The surgical treatment of malignant tumors will consist of resection of part of the maxilla. Sometimes even surrounding tissues may be removed. The extent of the resection depends on the localization and size of the tumor.The defects may be grouped as follows :1. Palatal defects (in the hard or in the hard and the soft palate)2. Defects in the alveolar ridge.3. Defects in the buccal surface of the maxilla (in the event of tumors in the maxillary sinus).4. Actual maxillary defects (marginal resections, retaining the (unilateral or bilateral) nasal structures (subtotal resections, retaining the orbital floor) (total resection with removal of the orbital floor, too).