Gingival Ulceration in Beagles Induced by Ra-226, Ra-228, or Th-228

¹ University of Utah College of Medicine, Salt Lake City, Utah

Relatively high retained burdens of Ra²²⁶ given by multiple injections, or Ra²²⁸ or Th²²⁸ administered via single injections to beagles, induced a severe type of gingival ulceration in part of the animals studied. This oral condition was characterized by marked sloughing of the gums, thus exposing the mandible and/or maxilla. It was invariably preceded by underlying bony changes and appeared to be secondary to this and related vascular impairment. The tendency toward healing was minimal. Lesser symptoms, without ulceration, were seen following single intravenous injections of relatively high doses of radium-226 or plutonium-239. Single injections, given intravenously, of 100 µc/kg of strontium-90 did not induce gingival ulceration.