Evaluating the implant candidate 245

cates that sufficient quantities of insulin may be produced but its effectiveness is decreased because of other factors.

Diabetes mellitus is characterized by a disturbance in carbohydrate, fat, and protein metabolism. It results in an increase in blood sugar, cholesterol, and acetone bodies and in the secretion of urine of a high specific gravity containing glucose and ace-tone bodies.

Diabetes appears to be hereditary, and more than one member of the family may have the condition. It can occur at any age. In young children the onset is usually acute. In adults it usually develops gradually, with about 50% of all cases occurring between the ages of 40 and 60. Obese adults are more prone to diabetes, and other precursors of the condition include infection and disorders of endocrine glands other than the pancreas. Adrenocortical steroids and other drugs may also trigger the disease in persons susceptible to the condition.

Diabetes is not curable, but the condition can be effectively controlled with modern therapeutic measures and the patient's cooperation. The patient must keep his weight down, get plenty of rest, exercise regularly, carefully control his diet, and be exceptionally attentive to cleanliness to prevent infections. Most patients, even the young, are able to administer insulin injections routinely.

In all patients who have had diabetes for a long time, changes frequently occur in the blood vessels and nervous system. The resulting complications include neuralgias, neuritis, cataracts, gangrene of the extremities, and arteriosclerosis. Of particular inter-

est to the implantologist is that a decrease in the blood supply in peripheral arteries retards the healing of local infections and injuries. While this may be one contraindication for implants, other factors, such as improved mastication and the elimination of irritating removable dentures, may be strong points in favor of implants for diabetic patients with well-controlled conditions.

Pregnancy. Although pregnancy certainly cannot be classified as an endocrine disorder, certain changes occur that temporarily contraindicate implants. During pregnancy, calcium is withdrawn from the teeth and bone and contributed to the embryo. Withdrawal from the bone takes place by a proteolytic action liberating the organic and inorganic salts from the calcified cementing substances. The salts are carried away by macrophages. The alveolar bone is particularly involved in this activity; this alone contraindicates implants.

Gingival involvement in pregnancy is another contraindication for implants (Fig. 6-54). The gingival involvement, although usually very mild (pregnancy gingivitis), is seen in about 50% of cases. It results either from local conditions or from a temporary endocrine imbalance. This gingival condition is not serious or difficult to eradicate, and it normally disappears a few months after childbirth. More serious gingival conditions, such as pregnancy tumors, exist in some women and may require surgical removal.

While alveolar disease, especially alveolar atrophy, is possible during pregnancy, it is actually rarely associated primarily with pregnancy, and then

Fig. 6-54. In pregnancy the gingiva may be red and swollen and bleed easily—a temporary contraindication for implants. (From Bhasker, S. N.: Synopsis of oral pathology, ed. 3, St. Louis, 1969, The C. V. Mosby Co.)