Objective To evaluate the biocompatibil ity of a new nano TCP/ gelatin / velvet antler polypeptide material. Methods The nano TCP/ gelatin / velvet antler polypeptide material was prepared, and the morphous was observed by scanning electron microscope. L929 and NIH/3T3 cell l ines were cultured conventionally. Acute toxicity test, hemolysis test, cell prol iferation and cytotoxicity test were used to evaluate the biocompatibil ity of the material. Results The compositemicrosphere material was about 10 μm in diamerter and had good spherical geometry, high monodispersity with nanometer size holes on the surface. Toxic symptoms such as hyperspasmia, palsy and death did not appear during the observing stage in acute toxicity test. Maximum hemolysis rate of the material was less than 5% which met the requirement of hemolysis test standard as a medical material. Different concentrations of the materials leaching l iquor could enhance the prol iferation of NIH/3T3 cells, which showed the good biologic activity. Toxicity grade was 0, and the material was no cytotoxic. Conclusion Nano TCP/ gelatin / velvet antler polypeptide material has good biocompatibil ity.
To investigate the cl inical results and the mechanism of bone heal ing for the repair of bone defects following tumor resection with novel interporous TCP bone graft, and to test the hypothesis of “structural transplantation”. Methods From January 2003 to December 2005, 61 cases of various bone defects following the curettage of the benign bone tumors were treated with interporous TCP, with 33 males and 28 females, including bone fibrous dysplasiain 8 cases, bone cyst in 23 cases, eosinophil ic granuloma in 12 cases, enchondroma in 13 cases, non-ossifying fibroma in 2 cases, and osteoblastoma in 3 cases. Tumor sizes varied from 1.5 cm × 1.0 cm to 7.0 cm × 5.0 cm. The plain X-ray, single photon emission computed tomography (SPECT) and histology examination were obtained at various time points after operation. The in vivo biodegradation rate of the implanted TCP was evaluated based on a semi-quantitive radiographic analyzing method. Histopathology examination was performed in 1 revision case. Results All the patients were followed up for 5 to 24 months after operation. They all had good wound heal ing and bone regeneration. There was neither significant reverse reaction to the transplanted material nor locally inflammatory reaction in all of the cases. The bone defects were repaired gradually from 1 to 6 months after operation (bone heal ing at average 2.6 months after surgery) with a bone heal ing rate up to 96.7%. There was only 1 recurrence case (eosinophil ic granuloma in ischium) 3 months after operation. Given revision operation, this case gained bone heal ing. Radiographically, the interface between the implanted bone and host bone became fuzzy 1 month after implantation, indicating the beginning of new bone formation. Three months later, the absorption of the interporous TCP was noticed from peripheral to the center of the implanted bone evidenced by the vague or fuzzy realm. New bone formation could be seen both in peri pheral and central areas. Six months later, implanted bone and host bone merged together and the bone defect was totally repaired, with 78.9% degradation rate of the implanted TCP. Twelve months later, the majority of the implanted bone was absorbed and bone remodel ing was establ ished. In the cases that were followed up for 24 months, the function of affectedextremity was excellent with good bone remodel ing without recurrence. In 2 cases, SPECT showed that nucl ide uptake could be observed in implanted site and the metabol ic activity was high both in the central as well as the peripheral areas of the graft 1 month after implantation, which was an evidence of osteogenesis. Pathologically, the interporous TCP closely contacted the host bone inside the humerus 1 month after grafting. The interface between the implanted bone and host bone became fuzzy, and vascularized tissue began growing inside the implanted graft as a “l ining” structure. Conclusion The interporous TCP proves to be effective for cl inical reparation of bone defects following tumor resection. The inside three-dimensional porous structure simulates the natural bionic bone structure which is suitable for recruitment related cells in-growth into the scaffold, colonizing and prol iferation companied with the process of vascularize, finally with the new bone formation. The novel interporous TCP may boast both bone conductive and bone inductive activities, as an appeal ing “structural transplantation” bone graft.
Objective To repair the defects in articular cartilage with collagen complex gradient TCP in vivo andto study the regenerated cartilage histomorphologically. Methods The models of defects in articular cartilage were madeartificially in both condylus lateral is femoris of mature rabbits, male or female, with the weight of 2.0-2.5 kg. The right defects were implanted with the material of Col/TCP as the experimental group and the left defects were untreated as the control group. The rabbits were killed at 4, 6, 8, 12 and 24 weeks after operation, respectively, with 6 ones at each time, and the macroscopic, histological, ultrastructural examinations and semi-quantity cartilage scoring employing Wakitanifa repaired cartilage value system were performed. Results Four weeks after operation, the defects in the experimental group were partly filled with hyal ine cartilage. Twelve weeks after operation, the defects in the experimental group were completely filled with mature hyal ine cartilage. Twenty-four weeks after operation, regenerated cartilage had no ataplasia. However, fibrous tissues were seen in the control group all the time. At 4, 6, 8, 12 and 24 weeks ostoperatively, the Wakitanifa cartilage scores were 7.60 ± 0.98, 5.69 ± 0.58, 4.46 ± 0.85, 4.35 ± 0.12 and 4.41 ± 0.58, respectively, in the experimental group and 10.25 ± 1.05, 9.04 ± 0.96, 8.96 ± 0.88, 8.88 ± 0.68 and 8.66 ± 0.54, respectively, in the control group. At 4, 6, 8, 12 and 24 weeks postoperatively, the collagen II contents were 0.28% ± 0.01%, 0.59% ± 0.03%, 0.68% ± 0.02%, 0.89% ± 0.02% and 0.90% ± 0.01%, respectively, in the experimental group, while 0.08% ± 0.02%, 0.09% ± 0.04%, 0.11% ± 0.03%, 0.25% ± 0.03% and 0.29% ± 0.01%, respectively, in the control group. Differences between the control group and the experimental group were significant (P lt; 0.05). By then, typical chondrocyte was observed by transmission electron microscope in the experimental group and much fiber with less fibrocyte was observed in the control group. Conclusion Three-dimensional scaffold collagen complex gradient TCP may induce cartilage regeneration to repair the defects of articular cartilage in vivo.