Biodegradable β-Tri-Calciumphosphate/Hydroxyethyl Methacrylate Enhanced Three Component Bone Adhesive Demonstrates Biocompatibility Without Evidence of Systemic Toxicity in a Rabbit Model

Bone gluing is an attractive surgical technique; however, its use in patients is hampered by a variety of side effects. Therefore, it was the aim of this ethically approved study to evaluate a novel biodegradable beta-Tri-Calciumphosphate (beta-TCP, Cerasorbo (R))-enhanced bone adhesive regarding its toxicity and biocompatibility in a rabbit model. Fifty healthy New Zealand White rabbits were assigned in the study (n = 21) and sham-operated control group (n = 29). In the study group, a cylindrical part (4.6 x 10.0 mm) of the proximal tibia and distal femur was removed, reimplanted, and bone adhesive was applied. Blinded physical examination and sampling for hematology, clinical chemistry, and acute phase proteins (haptoglobin, C-reactive protein (CRP)) was performed before surgery and after 12, 24, 48, 72, 240, and 504 h. Significant findings of the physical examination included a slightly higher grading of warmth (p = 0.0019) and pain (p < 0.0001) of the wound 240 h after surgery in the study group. No significant differences between albumin, haptoglobin, CRP, and urea concentrations in both groups were evident, whereas the study group demonstrated significantly lower leukocyte count, total protein, and globulin concentrations (p < 0.0001). As expected, both groups showed a marked transient increase in muscle enzymes (Creatine Kinase and Aspartate Aminotransferase) following the surgery (P < 0.0001). Twelve to 24 h after surgery, a significant decrease in ionized calcium from 1.38 +/- 0.12 mmol/L to 1.06 +/- 0.13 mmol/L, was noted in the study group (p < 0.0001). The results clearly indicated that the novel beta-TcP-enhanced bone adhesive showed good biocompatibility without significant evidence of acute or subacute local or systemic toxicity. (C) 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 90B: 767-777, 2009