Implant stability and new bone microarchitecture in atrophic maxillae reconstructed with allogenic grafts: A pilot trial

Abstract

ObjectiveRehabilitation of atrophic maxilla with allografts could be sometimes challenging in the choice. The present pilot clinical trial aimed to compare the change in stability over time of implants placed in particulate demineralized freeze-dried bone (DFDBA) or fresh-frozen bone (FFB) allografts in the posterior maxilla and to examine the microarchitecture of new bone formation. MethodsHealthy adult patients of both genders underwent bilateral maxillary sinus lifts. Only patients that presented with maxillary sinus pneumatization and who on tomographic examination were determined to have a residual bone height of less than 7 mm were eligible for inclusion. Each side was randomly grafted with DFDBA or FFB. Six to nine months after grafting, at the time of dental implant installation bone core biopsies, 10 mm in length, were obtained using a 2 mm short trephine drill. The bone biopsies were fixed in buffered formalin and randomly and blindly submitted to microcomputed tomography and histomorphological analysis. Implant stability was measured using resonance frequency equipment at three time points: immediately, 6, and 12 months after dental implant installment. ResultsA total of 10 patients were finally included. An increased bone volume was observed tomographically for all allografted regions. Implants placed in FFB show a significant enhanced stability after six months. Specially after one-year implant stability was significantly greater in FFB than in DFDBA grafts. Microtomographic analyses revealed that bone morphometric parameters were similar between allografts. ConclusionBoth allogenic grafts can be used to successfully rehabilitate the atrophic maxilla for implant placement.