Histological evaluation of Bio-Oss in a 2-stage sinus floor elevation and implantation procedure. A human case report

Deproteinized cancellous bovine bone (Bio-Oss) was placed as a grafting material for sinus floor elevation in the right posterior maxilla. After 6 months of healing, 3 cylindrical titanium-plasma coated implants were inserted. Six months later at the abutment connection, it was realized that 1 of the implants could not be reconstructed due to unfavorable positioning. This implant was removed along with a small portion of the surrounding peri-implant tissues. The specimen was processed according to standard techniques for hard tissue histology. In both the grafted area and the previously existing area of the sinus floor the bone was primarily of lamellar structure. Intimate contact between newly formed bone and the particles of the graft was present. No overt signs of resorption of the graft particles were visible. Histomorphometric analysis revealed 63% of implant-bone contact in the zone of pre-existing bone, and 73% in the grafted zone. The area density of bone amounted to 27% in the non-grafted as compared to 28% in the grafted area. In conclusion, this case report documented that deproteinized bovine bone, when used as a grafting material for augmentation of the sinus floor, may lead to proper osseointegration of a dental implant.