Changes of the thyroid gland and periodontal tissues of marmosets related to experimental hypothyroidism.

Adult marmosets of both sexes, weighing about 300 grams received intraperitoneal injections of 1.5 mCi of I131. Alterations in periodontal and thyroid gland tissues were determined 30, 45, 60 and 90 days after the administration, using the histological method. In the thyroid gland, degeneration and necrosis of the follicles and absence of the colloid substance with later substitution of the glandular tissue by a cicatricial fibrous tissue were observed. In the periodontium changes occurred in the alveolar bone, followed by degeneration of the periodontal ligament with areas of hyalinization from 30 days period up to the conclusion of the experiment. The cementum and the dentine were the last structures to present evidences of degeneration, showing areas of resorption only in the 60 and 90 days periods.