Bone defect animal models for testing efficacy of bone substitute biomaterials.

Large bone defects are serious complications that are most commonly caused by extensive trauma, tumour, infection, or congenital musculoskeletal disorders. If nonunion occurs, implantation for repairing bone defects with biomaterials developed as a defect filler, which can promote bone regeneration, is essential. In order to evaluate biomaterials to be developed as bone substitutes for bone defect repair, it is essential to establish clinically relevant and testing models for investigating their biocompatibility, mechanical properties, degradation, and interactional with culture medium or host tissues.