The Dental Management of Patients with Endocrine Disease

Manifestations  : Hyper- or hypofunction.
Drug Therapy  : Diabetes: Oral hypoglycaemics, insulin. Corticosteroids.
Dangers  : Respiratory obstruction from thyroid goitre. Hypo- or hyperglycemia in diabetic patients. Insufficient corticosteroid ‘cover’.

Diabetic coma, a life-threatening dental emergency

The endocrine glands are responsible for the secretion of hormones. For instance, the thyroid gland secretes thyroxin, the pancreas secretes insulin and the adrenal gland secretes hydrocortisone. These substances circulate in the blood and control many of the bodily functions. Excessive hormonal secretion or hyperfunction may occur and can be treated in a variety of ways. Destructive disease leads to hormonal deficiency or hypofunction. The commercial availability of hormones permits the successful treatment of hypofunction. Consultation with the patient’s physician and control of endocrine disease are essential before elective surgery.

Disease of the thyroid gland in the neck is frequent. Enlargement of the gland or goitre does not adversely affect the course of surgery unless it is causing difficulty in breathing or swallowing or unless it is causing an uncontrolled hyperfunction called thyrotoxicosis or an uncontrolled hypofunction called myxoedema.

Diabetes is due to a relative or absolute deficiency of insulin. When mild, the disease is controlled well by careful dieting and weight reduction either alone or together with oral hypoglycaemic drugs. Severe disease necessitates the injection of insulin once or twice daily. Uncontrolled, severe diabetes leads to overbreathing, dehydration, shock and unconsciousness. This is a diabetic coma, a life-threatening emergency.

Hydrocortisone has been found to have a favourable influence on the course of many chronic diseases (e.g. asthma, arthritis, dermatitis and colitis) because hydrocortisone can suppress the immune response. There are many proprietary preparations of hydrocortisone and collectively they are 4 called corticosteroids. When so used the function of the adrenal gland is suppressed by a feedback mechanism during administration and for a variable period afterwards. During the period of suppression, the patient should receive a ‘steroid cover’ for any major stress or operation. This prevents the occurrence of adrenal failure, a condition leading to weakness, nausea and vomiting, progressive hypotension, drowsiness and, without treatment, death.

The insulin-dependent diabetic may become worse with the stress of major surgery, so continued control with injections of insulin is necessary. If fasting is required for the operation and the anaesthetic, insulin must be ‘covered with I.V. glucose to avoid dangerous hypoglycaemia. In these circumstances, the patient should be admitted to hospital. The oral antidiabetic drugs can cause hypoglycaemia if the patient fasts for longer than 4-6 hours.

Diabetics are usually able to recognise incipient hypoglycaemia by the onset of hunger, sweating, palpitations and tremor. The patient may appear drowsy and be sweating, and may lose concentration or become aggressive. The patient will look pale and the pulse rate will be high. The reaction can be relieved rapidly by taking 15-20 grams of sugar, i.e. a glass of fresh orange juice, or a cup of tea or coffee with 4 teaspoons of sugar (a teaspoon of sugar contains 5 grams). Persistent reduction of blood glucose leads to uncontrollable behaviour, unconsciousness and convulsions.  At this stage glucose must be given I.V. as soon as possible to avoid brain damage.