Eight-years results of site retention of anorganic bovine bone and anorganic bovine matrix.

Abstract The long term fate of some biomaterials is still unknown and the reports present in the literature are not conclusive whether these biomaterials are resorbed over time or not. Different reports can be found about the resorption behavior of anorganic bovine bone (ABB). The aim of the present study was a comparative histological and histomorphometrical evaluation, in the same patient, of two specimens retrieved from a sinus augmented with ABB and with anorganic bovine matrix added to a cell-binding peptide (PepGen P-15), respectively after a healing period of 6-months and after 8-years implant loading, to evaluate the resorption of both biomaterials. A unilateral sinus augmentation procedure with ABB (50%) and with PepGen P-15 (50%) was performed in a 54-year-old male patient. Two titanium dental implants with a sandblasted and acid-etched surface were inserted after 6-months. During this procedure, two tissue cores were retrieved from the sinus with a trephine, before implant insertion. After an additional 6-months, a fixed prosthetic restoration was fabricated. One of these implants, after a loading period of 8-years, fractured in the coronal portion and was removed. Both specimens, one retrieved after a 6-months healing period and the other after 8-years loading period, were treated to obtain thin ground sections. In the 6-months specimen, the histomorphometry showed that the percentage of newly formed bone was 27.2% ± 3.6%, marrow spaces 35.6% ± 2.3%, residual ABB particles 25.1% ± 1.2%, residual PepGen P-15 particles 12.1% ± 2.2%. In the 8-years specimen, the histomorphometry showed that the percentage of newly formed bone was 51.4% ± 4.8%, marrow spaces 40% ± 7.1%, residual ABB particles 6.2% ± 0.7%, residual PepGen P-15 particles 2.4% ± 0.5%. Both biomaterials underwent significant resorption over the course of this study.