240 Theories and techniques of oral implantology

pallor (Fig. 6-50). The clinical signs in the mouth include paleness of the mucous membranes and lips. In more severe cases, petechial hemorrhage in the mouth lining, glossitis, and gingival bleeding may occur. The patient may also have a sore mouth.

Anemias resulting from sudden blood loss are characterized by a reduction in the number of healthy red blood cells. The remaining red cells are normal but simply inadequate in number. As soon as the number of such cells is increased to normal, either by replacement by the body or by transfusion in cases of severe loss, the symptoms desist. Patients with this type of anemia caused by bleeding hemorrhoids, peptic ulcer, or excessive menstrual bleeding may have dental implants inserted as soon as the condition is alleviated.

Those anemias caused by increased red blood cell destruction, a condition known as hemolytic anemia, are usually associated with systemic diseases. The remaining red cells tend to be fragile and rupture easily, and they are usually broken down more rapidly than normal by the spleen. Because the products of red cell destruction are converted by the liver into bile pigments that may appear in the surface tissues before excretion, the patient is often jaundiced. A patient suffering from this type of anemia is a poor risk for implants unless the cause of his anemia is corrected and the blood returns to normal.

When the red cells are abnormally formed or not produced in adequate numbers, the cause may be iron deficiency. Iron, which is needed for hemoglobin manufacture, may be deficient for two reasons: there is not enough in the diet, or it cannot be properly absorbed by the body and made available to the red cells. Iron deficiency anemias are easily controlled by administering, more of the deficient mineral in the diet or by administering it in a usable form, such as an intramuscular injection of an easily absorbable form of iron. As soon as the condition is controlled, the patient may be an acceptable candidate for an implant. In some cases in which the patient has developed poor eating habits because of tooth loss or problems in masticating with poorly fitting dentures, implant-borne fixed dentures may help treat the anemia.

When an anemia results from decreased bone marrow function or from the improper maturation of the red cells in the bone marrow because of a lack of maturing factors, then the condition is more serious. Cells in this type of anemia are often large and lack hemoglobin because they were released too early

from the bone marrow. The substance needed as a maturing factor by the bone marrow is vitaminB12, or a close relative of this vitamin. If insufficient amounts of B12 are in the diet or if normal gastric juice is not available to help absorb vitamin B12, the anemia results. Administering vitaminB12,_ or a concentrated liver extract either orally or by injection usually controls the condition. If, however, the vita-min is available to the bone marrow and the bone marrow itself cannot make use of it because of some other abnormality, the prognosis is poor.

Closely related to the above-mentioned condition is pernicious anemia, which usually occurs after the middle years. This condition is caused by the secretion of abnormal gastric juices that cannot convert vitamin B12, into usable form. As the disease progresses, the spinal cord is affected, with weakness, numbness, and eventual loss of limb control resulting. Life-long intramuscular injections of vitamin B12, liver extract, and folic acid are necessary; how-ever, the progressive degeneration of the spinal cord may not be stopped. Although to date nothing can be done to stop the progressive spinal cord degeneration, implants would not be harmful. As with other anemias that may require continual treatment, as soon as the immediate symptoms are controlled, implantation is possible and may indeed be beneficial in helping to ensure the patient a normal diet. While the patient may be unable to absorb the specific nutrient because of his systemic condition, he may at least enjoy nutritious food containing other essential vitamins and minerals.

Sickle cell anemia is a hereditary condition limited to the Negroid races. Sickling, or a distortion in the normal shape, of the red blood cells is believed to be an evolutionary development against malaria. Because of the distorted shape, the malarial parasites have difficulty in entering the red cells to mature there. The sickling trait, in itself, is not dangerous to the individual unless it is accompanied by some unknown factors that cause widespread destruction of the cells. When the bone is affected, implants cannot be inserted because of the fragile, porous structure of the bone (Fig. 6-51).

Erythroblastic anemia, an inherited abnormality usually limited to people of Mediterranean extraction, may occur in a mild form in adults. There are usually associated bone changes involving the long hones more than those of the skull and jaws. When the maxillae are affected they tend to be enlarged, with hyperplasia of the alveolar process resulting in a protrusion of the upper incisors. This plus an in-