Maxillary sinus augmentation with the xenograft Bio-Oss and autogenous intraoral bone for qualitative improvement of the implant site: A histologic and histomorphometric clinical study in humans

The aim of the present clinical study was to determine, through histologic and histomorphometric investigations of human bone specimens, whether the a ddition of autogenous bone to the bone substitute material Bio-Oss can prod uce a high-quality implant site. To improve vertical bone height, 13 sinus floor elevations were carried out in a total of 12 patients. Augmentation o f the maxillary sinus floor was completed using a mixture of Bio-Oss and bo ne harvested intraorally from the mandibular symphysis, the retromolar spac e, or the tuberosity region. Following an average of 7.1 months of healing, 36 Branemark System implants were placed. During this surgical interventio n, 23 cylinder-shaped bone biopsies were taken from the augmented maxillary region using trephine burs. Histologic analysis of the bone biopsies revea led that the Bio-Oss granulate was well-integrated into the newly formed bo ne; 33.1% (+/-: 12.4%) of the substitute material surface was in direct con tact with bone. Histomorphometric analysis of the samples revealed an avera ge percentage proportion of bone of 18.9% (+/- 6.4%). The bovine substitute material and soft tissue occupied, respectively, 29.6% (+/- 8.90/4) and 51 .5% (+/- 9.4%) of the measured surface. When the implants were uncovered af ter an average healing phase of 6 months, all 36 implants had become osseoi ntegrated. The combination of osteoconductive Bio-Oss and osteoinductive au togenous bone thus proved to be a material suitable for application in sinu s floor augmentation.