Autogenous bone ring for vertical bone augmentation procedure with simultaneous implant placement: A systematic review of histologic and histomorphometric outcomes in animal studies.

Statement Of Problem: The performance of the autogenous bone ring (ABR) technique used for the vertical bone augmentation procedure has not yet been determined.

Purpose: The purpose of this systematic review was to investigate whether the ABR technique for the vertical bone augmentation procedure with simultaneous implant placement enhances the histologic and histomorphometric outcomes in surgically created bone defects in animal models.

Material And Methods: An electronic search of 3 databases, Medline/PubMed, Science Direct, Lilacs, and a manual search of a reference list of relevant studies were performed. Only animal studies regarding vertical bone augmentation by using the ABR technique with simultaneous implant placement in surgically created bone defects were included in the review. The SYstematic Review Center for Laboratory Animal Experimentation tool was used to determine the risk of bias assessment, and the quality of included studies was assessed by using the Animal Research: Reporting in Vivo Experiments guidelines.

Results: Five studies were included in the qualitative analysis based on the inclusion and exclusion criteria. One study comparing the ABR technique with the bovine and biphasic ring reported a high percentage of bone area and bone implant contact of the ABR at 5 weeks of osseointegration. Similar histologic findings were reported in another study at 4 months of healing, but contrasting data were reported at 8 months. Another study reported an increase in the percentage of bone area and bone implant contact of the ABR technique from 3 months to 6 months of osseointegration. Two studies reported an increase in the percentage of bone area, and 1 study reported a decrease in the mean of bone implant contact, both with simultaneous and staged implant procedures.

Conclusion: Based on the limited available studies, the use of the ABR technique for the vertical bone augmentation procedure with simultaneous implant placement presented optimal histologic and histomorphometric outcomes in surgically created bone defects in animal models. However, the results of the current review are not sufficiently robust to support the use of the ABR technique for vertical bone augmentation in humans.