Edentulous patients with a severely resorbed maxilla frequently complain of ill fitting upper dentures. The continuing process of resorption, related to loss of teeth in the upper jaw, may evetually result in poor denture retention. Moreover, patient related factors, such as an extreme gagging reflex, may play a role as well. Improvement of prosthodontics may not be sufficient to compensate for the maxillary resorption, additional procedures, such as insertion of endosseous implants to support the prosthetic construction, are needed. However, reliable insertion of implants is often complicated in the upper jaw because of insufficient height and width of the alveolar process. In such cases, the insufficient bone volume of the maxilla has to be overcome by reconstructive pre-prosthetic surgery before implants can be installed at the preferred sites. To establish an adequate environment for the insertion of endosseous implants, various grafting procedures have been developed to increase the bone volume. Based on good clinical results, sinus floor elevation procedures are commonly used in reconstructive pre-prosthetic surgery. Sinus floor elevation surgery with autogenous bone grafts is a reliable procedure if properly planned and performed. The procedure is not without complications and surgeon must be able to manage problems that arise peroperatively as well as those that develop in the early and late postoperative phases. Bone grafting of the maxillary sinus floor, with bone augmentation for the insertion of implants, is reliable treatment modality with good long-term results.