity, and constriction of

blood vessels in the skin minimizes

heat loss. When the body temperature

rises, sweatingresults in cooling, and

dilation of blood vessels in the skin

increases heat loss.

temperature methodSee contracep-

tion, natural methods of.

temporalA medical term meaning of or

near the temples or a temple.

temporal arteritisAn 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 biopsyof the temporal

artery. Treatment involves the use of a

corticosteroid drug. If this is not suc-

cessful, immunosuppressantsmay be

given. The disease usually clears up

within 2 years.

TEETH TEMPORAL ARTERITIS

T

TEETH

Crown Enamel

Dentine

Gum

(gingiva)

Pulp

Periodontal

ligament

Cementum

Jawbone

Nerve

STRUCTURE OF A TOOTH

Blood

vessel

Root