[Hyperparathyroidism]

The overproduction of parathyroid hormone as caused by a simple hyperplasia or an adenoma leads to pathological changes in various organs which are termed primary hyperparathyroidism. The blood phosphates increase in case of long-standing disturbances of the metabolism, e.g. chronic renal insufficiency. In this way and due to other causes, the production of parathyroid hormone is increased. The resultant clinical picture is termed secondary hyperparathyroidism. Both forms are associated with osseous changes also in the maxillofacial skeleton. Tertiary hyperparathyroidism may develop from secondary hyperparathyroidism if the metabolic disorder in the renal form cannot be eliminated by kidney transplantation and if the process in the parathyroid becomes independent (autonomous hyperparathyroidism). Besides these three forms, there are two others, quaternary hyperparathyroidism and quinary hyperparathyroidism, which are described.