Dental roentgenologic manifestations of systemic disease. I. Endocrine disturbances.

Abstract

The endocrine glands which are known to have an influence upon the skeleton are the pituitary, thyroid, parathyroid) adrenal, and sex glands. Any quantitative change in the hormones secreted by these glands, be it underproduction or overproduction, may lead to disturbances of growth and metabolism of bones. The teeth and jaws reflect endocrine dysfunction just as do other parts of the skeleton, and the dental effects may remain as a permanent record of the disorder. Any influence that endocrine dysfunction may have upon the teeth themselves is almost entirely limited to the period of their development and is manifested by either retardation or acceleration of development and eruption, or by faulty and imperfect structural development. Defects which occurred in the incisor teeth of rats deprived of their parathyroid glands first led Erdheim (1), in 1911, to the realization that secretion from these glands has an influence upon calcium metabolism. In general, the size of the teeth is not altered in endocrine disturbances. Dwarfs do not have dwarfed teeth, nor are the teeth of the giant necessarily larger than those which might well be seen in persons of normal size. Teeth in which calcification has been completed prior to the onset of the disturbance are unaffected. Hard tooth structure undergoes no demineralization or hypercalcification; therefore) there is no change in radiographic density. Thus the teeth can serve as a gauge of density or as a penetrometer to aid in the recognition of cases in which skeletal complications are present. Effects of endocrine disturbances upon the bone of the jaws are in a large measure similar to those on other bones of the skeleton. Disturbances which occur during the period of growth and development may be manifested by retardation and underdevelopment or by acceleration and overdevelopment of the jaws. In instances in which overdevelopment of the skeleton occurs, the mandible, because of the normal persistence of growth cartilage of the condyle, is prone to undergo relatively greater enlargement than the majority of the other bones. Where the structure or quality of the bone is altered, the intraoral dental roentgenogram is of value, for it often reveals minimal distortion of trabecular pattern and mild demineralization in instances in which it may not be demonstrable in other roentgenograms. One of the changes which may take place in case of demineralization is the obliteration or disappearance of the lamina dura, the uniform radiopaque line which represents the alveolar socket. This observation has been made use of in the diagnosis, notably, of hyperparathyroidism. It is not, however, peculiar to hyperparathyroidism, but is seen also in several other conditions in which there are associated demineralization and osteoporosis, among them, Cushing's syndrome, sprue, vitamin D deficiency, and Paget's disease.