Guided bone regeneration with autogenous block grafts applied to Le Fort I osteotomy for treatment of severely resorbed maxillae: a 4- to 6-year prospective study.

摘要

INTRODUCTION: Edentulism causes progressive bone resorption of the maxillae, which can lead to altered maxillo-mandibular relationships. The aim of the study was to evaluate the applicability of guided bone regeneration (GBR) to Le Fort I osteotomies with interpositional bone grafts for treatment of patients with severe maxillary atrophy. MATERIALS AND METHODS: Twenty consecutive patients characterized by severely atrophic maxillae were treated from January 2003 to January 2006 in order to resolve maxillary edentulism. All patients underwent pre-prosthetic surgery, including a Le Fort I osteotomy associated with autologous interpositional bone grafts to move the alveolar arch forward and to resolve the maxillary atrophy. Barrier membranes were also used to cover the bone grafts and the osteotomy line, favoring the healing process according to GBR principles. Maxilla advancement and alveolar crest augmentation were measured to assess the degree of reconstruction. A total of 154 implants were inserted in reconstructed maxillae 4 months after surgery and were restored with fixed full-arch dentures after another 4 months. Surgical and prosthetic complications were recorded and previously established implant success criteria were used to assess the success of this treatment protocol. RESULTS: The outcome of pre-prosthetic surgery and implant-supported rehabilitation was prospectively evaluated every year. All Le Fort I osteotomies were successfully carried out, with a mean maxilla advancement of 4.2 cm (range: 3.1-5 cm), which appeared to be stable during the follow-up. After a mean follow-up of 66.4 +/- 18.4 months, only four implants failed according to the success criteria, yielding a cumulative success rate of 95.8%. DISCUSSION AND CONCLUSIONS: Le Fort I osteotomies with the use of barrier membranes to cover the interpositional bone grafts can be a predictable treatment for edentulous patients with severely resorbed maxillae. The study data suggest that this approach makes it possible to compensate for both sagittal and vertical discrepancies due to maxilla atrophy, with a minimum resorption of advanced maxillae and grafted bone. A GBR-based protocol seems to lead to high implant success rates, although further randomized controlled studies are needed to demonstrate the usefulness and advantageousness of GBR.