Early radiographic changes in radiation bone injury.

A chronologic series of periapical radiographs was evaluated for the purpose of detecting damage to bone and tooth-supporting tissues in a patient receiving radiation therapy for a basal cell carcinoma of the mandibular gingiva. Widening of the periodontal space was one of the early radiographic changes observed. It is suggested, from the sequence of radiographic changes, that radiation-induced changed in the circulatory system of the bone might be primarily responsible for the resulting changes.