The authors present their initial experience with the preparation Wobenzym as a radioprotective agent. Systemic enzyme therapy was administered to 10 patients with squamous- cell carcinoma of the oropharynx after buccopharyngotomy with mandibulotomy and osteosynthe- sis with subsequent postoperative radiotherapy. Before the beginning of the prospective investigation Wobenzym was administered to three patients after buccopharyngotomy and mandi- bulotomy with osteosynthesis and postirradiation osteoradionecrosis, together with Dalacin. In patients with postirradiation necrosis also laboratory examinations of urine were made to detect pyridinium cross bonds as a marker of impaired bone metabolism. Postirradiation mucosal and osseous changes were evaluated according to the WHO scale. In none of the patients radiotherapy had to be discontinued on account of severe mucositis or dermatitis. In none of the patients of the group late postirradiation changes were detected such as osteoradionec- rosis. Administration of systemic enzyme therapy as a radioprotective procedure is evaluated favourably by the authors.

        Key words: mandibulotomy, osteoradionecrosis, radioprotective agent, pyridinium cross bonds.