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1.
Twenty-one porous hydroxyapatite-tricalcium phosphate ceramic cylinders 1.5 cm long and 1.2 cm in diameter were swathed with fresh autogenetic periostea taken from 21 dogs and implanted in the same animals' muscles to get living ceramic bone substitutes. These substitutes contained autogenetic growth stimulators including osteoblasts and other multipotential cells. One month later, they were transferred to the segmental bone defect sites created in femoral diaphysis of the same animals. The roentgenograms showed that in time the boundaries between the cylinders and bone sections became vague. X-ray diffraction analysis indicated that the spectra of the samples tended to be similar to those of natural bones by 6 months postoperatively. Their bending strengths also increased gradually. After the cylinders were transferred from muscles to the bone defect sites, newly formed bone tissues rapidly increased and the cylinders gradually fused with the contacted bones 2 months later. By 4 and 6 months, bone tissue occupied most areas of the materials. The ratio of newly formed bone tissue had a large lead over the materials. Haversian systems were clearly observed and matured bone tissues filled the ceramic pores and connected with each other. Results suggested that culturing complexes that consist of autogenetic periostea and biomaterials, taking advantage of living organic culturing medium, should be an effective approach to get satisfactory bioactive bone substitutes. It also provides a basis for clinically repairing bone defects in bearing sites with complex bioceramics.  相似文献   

2.
Twenty-one dogs were used to study the osteoinductivity and biomechanical properties of a biphasic porous ceramic with autogenic periosteum implanted in muscle. The ceramic implants were swathed in fresh periosteum derived from the same animals and implanted in the femur muscles. The other two groups of animals served as controls using the same material implanted in the femur bones and muscles without periosteum. Biomechanical measurements showed that, in the muscles, the experimental group had a higher bending strength than the unswathed group by the time the samples were harvested. Six months postoperatively, the strength of the samples in the experimental group had almost reached that of normal bones. The results of X-ray diffraction and infrared spectrometric analysis suggested that the degradation rate and speed of tricalcium phosphate (TCP) of the ceramic in the experimental group were faster than in the unswathed samples, but slower than in samples implanted in bones. The bone replacement and bone-inducing activity were excellent in the periosteum-swathed samples. Histologically, satisfactory bone repair was seen in the experimental samples. All results indicate that autogenic periosteum could increase bioactivity of ceramics in heterosites and improve bone formation in the surroundings of porous calcium phosphate ceramics. The data also infer that the complicated procedure of culturing bone growth factors with biomaterials in vitro to obtain bioactive grafts could be replaced by this relatively simple method.  相似文献   

3.
背景:随着组织工程技术的发展,多孔生物陶瓷被越来越多的运用到骨缺损的修复中,当前的研究主要集中在这种生物陶瓷的合成及其各项性能的评价。 目的:研究一种新型骨水泥的制备方法并测定其理化性能及与成骨细胞的生物相容性。 方法:共沉淀法制备双相钙磷生物陶瓷粉体,利用胶体团聚成颗粒,烧结后得到颗粒状、多孔羟基磷灰石/磷酸三钙生物陶瓷,并按不同比例与高纯度医用半水硫酸钙混合制备钙磷陶瓷/硫酸钙骨水泥。 结果与结论:X射线衍射证实合成物质为双相钙磷陶瓷,颗粒状双相钙磷陶瓷具有多孔网状结构,骨水泥在   3 min内保持可塑状态,固化时间为15 min,固化温度为36.5 ℃,压缩强度最高为5.82 MPa,MTT毒性级为0级,成骨细胞在材料表面生长良好。中国组织工程研究杂志出版内容重点:生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接:  相似文献   

4.
Yuan J  Cui L  Zhang WJ  Liu W  Cao Y 《Biomaterials》2007,28(6):1005-1013
Tissue engineering has become a new approach for repairing bone defects. Previous studies have been limited to the use of slow-degradable scaffolds with bone marrow stromal cells (BMSCs) in mandibular reconstruction. In this study, a 30 mm long mandibular segmental defect was repaired by engineered bone graft using osteogenically induced autologous BMSCs seeded on porous beta-tricalcium phosphate (beta-TCP, n=5). The repair of defects was compared with those treated with beta-TCP alone (n=6) or with autologous mandibular segment (n=4). In the BMSCs/beta-TCP group, new bone formation was observed from 4 weeks post-operation, and bony-union was achieved after 32 weeks, which was detected by radiographic and histological examination. In contrast, minimal bone formation with almost fibrous connection was observed in the group treated with beta-TCP alone. More importantly, the engineered bone with BMSCs/beta-TCP achieved a satisfactory biomechanical property in terms of bending load strength, bending displacement, bending stress and Young's modulus at 32 weeks post-operation, which was very close to those of contralateral edentulous mandible and autograft bone (p>0.05). Based on these results, we conclude that engineered bone from osteogenically induced BMSCs and biodegradable beta-TCP can well repair the critical-sized segmental mandibular defects in canines.  相似文献   

5.
聚DL-乳酸/羟基磷灰石复合材料修复长骨缺损的实验研究   总被引:3,自引:0,他引:3  
目的 :评价羟基磷灰石 (HA)复合聚DL 乳酸 (PDLLA )制备的材料体内成骨能力。方法 :将PDLLA和PDLLA/HA( 2 0wt % )材料采用盐结晶颗粒沥滤法制成三维多孔材料 ,45例 1cm兔桡骨去骨膜缺损分为三组 ,分别植入 2种材料和作空白对照 ,术后 2 ,4,8,12周行X线、组织学及扫描电镜观察骨生成状况 ,8、12周行生物力学测试 (三点折弯强度 )。结果 :泡沫状PDLLA/HA ( 2 0wt % )材料比纯PDLLA成骨更好 (P <0 .0 5 ) ,实验组与对照组相比差异有显著性 (P <0 .0 5 )。结论 :PDLLA具有良好的生物相容性 ,制成多孔状具有较好的骨传导性能 ,HA( 2 0wt % )的加入促进了多孔PDLLA的骨传导能力 ,提高了骨生成的质量。PDLLA/HA( 2 0wt % )复合材料是一种有临床应用前景的骨移植材料。  相似文献   

6.
为研制理想的、能较快修复长骨大段骨缺损的陶瓷人工骨 ,我们将管状磷酸三钙 ( TTCP)和柱状磷酸三钙 ( CTCP)陶瓷人工骨分别植入兔桡骨于 1cm缺损处。术后 4、12周时取材 ,作大体组织形态学、新骨形成定量观察及抗折强度测试。术后 4、12周时 TTCP内新骨形成量明显多于 CTCP,术后 12周时 ,植入材料与宿主骨结合紧密 ,TTCP的降解速度快于 CTCP,抗折强度前者明显高于后者 ( P<0 .0 1)。研究结果表明 ,TTCP比 CTCP设计更合理 ,能更快促进长骨大段骨缺损的修复 ,是一种较理想的人工骨材料  相似文献   

7.
Porous interconnected hydroxyapatite (HA) and HA/tricalcium phosphate (TCP) (60/40) ceramics are promising materials for hard tissue repair. However, the mechanical properties of these materials have not been accurately determined under weight-bearing conditions. In this study, newly developed HA and HA/TCP (60/40) ceramics were used with intramedullary fixation in segmental bone defects of rabbits. Early radiological, histological, densitometric and biomechanical changes were evaluated. The mean radiological grade of healing and bonding to bone was higher in HA/TCP (60/40) ceramics than that of pure HA ceramics but the difference was not statistically significant. The densities of both implanted ceramics improved with time, supported by the histological evaluation of bone matrix ingrowth into ceramic pores, whereas the densities at the bone–ceramic interface decreased gradually. Flexural resonant frequencies and three-point bending strength increased, revealing an increase in mechanical stability during this early critical time interval where implant and/or bone–implant interface failures occur frequently. It can be concluded that both HA and HA/TCP (60/40) ceramics have a limited application in the treatment of load-bearing segmental bone defects but did not fail at the early stages of implantation.  相似文献   

8.
Long intercalated defects in canine ribs can be repaired successfully using porous beta-tricalcium phosphate (beta-TCP) cylinders, infused with a biodegradable polymer (poly D,L-lactic acid-polyethylene block copolymer) containing recombinant human bone morphogenetic protein-2 (rhBMP-2). We previously reported the successful regeneration of bony rib and periosteum defects using beta-TCP cylinders containing 400 microg of rhBMP-2. To reduce the amount of rhBMP-2 and decrease the time required for defect repair, we utilized a biodegradable polymer carrier, in combination with rhBMP-2 and the porous beta-TCP cylinders. An 8 cm long section of rib bone was removed and replaced with an implant comprised of the porous beta-TCP cylinders and the polymer containing 80 microg of rhBMP-2. Six weeks after surgical placement of the beta-TCP cylinder/polymer/BMP-2 implants, new rib bone with an anatomical configuration and mechanical strength similar to the original bone was regenerated at the defect site. The stiffness of the regenerated ribs at 3, 6, and 12 weeks after implantation of the composite implant was significantly higher than that of ribs regenerated by implantation of rhBMP-2/beta-TCP implants. Thus, addition of the synthetic polymer to the drug delivery system for BMP potentiated the bone-regenerating ability of the implant and enabled the formation of mechanically competent rib bone. This new method appears to be applicable to the repair of intercalated long bone defects often encountered in clinical practice.  相似文献   

9.
BACKGROUND: Previous studies have demonstrated that the internal microstructure of porous calcium phosphate ceramics after the whiskering process has some changes, and obtain good mechanical properties. OBJECTIVE: To further investigate the effect of whisker-covered porous calcium phosphate ceramics in repair of canine femoral condyle defects. METHODS: Highly interconnected porous calcium phosphate ceramics was prepared by placeholder method. The whiskering of the materials was finished by hydrothermal process. Fifteen healthy adult beagle dogs were selected in this study. A 10 mm×10 mm cylindrical inclusive bone defect was made bilaterally on the lateral femoral condyle with a drill. The porous calcium phosphate ceramics after the whiskering process was implanted onto the right femoral condyle as experiment group. The porous calcium phosphate ceramics without the whiskering process was implanted onto the left femoral condyle as control group. At 2, 4, 8, and 12 weeks after implantation, X-ray and dual-energy X-ray test were conducted in the bone defect area respectively. RESULTS AND CONCLUSION: (1) X-ray: With the increase of time, the interface between bone defect and normal bone of two groups gradually blurred, disappeared, and completely fused at 12 weeks. The material in the control group was partially dissolved, while there was no obvious dissolution in the experiment group. No significant difference in the X-ray scores was found between two groups at different time points. (2) Dual-energy X-ray: With the increase of time, the bone mineral density of the two groups both increased gradually, but there was no significant difference in the bone mineral density at different time points between these two groups. These results demonstrate that the porous calcium phosphate ceramics after the whiskering process has good ability to repair the defects of femoral condyle.    相似文献   

10.
Hoshino M  Egi T  Terai H  Namikawa T  Takaoka K 《Biomaterials》2006,27(28):4934-4940
A new method to repair rib defects with biomaterials containing recombinant human bone morphogenetic protein-2 (rhBMP-2) is presented in this report. We had reported previously the successful regeneration of bony rib defects by placing a short chain of small beta-tricalcium phosphate (beta-TCP) cylinders on the intact periosteum. The multi-cylinder implants were ineffective in promoting rib repair when the periosteum was absent. By adding rhBMP-2 to the beta-TCP cylinders, we were able to promote rib bone regeneration in the presence or absence of the periosteum. The osteogenic capacity of the rhBMP-2/beta-TCP composite implant and the time required to complete regeneration were evaluated in a canine model. An 8cm long section of rib bone, including the periosteum, was removed and replaced with a chain of the rhBMP-2/beta-TCP cylinders. At 6 weeks after implantation, the ribs were restored to their original configuration and mechanical strength. The multi-cylinder beta-TCP implants were degraded and replaced by new bone in 12 weeks. This new degradable bone-inducing implant material has significant clinical potential for rib repair.  相似文献   

11.
背景:在聚乳酸-聚羟基乙酸中加入β-磷酸三钙可调控其降解速率和强度,加载骨形态发生蛋白可增强材料的诱导成骨能力。 目的:检验β-磷酸三钙/聚乳酸-聚羟基乙酸/异烟肼/骨形态发生蛋白缓释材料修复兔桡骨节段性骨缺损的效果。 方法:制作兔左侧桡骨12 mm缺损模型,随机分4组,分别于骨缺损处植入β-磷酸三钙/聚乳酸-聚羟基乙酸材料、β-磷酸三钙/聚乳酸-聚羟基乙酸/异烟肼缓释材料、β-磷酸三钙/聚乳酸-聚羟基乙酸/异烟肼/骨形态发生蛋白缓释材料,并设置空白对照组(不植入任何材料)。 结果与结论:术后12周时,β-磷酸三钙/聚乳酸-聚羟基乙酸材料组、β-磷酸三钙/聚乳酸-聚羟基乙酸/异烟肼缓释材料组、β-磷酸三钙/聚乳酸-聚羟基乙酸/异烟肼/骨形态发生蛋白缓释组骨缺损都得到较好修复,其中β-磷酸三钙/聚乳酸-聚羟基乙酸/异烟肼/骨形态发生蛋白缓释组骨缺损修复效果最佳(P < 0.05),空白对照组骨缺损未修复。表明β-磷酸三钙/聚乳酸-聚羟基乙酸/异烟肼/骨形态发生蛋白缓释材料可很好修复兔节段性骨缺损。  相似文献   

12.
背景:目前应用各种人造支架复合细胞修复骨缺损研究很多,但是各种人造支架都没有骨的天然结构,所以修复效果不够理想。 目的:将大鼠骨髓间充质干细胞接种到异种去蛋白松质骨上,移植修复大鼠股骨节段性缺损,以体内修复效果来评价复合体应用前景。 方法:分离培养大鼠骨髓间充质干细胞并进行扩增,用BrdU体外进行标记。同时制备牛去蛋白松质骨,在体外与标记后的细胞复合。制备大鼠双侧股骨中段5 mm缺损模型,实验分成3组,缺损处分别移植骨髓间充质干细胞/去蛋白松质骨复合体、单纯去蛋白松质骨及单纯骨髓间充质干细胞。 结果与结论:BrdU免疫染色结果显示,在各组细胞均呈阳性表达,但随着移植时间的延长而减弱。X射线放射学评分及苏木精-伊红染色组织学评分结果显示,各时间段复合体组成骨效果均好于其他组。复合体组Ⅰ型胶原蛋白表达随着时间的延长有明显增强,强于其他组。提示骨髓间充质干细胞复合异种去蛋白松质骨的成骨能力明显强于单纯的支架修复能力,单纯的骨髓间充质干细胞虽然有成骨能力,但不能修复节段性骨缺损。  相似文献   

13.
Synthesis of a porous bioactive ceramic implant for load bearing applications is a challenging task in maxillofacial and orthopedic surgeries. A novel bioactive resorbable silica-calcium phosphate nanocomposite (SCPC) has recently been introduced as a potential bone graft. In the present study, we employed SCPC to develop a resorbable porous scaffold and analyzed the effects of composition and porosity on the mechanical properties. The ranges of compressive strength and modulus of elasticity of SCPC containing 32-56% porosity were 1.5-50 MPa and 0.14-2.1 GPa, respectively, which matched the corresponding values for trabecular bone. The compressive strength of dense SCPC was dependent on the Si content and acquired values (93-285 MPa) comparable to that of cortical bone. The superior mechanical properties of SCPC are attributed to the intricate interactions at the boundaries of the nanograins and to the homogenous distribution of hierarchical pore-structure throughout the material volume. X-ray computed tomography and mercury porosimetry analyses revealed high interconnectivity of the pores in the size range 3 nm to 650 microm. Quantitative real-time PCR analyses showed that neonatal rat calvarial osteoblasts attached to Si-rich SCPC expressed 5- and 26-fold higher osteocalcin mRNA levels compared to cells attached to ProOsteon hydroxyapatite disks and tissue culture polystyrene plates respectively, after four days in culture. Results of the present study strongly suggest that porous, bioactive resorbable SCPCs can serve as tissue engineering scaffolds for cell delivery to treat load-bearing bone defects in orthopedic and maxillofacial surgeries.  相似文献   

14.
Zhu L  Liu W  Cui L  Cao Y 《Tissue engineering》2006,12(3):423-433
Tissue engineering can generate bone tissue and has been shown to provide a better means of repairing weight-bearing bone defect. Previous studies, however, have heretofore been limited to the use of nonosteogenically induced bone marrow stromal cells (BMSCs) or the application of slow-degradation scaffolds. In this study, weight-bearing bone was engineered using osteogenically induced BMSCs. In addition, coral was used as a scaffold material, due to its proper degradation rate for the engineering and repair of a goat femur defect. A 25 mm long defect was created at the middle of the right femur in each of 10 goats. The rates of defect repair were compared in an experimental group of ten goats receiving implants containing osteogenically induced BMSCs and in the control group of goats (n = 10) receiving just coral cylinders. In the experimental group, bony union was observed by radiographic and gross view at 4 months, and engineered bone was further remodeled into newly formed cortexed bone at 8 months. There was increased gray density of radiographic rays in the repaired area, which was significantly different (p < 0.05) from that of the control group. H&E staining demonstrated that trabecular bone was formed at 4 months. Moreover, irregular osteon was observed at 8 months. Most importantly, the tissue-engineered bone segment revealed a similarity to the left-side normal femur in terms of bend load strength and bend rigidity, showing no significant difference (p > 0.05). In contrast, the coral cylinders of the control group showed no bone formation. Furthermore, almost complete resorption of the carrier had occurred, being evident at 2 months in the control group. H&E staining demonstrated that a small amount of residual coral particle was surrounded by fibrous tissue at 4 months whereas the residues disappeared at 8 months. Based on these results, we conclude that engineered bone from osteogenically induced BMSCs and coral can ideally heal critical-sized segmental bone defects in the weight-bearing area of goats.  相似文献   

15.
背景:自体骨移植是治疗骨缺损的最理想方法,但来源有限,供区有一定的并发症,所以寻找自体骨的替代材料一直是骨科学领域的研究方向。 目的:观察珊瑚多孔羟基磷灰石、富血小板血浆和纤维蛋白胶复合物修复骨缺损的效果。 方法:在新西兰大白兔双侧前臂桡骨中段截骨1.5 cm制成骨缺损模型,随机分为3组,实验组植入珊瑚多孔羟基磷灰石、富血小板血浆和纤维蛋白胶复合物,对照组植入自体骨,空白对照组未植入任何物质。 结果与结论:①X射线:实验组术后12周时骨缺损基本修复,塑性完全,愈合过程与对照组同步;空白对照组骨缺损无明显变化。②组织病理学:实验组与对照组术后12周时骨缺损基本修复,出现成熟板层骨及哈佛氏管;空白对照组仅见大量成纤维细胞增生,未见骨质形成。③生物力学:术后2周时实验组最大扭矩和抗扭刚度优于对照组(P < 0.05),术后12周时两组最大扭矩和抗扭刚度差异无显著性意义。表明珊瑚多孔羟基磷灰石、富血小板血浆和纤维蛋白胶复合物具有促骨质愈合的作用,甚至在术后早期修复骨缺损的效果优于自体骨。  相似文献   

16.
Fu Q  Saiz E  Tomsia AP 《Acta biomaterialia》2011,7(10):3547-3554
The quest for synthetic materials to repair load-bearing bone lost because of trauma, cancer, or congenital bone defects requires the development of porous, high-performance scaffolds with exceptional mechanical strength. However, the low mechanical strength of porous bioactive ceramic and glass scaffolds, compared with that of human cortical bone, has limited their use for these applications. In the present work bioactive 6P53B glass scaffolds with superior mechanical strength were fabricated using a direct ink writing technique. The rheological properties of Pluronic® F-127 (referred to hereafter simply as F-127) hydrogel-based inks were optimized for the printing of features as fine as 30 μm and of three-dimensional scaffolds. The mechanical strength and in vitro degradation of the scaffolds were assessed in a simulated body fluid (SBF). The sintered glass scaffolds showed a compressive strength (136 ± 22 MPa) comparable with that of human cortical bone (100–150 MPa), while the porosity (60%) was in the range of that of trabecular bone (50–90%). The strength is ∼100-times that of polymer scaffolds and 4–5-times that of ceramic and glass scaffolds with comparable porosities. Despite the strength decrease resulting from weight loss during immersion in SBF, the value (77 MPa) is still far above that of trabecular bone after 3 weeks. The ability to create both porous and strong structures opens a new avenue for fabricating scaffolds for load-bearing bone defect repair and regeneration.  相似文献   

17.
背景:已有将多孔钛植入小型骨缺损的报道。 目的:验证多孔钛修复兔桡骨节段性骨缺损的疗效。 方法:成年健康新西兰大白兔 21只,建立双侧桡骨10 mm缺损模型,骨缺损处分别植入多孔钛和多孔羟基磷灰石材料。 结果:材料植入后第4,8,16周取材观察:①4周时多孔钛组和多孔羟基磷灰石组在材料与宿主骨交界处均有少量骨痂形成,第8和16周时孔隙被新生骨组织填充,与自体骨吻合好。②第8,16周时多孔钛组新骨细胞长入量和骨重建效果几乎接近多孔羟基磷灰石组。两组骨面积在新生骨质长入量上差异无显著性意义(P > 0.05)。③第8,16周时多孔钛组的最大承载负荷值明显优于多孔羟基磷灰石组。表明多孔钛支架材料可以促进新骨的形成并有利于节段骨缺损的修复。  相似文献   

18.
背景:探讨医用硫酸钙人工骨可替代同种异体骨作为骨缺损的修复材料的可行性。 目的:观察医用硫酸钙人工骨材料治疗良性骨肿瘤骨缺损的临床疗效。 方法:纳入应用医用硫酸钙人工骨材料于临床修复良性骨肿瘤刮除术后骨缺损病例31例和同种异体骨材料修复病例36例。观察植入材料后4,8,12周摄X射线片植骨吸收情况及植骨材料降解率。 结果与结论:全部病例均获随访3个月以上。两组病例在随访期间植骨材料降解率差异无显著性意义。良性骨肿瘤植骨区无复发。患者植入材料后3个月X射线片示骨缺损部位有新骨生成。结果表明医用硫酸钙人工骨材料临床疗效和同种异体骨接近。  相似文献   

19.
A bone scaffold material (nano-HA/ collagen/PLA composite) was developed by biomimetic synthesis. It shows some features of natural bone both in main composition and hierarchical microstructure. Nano-hydroxyapatite and collagen assembled into mineralized fibril. The three-dimensional porous scaffold materials mimic the microstructure of cancellous bone. Cell culture and animal model tests showed that the composite material is bioactive. The osteoblasts were separated from the neonatal rat calvaria. Osteoblasts adhered, spread, and proliferated throughout the pores of the scaffold material within a week. A 15-mm segmental defect model in the radius of the rabbit was used to evaluate the bone-remodeling ability of the composite. Combined with 0.5 mg rhBMP-2, the material block was implanted into the defect. The segmental defect was integrated 12 weeks after surgery, and the implanted composite was partially substituted by new bone tissue. This scaffold composite has promise for the clinical repair of large bony defects according to the principles of bone tissue engineering.  相似文献   

20.
Hydroxyapatite (HA) is a fundamental mineral-based biomaterial, used for preparing composites for bone repair and regeneration. Gelatin blended with starch results in scaffold composites with enhanced mechanical properties. A gelatin-starch blend reinforced with HA nanocrystals (nHA) gave biocompatible composites with enhanced mechanical properties. In this study, a porous scaffold of gelatin-starch-nHA composites was fabricated through microwave vacuum drying and crosslinking using trisodium citrate. Three different composite scaffolds were prepared at three different percentages of nHA: 20%, 30% and 40%. The microstructures and compositions of the composites were analyzed. Within the porous structure, the nHA crystals were observed to precipitate. The interaction between the gelatin-starch network film and nHA crystalline material was studied using Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction analysis (XRD). XRD reflections showed that there are two different minerals present in the scaffold composite. There were strong reflection peaks close to the 26 degrees and 32 degrees 2theta angles of HA, and close to the 8 degrees and 49 degrees 2theta angles for sodium citrate minerals. The FTIR result suggested that carboxyl groups, C=O and amino groups play crucial roles in HA formation on the surface of a gelatin network.  相似文献   

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