Purpose: To perform a preliminary validation with cone beam computed tomography (CBCT) of the combined use of intraoral bone blocks and biomaterials for total reconstruction of the atrophic maxilla. Materials and Methods: Consecutive cases of total edentulism of the maxilla (Cawood and Howell classes IV or V) treated with bilateral sinus floor elevation, mandibular bone block grafts, and biomaterials were evaluated prospectively. Implants were placed 14 to 16 weeks after grafting. Each patient received a CBCT scan preoperatively, immediately after bone augmentation, and at reentry. A three-dimensional reconstruction of the maxilla with volumetric calculations was obtained at each stage. Results: Fourteen patients participated. Successful graft integration occurred in all cases, with no major complications. Mean preoperative volume was 11,312 mm3. Mean postoperative volume was 19,997 mm3 immediately after surgery and 19,042 mm3 before implant insertion. The average percentage volumetric increase between the preoperative condition and the situation at reentry was 71.99%. One hundred eight implants were inserted. Immediate loading was possible with 81 implants in 10 patients. Conclusions: The rehabilitation of the severely resorbed maxilla remains a formidable challenge. The results of this study suggest that the use of mandibular bone blocks in combination with biomaterials is an effective, reliable procedure for the rehabilitation of the severely resorbed maxilla. Significant volume increases and adequate stability of the augmented areas at reentry were found with CBCT analysis. The grafted bone provided sufficient mechanical support to permit provisionalization and immediate loading. This technique enabled the restoration of function and esthetics with a fixed rehabilitation at 4 months. Schlagwörter: atrophic maxilla, bone grafting, bone substitutes, bone resorption, total reconstruction