Encrustations of the trachea as a complication of radical surgery of the head and neck have proved to be a serious and demanding problem in some instances. These encrustations are associated with the postoperative changes occurring in patients who have been subjected to tracheostomy. They impose an embarrassment to his respiration and indeed may precipitate asphyxiation and death. Care and prevention require diligent and aggressive supervision. INCIDENCE The incidence of encrustations of the trachea is not great. Approximately 10% of all patients who underwent resections requiring a temporary or permanent tracheostomy have postoperative encrustations to some degree. In only 2% did encrustations develop that were occlusive in size and capable of precipitating a dramatic airway block (fig. 1). If one is not alert to this problem and has not instituted prophylactic measures, the incidence may be higher. The vast majority of these cases occurred during the winter months. There was