Bionic Design And Manufacture Of Double Circulated System For Custom-made Synthetic Bone

It is very difficulty for bone to repair massive defects and the wide used methods are joint and material which have good intensity,but they have many complications.In the recent years,biological manufacture is developing,which study synthetic bone with rapid prototyping, cell culture and three- dimen-sional Rapid tooling. Synthetic bone can be replaced by new bone with metabolism, but the key is how to let the bioactive products(growth factor and osteocyte)and tissue fluid deep into the structure, which sustain the growth and regeneration.In this research, we design and manufacure a custom-made synthetic bone with double circulated system(microcosmic pipeline cycle and microcosmic hole cycle) and use dogs to discuss the feasibility of it.The synthetic bone has some advantages:1. There are two circulated system(microcosmic pipeline cycle and microcosmic hole cycle) which can let the bioactive products(growth factor and osteocyte)and tissue fluid deep into the structure respectively. 2. The dimension of synthetic bone is appropriate to develop new bone. The diameter of microcosmic pipeline is 250μm, microcosmic hole is 250μm, the connection among microcosmic holes is50-100μm. 3. Custom-made design. 4. Synthetic bone is connected with custom-made hemi-knee,which connected natural bone with intramedullary nail. This design can press-fit with the natural bone well and the artificial joint can press-fit with the cartilage well too and can avoid the osteoarthritis caused by cartilage necrosis and can preserve the tibial epiphysis by unilateral replacement.The study use the dog as the experimental subject to explore the process. A distal femur of a dog was scanned with Picker 6000 SCT with 1.0 slice thickness and pitch of 1.5, and the data obtained was treated in Voxel Q image workstation for 3D reconstruction with volume rendering technique. After having been downloaded to personal computer at 0.1mm interval, the transaxial 2D image data were converted into 2D digitized contour data by using image processing software developed by experimental team. The 3-D wire frame and solid images of femoral could be reconstructed when the digitized data were inputted into image processing software.Using the extracted contours, The custom-made bone is CAD in Surfacer, Then we design some shelves in the model, the CAD design is imported into the LPS-600A rapid prototyping machine, and the prototype is achieved. Furthermore, the prototype can be modified by hand according to the design. Afrer affuse TCP and calcine, we gained the artificial bone with double circulated system.Finally, the synthetic bone is implanted into the experimental dog and find out that the custom-made synthetic bone has a excellent result. Thesynthetic bone is press-fitted with the artificial joint and soft tissue.The study designed and manufactured the new custom-made synthetic bone with double circulated system (microcosmic pipeline cycle and...