ObjectivesBone defects were common conditions caused by trauma, sarcoma or infection. Small bone defects can be repaired automatically by bone induction、 conduction or regeneration. Large bone defects will not heal without bone transplantation.The current bone defects repairing materials include: Autogenous bone, allogenic bone, artificial materials, composite materiel etc. All of these materials were not ideal. It is clinical desirable to find ideal materials to repair larger bone defects. Bone tissue engi...