[The effect of irradiation using a linear accelerator on the dentognathic system of white rats].

The LMR-15c linear accelerator was used to irradiate the maxillofacial region of white rats. The results showed that when the irradiation dose reached 3,000 rad (TDF49), changes in pulpal tissue, periodontal tissue, parotid and submandibular gland, lymph nodes and oral mucosa began to take place and became severe as the times of irradiation and the cumulated doses increased. The body weight of rats had no obvious changes after irradiation, however, blood changes and during the recovery period showed that the injury of irradiation to immune function was obvious. The biological effects of X-rays, 60 Cobalt and linear accelerator were compared. The irradiation damage to the surface of oral tissues was milder in the latter, and no change could be found in jaw bones. It was suggested that the linear accelerator is the first choice to be selected for treatment of oral cancers.