Implant supported restorations were placed in 137 atrophic ridges that were augmented with cancellous block-bone allografts. Recipient site complications associated with block grafting were recorded.
Total block-graft failure occurred in 7% of cases and partial block graft failure occurred in 8% of cases. The implant failure rate was 4.4%. Soft tissue complications included membrane exposure (42 of 137), incision line opening (41 of 137), and perforation of the mucosa of the grafted bone (19 of 137). A higher rate of complications was noted in the mandible.
Soft tissue complications did not necessarily result in total loss of cancellous block allograft. Total bone-block failure (8% of cases) and implant failure (4.4% of cases) were uncommon with block grafting although approximately 30% of patients experienced adverse events.
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J Periodontol. 2010 Dec;81(12):1759-64
Analysis of complications following augmentation with cancellous block allografts.
Chaushu G1, Mardinger O, Peleg M, Ghelfan O, Nissan J.