Use of the sandwich osteotomy plus an interpositional allograft for vertical augmentation of the alveolar ridge

Introduction: Vertical augmentation of the alveolar ridge is necessary for extensive resorption of the alveolar ridge. Aim: To evaluate treatment outcome after alveolar ridge augmentation by a sandwich osteotomy combined with an interpositional allograft. Patients and Methods: The deficient alveolar ridges were augmented by a sandwich osteotomy combined with bovine collagen matrix as an interpositional allograft placed between the basal bone and the osteotomized fragment without fixation. Standardized lateral Cephalographs were taken of nine patients, before surgery, immediately postoperatively and 3 months after augmentation to evaluate the level of augmentation, bone loss and stability of the osteotomized fragment. Results: The augmentation ranged between 8.4 and 11.0 mm (mean 9.8 mm). Bone resorption in the crestal bone height ranged from 1.5 to 3.0 mm (mean 2.1 mm) after 3 months. Bone resorption in thickness of the osteotomized fragment ranged from 0.3 to 2.0 mm (mean 1.0 mm). Conclusion: Although there was some resorption of the superior and anterior parts of the reconstructed alveolar process, it was concluded that this procedure of augmentation is safe.