Reconstruction of Extensive Bucco-Palatal Defects Using Twin Block Grafts: A Clinical Report of the Sandwich Technique in Two Cases

Introduction: Three-dimensional alveolar ridge defects in the anterior maxilla necessitate bone augmentation before implant placement. Bone volume, contour, and the overlying soft tissue form have to be optimized for an ideal outcome. A large three-dimensional defect needs osteogenic bone to predictably reconstruct the defect. Autogenous bone in the form of block and particulate is the graft of choice in such situations. Case Series: Two cases are presented here with severe three-dimensional alveolar ridge deficiency in the maxillary right lateral incisor and maxillary canine areas, respectively. Both cases had a three-dimensional bone and contour deficiency. Restorative-driven positioning of the implant necessitated augmentation of the buccal and palatal aspects of the defects. The defects were grafted with autogenous corticocancellous bone blocks harvested from the mandibular symphysis. In both sites, one block was placed on the buccal side and the other on the palatal side, "sandwiching" the host bone and the remainder of the gap filled with particulate autogenous bone. Implants were placed in both cases 5 months after the grafting, and the final restorations were placed 5 months subsequently. The implants and the grafts successfully integrated at the sites with stable bone and soft tissue levels. At the 3-year follow-up, both implants showed stable bone and soft tissue levels. Conclusion: Autogenous corticocancellous block grafts used in a sandwich technique reconstructed the lost bone volume, but also facilitated implant placement and optimal restorative outcomes.