Objectives: Tooth extractions lead to morphological changes of the alveolar ridge. For oral rehabilitation, a sufficient bone volume of the alveolar ridge is needed. In a clinical study was examined, whether the augmentation with Bio-Oss ^® collagen could preserve more bone volume than autologuos bone grafts.

Materials and methods: In this prospective clinical study, 17 patients with 20 extraction sites were evaluated. After tooth extraction, ten alveoles each were augmented with either autologous bone or Bio-Oss ^® collagen and covered with a resorbable membrane. The width of the alveolar ridge was measured immediately postoperative, and after four and six month, respectively. Prior to implant insertion after six months, a bone biopsy was taken from the augmented sites. The samples were evaluated histologically and histomorphometrically.

Results: The width of the alveolar ridge in the Bio-Oss ^® collagen group decreased about 9.33 ± 4.97% after four and 13.17 ± 5.08% after six months. The reduction in the group augmented with autologous bone was 11.73 ± 6.40% after four and 19.17 ± 8.38% after six months. Histological examination showed no signs of inflammation. After four months, the fraction of mature bone was 48.6 ± 24.4% in sockets augmented with autologous bone compared to Bio-Oss ^® collagen with 31.6 ± 20.2% ( p = 0.0317).

Conclusion: The present study suggested that autologous bone and Bio-Oss ^® collagen are suitable for socket preservation. However, both techniques could not entirely prevent tissue volume loss.