ORAL MANIFESTATIONS OF IONIZING RADIATION

I. ORAL LESIONS AND EFFECT ON DEVELOPING TEETH OF SWINE EXPOSED TO 2000 K.V. TOTAL BODY X-RAY IRRADIATION

¹ Naval Medical Research Institute, National Naval Medical Center, Bethesda, Md.

Oral tissues, salivary glands, and developing teeth of 41 young swine were studied grossly and histologically to observe pathologic changes resulting from x-ray irradiation. These swine were selected from 120 animals which were exposed to 2000 K.V. total body x-ray irradiation in doses of about 250 to 800 roentgens in air. A hard-tissue sectioning machine was developed for making sections through undecalcified teeth and jaws. Gross changes in the oral mucosa consisted of petechial and ecchymotic hemorrhages in 49 per cent of the animals and marked ulceration in 9.8 per cent. Histologic study revealed irregular erosions of the mucosa in about 30 per cent of the animals and either petechial or massive hemorrhage around developing teeth of 70 per cent of the swine. Regional lymph nodes showed a high degree of sensitivity to x-ray irradiation by exhibiting hemorrhage and depletion of lymphoid cells. Salivary glands were among the less sensitive tissues, with regard to morphologic change; however, a definite decrease of basic staining granules was observed in acute stages of radiation sickness, with complete recovery in 30-day survivors. A characteristic kind of hypoplasia of the enamel of developing molarteeth was observed among swine which received more than 400 r. Ameloblasts actively producing enamel matrix appeared to be sensitive to irradiation. Other portions of the teeth showed minimal effects.