GBR Versus Allogenic Bone Block

Objective: The objective of this study is to compare the histological, clinical, and radiographic outcomes of particulate bone substitutes versus allogenic bone block grafts for primary bone augmentation in the posterior mandible. Materials and Methods: This randomised controlled clinical trial included adult patients in need for a staged bone augmentation prior to implant placement in the posterior mandible. Patients were randomly assigned to one of two treatments groups. Patients allocated in the BBL group received allogenic bone blocks, whereas patients in the GBR group received allogenic bone granules for the primary bone augmentation. In both groups grafting materials were covered with a resorbable collagen membrane, which was fixated with non-resorbable fixation pins. The primary outcome of this study was defined as the composition of the histological samples at least 6 months after the primary bone augmentation. Secondary outcomes included graft survival rates, the need for further augementation procedures at time of implant placement, soft tissue measurements and radiographically and clinically analyzed changes in bone width and radiographically analyzed changes in bone volume. These outcomes were measured at baseline (prior to bone augmentation surgery) and at the follow-up (at least 6 months after bone augmentation).