Six cases of old fracture of the tibia with large sear, bony defect, and shortening deformity of the limb were treated by elongation osteotomy at epiphysis and compression fixation of the fracture with external semilunar fixation frame. The bony defect ranged from 3cm to 6cm. Bony healing developed in all patients 4-7 months after operation. Early postoperative movement was suggested. The results revealed that there was an obvious improvement of the joint function and the shortened legs were corrected. The advantages of this method are that there is no need of bone grafting and operative treatment of the scar prior to treatment of the bone.
Objective To review research progress of corneal tissueengineering.Methods The recent articles on corneal tissue engineering focus on source and selection of corneal cells, the effects of growth factors on culture of corneal cells in vitro. The preparation and selection of three-dimensional biomaterial scaffolds and their b and weak points were discussed. Results The corneal tissue engineering cells come from normal human corneal cells. The embryo corneal cell was excellent. Several kinds of growth factors play important roles in culture, growth and proliferation of corneal cell, and incroporated into matrix.Growth factors including basic fibroblast growth factor, keratinocyte growth factor, transforming growth factor β1 and epidermal growth factor was favor to corneal cell. Collagen, chitosan and glycosaninoglycans were chosen as biomaterial scaffolds. Conclusion Human tissue engineering cornea can be reconstructed and transplanted. It has good tissue compatibility and can be used as human corneal equivalents.
Large defects of jaw caused by tumor, trauma and so on in oral and maxillofacial region lead to facial deformity, language and chewing dysfunction, which severely damage the patient’s life quality. Three-dimensional printing (3DP) is also named additive manufacturing (AM), which can print materials layer by layer to create three-dimensional objects. The complex shape of jaw defects can be accurately reconstructed using 3DP scaffold combined with image data, computer-aided-design and manufacture. It has specific advantages compared with traditional way of jaw reconstruction and has attracted much attention in the field of jaw tissue engineering recently. This article presented the progress of 3DP scaffold and its application in jaw reconstruction, providing a new idea for jaw reconstruction.
To summarize the medium-term cl inical result of bio-derived bone transplantation in orthopedics with tissue engineering technique. Methods From December 2000 to June 2001, 10 cases of various types of bone defect were treated with tissue engineered bone, which was constructed in vitro by allogenous osteoblasts from periosteum (1 × 106/ mL) with bio-derived bone scaffold following 3 to 7 days co-culture. Six men and 4 women were involved in this study, aged from 14 to 70 years with a median of 42 years. Among them, there were 2 cases of bone cyst, 1 case of non-union of old fracture, 6 cases of fresh comminuted fracture with bone defect, and 1 case of chronic suppurative ostemyel itis. The total weight of tissue engineered bone was 3-15 g in all the cases, averaged 7.3 g in each case. Results The wound in all the case healed by first intention. For 7 year follow up, bone union was completed within 3.0 to 4.5 months in 9 cases, but loosening occurred and the graft was taken out 1 year after operation in 1 case. The X-ray films showed that 9 cases achieved union except one who received resection of the head of humerus. No obvious abnormities were observed, and the function of affected l imbs met daily l ife and work. Conclusion Bio-derived tissue engineered bone has good osteogenesis. No obvious rejection and other compl ications are observed in the cl inical appl ication.
OBJECTIVE: To build the trestle of tissue engineering for skin with the collagen. METHODS: The collagen was obtained from the baby cattle hide pretreated by Na2S and elastinase and Protease M, then the collagen was dissolved in 0.5 mol/L acetic acid solution. The collagen was treated with Protease N to minimize its immunogenicity. The resulting collagen could be used to build the trestle of tissue engineering for skin because of good biocompatibility. The collagen molecular weight and structure were analyzed by SDS-PAGE. The bioactivity of trestle was tested in the experiment of the mice wound healing and the cell implantation. RESULTS: The SDS-PAGE result of the collagen treated by Protease M showed the typical spectrum of type I collagen. The built trestle was a collagen sponge matrix in which micropore size was 50-200 microns. It could accelerate wound healing and the implanted fibroblasts could proliferate well. CONCLUSION: The collagen treated by Protease N can get good biocompatibilily and is suitable for building the trestles of tissue engineering for skin with good bioactivity.
Objective To establish a scaffold model from heterogeneoussmall blood vessels. Methods Caudal arteries from 34 Wistar rats( average length 12.08±1.69 cm) were made into acellular blood vessel scaffolds. Some scaffoldswere observed by electron microscope, and others were transplanted to the cut ends of ear central arteries of male Japanese big ear white rabbits. Results Average external diameter was 0.74±0.08 mm in proximal, and 0.55±0.08 mm in distal end of rat caudal arteries. The small blood vessel scaffolds had shin wall whichwas white and soft, composed of fibrous tissues without cells. On the intima surface the fibrous tissues were arrayed densely in a grid-like pattern. After transplantation, the blood flow was reserved, and kept flowing freely in 24 hours. The pulsation of the transplanted artery was accessible and no blood leakage wasfound.Conclusion The natural scaffolds are composed of fibrous tissues, and can sustain the artery pulse pressure for 24 hours. It is better to suture the blood vessels by sleeve anastomosis.
目的:评价外固定支架治疗桡骨远端骨折的疗效。方法:2004年3月至2008年8月以外固定支架或辅以克氏针、可吸收螺钉内固定治疗桡骨远端骨折３7例。结果:31例获得4～28 个月(平均14 个月)的随访,所有骨折均临床愈合,平均愈合时间8周。腕关节功能按Sarmiento标准进行评定,优17例,良9例,可4例,差1例,优良率839%。结论:外固定支架治疗桡骨远端骨折疗效可靠,值得推广。
Objective To comment on the recent advances of production and application of the bio-derived scaffold in the tissue engineered peripheral nerve. Methods The recent articles were systematically analyzed, and then the production methods of the bio-derived scaffold and its application to the tissue engineered peripheral nerve were evaluated and prospected. Results B iological tissues were processed by some methods to produce the bio-derived materials. These mat erials could maintain the structure and components of the tissues. Moreover, the immunogenicity of these materials was reduced. Conclusion Application of the bio-derived materials is a trend in the fabricating scaffold of the tissue en gineered peripheral nerve.
Objective To review the recent progress of the researches in the field of cartilage tissue engineering, and to discuss the challenges in construction of tissue engineered cartilage. Methods Literature related with cartilage tissue engineering was reviewed and analyzed. Results Some techniques have been appl ied in cl inical. As far as the seeding cells, induced pluripotent stem cells have attracted much more attention. Current strategies of scaffold designing are trying to imitate both component and structure of natural extracellular matrix. Cartilage regeneration through the autologous cell homing technique el iminate the transplantation of exotic cells and has become the hot topic. Conclusion Successful treatment of the damaged cartilage using tissue engineering method will depend on the advances of stem cell technology development, biomimetic scaffolds fabrication and proper appl ication of growth factors.