This paper describes the effects of fibrin adhesive material (Beriplast P ®: BP) on bone induction in bone defects formed by surgical operation. Using adult Sprague-Dawley strain rats, bone defects were formed in the cortical bones of femurs with a dental round bar 1 mm in diameter, and immediately filled with BP. Bone defects without BP served as controls.
On days 1, 4, 7, 14, 30, 60, and 120 after operation, rats were fixed by transcardiac perfusion with an aldehyde mixture, and dissected bones were examined by light, transmission, and scanning-electron microscopy.
In the control bones without BP, the defective regions werefirst filled with blood clots (day 1) and then with granulated tissues containing numerous fibroblasts and macrophages (day 4). In BP-filled defects, the presence of BP and surrounding fibrous tissues significantly inhibited the formation of blood clots and granulated tissues, so bone formation from the surrounding cortical bone margins was induced faster than in control bones. In addition, granulated tissues were rapidly replaced by normal bone marrow in the BP-filled defects. Because BP is biological adhesive, at 4 days after operation, most of the BP was already absorbed, but no dead space was left in the defected regions. At 2 weeks after operation, the defects were completely filled with newly-formed bones, in which an active bone remodelling by osteoblasts and osteoclasts occurred.
These results show that BP is an effective biological tool in filling bone defects and in inducing new bone formation.