Treatment planning for sinus lift augmentations through use of 3-dimensional milled models derived from computed tomography scans: a report of 3 cases.

Objective: Three-dimensional models created by milling machines and stereolithography on the basis of 3-dimensional computed tomography scans have become essential in the diagnosis and therapy planning of oral and maxillofacial disorders. The purpose of this study, based on 3 clinical cases, was to examine the advantages of using 3-dimensional computed tomography scans and 3-dimensional milling models of the maxillary sinus before operative sinus elevation and of developing an operative layout with the aid of 3-dimensional models. REPORT DESIGN: Three patients with atrophy of the maxillary alveolar ridge received computed tomography scans before operative sinus elevation with iliac bone transplants and simultaneous dental implantation. These computed tomography data were used to create 3-dimensional graphic and plastic reconstructions of the maxillary sinuses.

Results: The 3-dimensional milling models enabled the development of an exact preoperative layout that took into consideration the exact shape of the iliac bone and the selection of dental screw implants. Furthermore, the models offered the possibility of producing an acrylic device for precise implant insertion. Precise planning resulted in good success with implantation 2 years after surgery.

Conclusion: Three-dimensional diagnosis and treatment layout have become an acknowledge method of operative maxillary sinus floor augmentation combined with simultaneous dental implantation in the upper jaw in difficult cases of sinus lift operations. As far as transplant shape and sinus anatomy are concerned, this has resulted in greater intraoperative precision. A 1-step procedure can thus be performed for augmentation and implantation through use of a well-adapted block transplant and dental screw implants in patients with extensive alveolar ridge atrophy.