不同温度煅烧骨作骨形态发生蛋白载体的试验研究

采用不同温度天然煅烧骨与骨形态发生蛋白复合物进行兔桡骨骨缺损修复的动物试验。发现600℃的煅烧骨与骨形态发生蛋白的复合材料（BMP／SB）与900℃及1200℃的BMP／SB材料在诱导成骨及修复骨缺损中作用不如后两者。900℃及1200℃的BMP／SB材料在新骨形成量上要高于600℃的BMP／SB材料（P〈0．05），而后两者间无明显差别（P〉0.05）。但900℃的煅烧骨材料力学强度大，制备温度相对低，故经济效益明显。研究提示900℃的的煅烧骨与600℃、1200℃的煅烧骨相比，更适于用作骨形态发生蛋白的载体。     

纳米羟基磷灰石/重组人骨形成蛋白-2复合人工骨的实验研究

目的：探讨纳米羟基磷灰石复合重组人骨形成蛋白-2人工骨（Nano-HA／rhBMP-2）的骨缺损修复能力，为临床骨缺损修复提供依据。方法：采用新西兰大白兔75只，单侧桡骨制备骨缺损动物模型，以Nano-HA／rhBMP-2复合人工骨植入骨缺损处进行修复作为实验组（A组），以Nano-HA人工骨（B组）及空白组（C组）作为对照组；术后4周、8周、12周分别行大体标本观察、X线、扫描电镜（SEM）、放射性核素骨扫描（ECT）及生物力学测试，综合评价Nano-HA／rhBMP-2复合人工骨对骨缺损的修复能力及对机体的影响。结果：Nano-HA／rhBMP-2复合人工骨、Nano-HA人工骨均可促进新骨形成，前者新骨形成量大，骨缺损修复能力明显优于后者，差异有统计学意义（P〈0．05）。结论：Nano-HA／rhBMP-2复合人工骨具有良好的骨缺损修复能力，可望成为一种理想的骨缺损修复材料。     

自固化磷酸钙人工骨的生物学安全性试验研究

本文报告了自固化磷酸钙（CPC）人工骨的遗传毒性试验及动物体内植入实验结果：体外试验采用CPC的浸出液,试验项目包括Ames试验,微核试验及UDS试验,体仙实验包括骨内植入肌肌肉内植入实验,结果表明,CPC浸出液对体细胞的遗传物质无损害作用,无致基因突变的作用,植入体内后,只出现一过性的炎症反应,无异物反应,CPC与骨形成直接的骨性愈合,其溶解形成的钙,磷颗粒经髓腔或哈氏管系统运输,结果是CPC具有良好的生物相容性,适合于作为骨缺损的填充材料。     

BMP2活性多肽/PLGA复合物植入异位成骨的实验研究

目的用动物实验的方法评价自行研制合成的BMP2活性多肽生物因子与可降解PLGA复合物的异位诱导成骨能力。方法实验分3组。A组：BMP2活性多肽／PLGA复合物组；B组：单纯PLGA组；C组：明胶海绵组。分别于Wistar大鼠背部两侧骶棘肌下包埋植入。术后1、4、8和12周取材。经组织学观察和CT三维成像比较成骨情况，western blot检测Ⅰ型胶原及骨桥蛋白的蛋白表达，了解异位成骨的情况。结果植入块周围初期均表现为急性炎症反应，后期均为淋巴细胞、巨噬细胞浸润为主的非特异性炎症反应。A组植入4周时植入区有软骨生成，8周时有活跃的成骨细胞出现，并有非编织骨结构。12周可见大量新骨形成，有典型的骨小梁新生血管结构。B组和C组12周时仅见纤维组织形成，未见成骨。结论人工合成的BMP2活性多肽体内能启动软骨化骨过程，具有较强的异位诱导成骨能力。有与天然BMP2类似的骨诱导活性，具有广阔的应用前景。     

纳米羟基磷灰石人工骨修复骨缺损的实验研究

目的：探讨多孔Nano-Hydmxyapatite（Nano-HA）人工骨的骨缺损修复作用及相关问题，为临床骨缺损修复提供依据。方法：采用新西兰大白兔39只，单侧桡骨制备骨缺损动物模型，用多孔Nano-HA人工骨材料植入骨缺损处进行修复作为实验组，以HA人工骨材料及空白组作为对照组；术后4、8、12周分别行大体标本观察、组织学、X线、扫描电镜及生物力学测试，综合评价多孔Nano-HA人工骨对骨缺损的修复能力及对机体的影响。结果：Nano-HA人工骨和HA人工骨均可促进新骨形成，前者新骨形成量大，骨缺损修复能力明显优于后者，差异有显著性（P〈0．05）。结论：Nano-HA人工骨具有良好的成骨能力和生物相容性，可望成为一种理想的骨缺损修复材料。     

医用硫酸钙人工骨与同种异体骨修复良性骨肿瘤骨缺损的对比分析

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。     

硅胶膜管联合BMP／HA修复大块骨缺损实验研究

目的：探讨硅胶膜（SGM）管与骨形态发生蛋白（BMP）和羟基磷灰石（HA）复合的修复兔长骨缺损的效果。方法：制备兔桡骨中段1．2cm缺损模型,实验组缺损区外围包绕硅胶膜,其内分别填充自体骨,BMP／HA,HA三种材料：对照组仅填充HA;空白组骨缺损区未填充,通过X线摄片,光学显微镜,立体计量学分析和生物力学评价对骨缺损区愈合效果进行.分析。结果：术后1个月,SGM＋BMP／HA组骨缺损区见有大量的类骨质,明显优于其他组,第2个月,SGM＋自体骨组与SGM＋BMP／HA组植入区有大片新骨形成,术后3个月,SGM＋自体骨级瑟SGM＋BMP／HA组骨缺损基本修复并出现骨组织改建现象,此时,SGM＋HA组与对照组骨缺损区也有少量新骨形成,空白缺损区为纤维组织充填,结论：硅胶膜管与自体骨或BMP／HA联合用于修复骨缺损成骨效果更佳,因为硅胶膜的屏障作用可使骨缺损区受到引导成骨和放导成骨的双重作用。     

骨形成蛋白复合人工骨的研究进展

骨形成蛋白 (bone m orphogenetic protein,BMP)是一种广泛存在于各种动物骨组织中的低分子糖蛋白多肽 ,能诱导未分化的间充质细胞或骨髓基质细胞不可逆地分化为软骨和骨 ,从而导致新骨形成。经长期实验及临床观察发现 ,对于相对较小的骨缺损 ,单独植入 BMP可以达到较好的修复效果 ,但由于 BMP产量低、植入体内吸收快 ,不能在有效的时间内作用于更多的靶细胞 ,对较大的骨缺损不能提供支架作用。为解决这些问题 ,国内外学者积极研究以寻找充当BMP缓解载体并能发挥支架作用的材料。经大量的研究发现 〔1 ,2〕,较理想的 BMP复合材料应具…     

携载rhBMP-2微球的新型复合人工骨的制备及生物相容性研究

目的制备一种具有良好生物相容性、降解性和成骨活性、可注射的自凝固新型骨修复材料。方法采用复乳溶剂挥发方法制备携载rhBMP-2的聚乳酸与聚乙醇酸共聚物（PLGA）微球，并将其与rhBMP-2／磷酸钙骨水泥（CPC）复合，制备出rhBMP-2／PLGA微球／CPC复合人工骨。探讨材料特性包括形貌和体外rhBMP-2释放速度，采用体外细胞培养的方法测定复合材料的细胞黏附能力及其浸提液对于人骨髓基质干细胞（MSCs）增殖和成骨分化的影响。结果与单纯rhBMP-2／CPC材料相比较，复合材料rhBMP-2体外释药明显提高。材料与MSCs可良好黏附并使其增殖。体外培养时材料不同时间的浸提液对MSCs细胞的增殖具有促进作用，对于细胞成骨分化的影响与单纯CPC无明显差别。结论rhBMP-2／PLGA微球／磷酸钙骨水泥新型复合人工骨具有良好的生物相容性和活性因子缓释功能，是一种有良好应用前景的骨修复材料。     

成骨诱导脂肪基质细胞在骨组织工程体内成骨中的作用

背景：以往研究认为,经过成骨诱导后的脂肪基质细胞通过转化为成骨细胞分泌骨基质进而修复骨缺损,然而并没有明确结论证实。 目的：将经过体外成骨诱导的脂肪基质细胞复合支架材料分别植入骨缺损区和非骨区,根据是否成骨,验证经过成骨诱导后的脂肪基质细胞是否转化为成骨细胞。 方法：取12月龄犬背部皮下脂肪,经胶原酶消化法获得单个核细胞,将培养的第3代细胞与双相磷酸钙陶瓷形成复合物。在犬下颌骨两侧制备长20 mm、高10 mm的箱状缺损,拔除术区牙齿,将细胞支架复合物植入一侧术区,空白侧留作对照;另外在犬背部皮下肌肉区植入细胞支架复合物及骨诱导性磷酸钙陶瓷材料,术后6周及12周经组织学检测骨缺损修复情况。 结果与结论：脂肪基质细胞复合双相磷酸钙陶瓷在骨缺损区成骨,在肌肉区未形成新骨;骨诱导性磷酸钙陶瓷在肌肉区形成新骨。提示成骨诱导并不能将脂肪基质细胞转化为成骨细胞,其确切机制有待进一步研究。     

Long-term variations in mechanical properties and in vivo degradability of CPC/PLGA composite

A new type of bone cement composite was successfully achieved by mixing degradable biosecure polylactic-co-glycolic acid (PLGA) fibers with high initial strength calcium phosphate cement (CPC). Its higher initial strength was mainly responsible for the in situ reinforcing effect of residual tetra-calcium phosphate monoxide (r-TTCP) particles reported in our previous work. So this bone cement composite containing fibers and the controlling group could be termed as CPC/PLGA composite and pure CPC or fiber-free group, respectively. In this study, we had investigated mechanical properties and microstructures of the CPC/PLGA composite immersed in 0.9% saline solution for different time and its in vivo degradation behaviors after implanting in rabbit muscle and femur bone, respectively. Results showed that the incorporation of the degradable fibers not only greatly increased the initial toughness and flexural strength of the CPC/PLGA composite but also significantly improved its later osteo-conduction as well as degradation rate. The rabbit muscle implant tests showed that the weight loss ratio of the CPC/PLGA composite increased by 41.03% as compared to the pure CPC. And the rabbit femur implant tests showed that the composite exhibits outstanding biocompatibility and bioactivity and more excellent osteoconduction and degradability than the pure CPC.     

Injectable calcium phosphate cement with PLGA, gelatin and PTMC microspheres in a rabbit femoral defect

In this study, we investigated the in vivo degradation properties and tissue response towards injectable calcium phosphate cement (CPC) with no further addition, or calcium phosphate composite cement containing approximately 50 vol.% of microspheres. Three types of spheres were assessed, i.e. poly(lactic-co-glycolic acid) (PLGA), gelatin (GEL) and poly(trimethylene carbonate) (PTMC). The cements were injected into 4.6 mm diameter and 6mm deep cylindrical defects in the femoral condyle of New Zealand white rabbits, hardened in situ and, after wound closure, left to heal for 4, 8 and 12 weeks (n=6 for each composition and time period). After retrieval, specimens were analyzed using histological and histomorphometrical methods. Results showed that non-modified CPCs showed excellent bone contact but only very limited erosion at the surface. The CPC/PLGA implant degraded almost completely, while tissue response significantly improved at each time period. CPC/PTMC showed slower degradation characteristics compared to CPC/PLGA. Finally, at all time periods, there was an evident inflammatory response to the CPC/GEL composite cement. In conclusion, the degradation properties of the CPC/PLGA microspheres composite and its bone response when implanted into the femoral condyles of rabbits were significantly better than those of CPC/gelatin and CPC/PTMC microspheres composites.     

In vitro and in vivo study of calcium polyphosphate fiber/calcium phosphate cement/micromorselized bone composite for bone defect repair

The aim of this study was to develop a superior bone engineering material for repair of bone defects. A composite of calcium polyphosphate fiber (CPPF)/calcium phosphate cement (CPC)/micromorselized bone was prepared. A scanning electron microscope was used to observe the structure of the composite and measure its porosity. Seventy-two pieces of the material were placed in phosphate buffer solution and changes in pH were measured over time, and compressive strength was also measured. In vivo experiments were carried out on 72 rabbits divided into six groups: bone implantation with CPPF/CPC/micromorselized bone, CPC/micromorselized bone, micromorselized bone, CPPF/CPC, CPC, respectively; and no implantation (control). The implants were assessed with X-ray film and histologically, and bone density and biomechanical strength were measured. The study period was 12 weeks. The addition of CPPF increased apertures of the composite. The bone defects in the CPPF/CPC/micromorselized group compared with the other groups had significantly higher radiographic grading and significantly greater bone density (p < 0.05) and biomechanical strength (p < 0.05). The new composite improves the speed and quality of bone formation. The addition of CPPF improved the mechanical properties of the scaffold material and created higher porosity.     

磷酸钙骨水泥复合骨形态发生蛋白6和血管内皮生长因子修复骨缺损

背景：单独将骨形态发生蛋白或血管内皮生长因子植入体内易被血液冲刷掉而不能最大限度发挥诱导成骨和血管生成作用,同时缺少载体的支撑作用。 目的：观察骨形态发生蛋白6、血管内皮生长因子及磷酸钙骨水泥联合应用在骨缺损修复过程中的作用。 方法：制作新西兰兔双侧股骨内侧髁骨缺损模型,左侧分别植入磷酸钙骨水泥/骨形态发生蛋白6/血管内皮生长因子、磷酸钙骨水泥/骨形态发生蛋白6及磷酸钙骨水泥,右侧不植入任何物质作为空白对照。植入8,16周通过硬组织切片组织学观察、电镜扫描等手段观察新骨形成情况。 结果与结论：各组材料的组织相容性良好,未见明显炎症组织反应。植入8周时,磷酸钙骨水泥/骨形态发生蛋白6/血管内皮生长因子组骨水泥-骨组织交界处基本上被新生骨小梁包绕,材料进一步降解,新生骨小梁表面可见大量活跃的成骨细胞;16周时,新生骨小梁继续长入,进一步增长、增粗、增多,有大量新生编织骨成网格状长入材料中,骨水泥材料降解明显,与周围组织结合紧密,降解与骨长入同步,此组不同时间点成骨速度及成骨效果均明显优于其他两组材料(P < 0.05)。表明3种材料联合应用可协同促进骨缺损修复。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：     

In vivo bone response to porous calcium phosphate cement

We conducted an in vivo experiment to evaluate the resorption rate of a calcium phosphate cement (CPC) with macropores larger than 100 microm, using the CPC called Biocement D (Merck Biomaterial, Darmstadt, Germany), which after setting only shows pores smaller than 1 microm. The gas bubble method used during the setting process created macroporosity. Preset nonporous and porous cement implants were inserted into the trabecular bone of the tibial metaphysis of goats. The size of the preset implants was 6 mm and the diameter of the drill hole was 6.3 mm, leaving a gap of 0.3 mm between implant surface and drill wall. After 2 and 10 weeks, the animals were euthanized and cement implants with surrounding bone were retrieved for histologic evaluation. Light microscopy at 2 weeks revealed that the nonporous implants were surrounded by connective tissue. On the cement surface, we observed a monolayer of multinucleated cells. Ten weeks after implantation, the nonporous implants were still surrounded by connective tissue. However, a thin layer of bone now covered the implant surface. No sign of cement resorption was observed. In contrast, the porous cement evoked a completely different bone response. At 2 weeks, bone formation had already occurred inside the implant porosity. Bone formation even appeared to occur as a result of osteoinduction. Also, at their outer surface, the porous implants were completely surrounded by bone. At 2 weeks, about 31% of the initial cement was resorbed. After 10 weeks, 81% of the initial phosphate cement was resorbed and new bone was deposited. On the basis of these observations, we conclude that the creation of macropores can significantly improve the resorption rate of CPC. This increased degradation is associated with almost complete bone replacement.     

负载骨形态发生蛋白新型骨填充材料应用于椎体成形

背景：磷酸钙骨水泥克服了聚甲基丙烯酸甲酯的诸多缺点并具有良好的生物相容性。而负载复合重组人类骨形态发生蛋白2的磷酸钙骨水泥经固化后可具有微孔结构,可提高经皮椎体成形充填材料的临床价值。 目的：探讨以可注射型磷酸钙骨水泥和纤维蛋白胶作为共同载体,复合重组人类骨形态发生蛋白2,替代聚甲基丙烯酸甲酯应用于新西兰大白兔椎体成形的可行性。 方法：制备磷酸钙骨水泥/纤维蛋白胶/复合重组人类骨形态发生蛋白2新型复合材料。采用小鼠肌袋异位诱导成骨模型对不同植入材料进行骨诱导活性评价;模仿椎体成形观察新型复合材料和聚甲基丙烯酸甲酯植入兔椎体后的生物力学改变。 结果与结论：新型复合材料植入后2,4周碱性磷酸酶水平最高,植入后4周软骨细胞逐渐成熟,新骨形成,抗压强度和抗扭转强度明显低于正常椎体和聚甲基丙烯酸甲酯植入后(P < 0.05),8周后材料被进一步降解,抗压强度和抗扭转强度均有所上升,扛扭转强度与正常椎体相比无显著差别,但仍明显低于聚甲基丙烯酸甲酯(P < 0.05)。microCT提示其新生骨形成多而早,但聚甲基丙烯酸甲酯未见材料吸收及周围骨质长入。说明新型复合材料植入椎体后能够获得良好的骨诱导和骨传导功能,材料降解和新骨替代同步,接近于正常椎体的骨愈合,可望替代聚甲基丙烯酸甲酯应用于椎体成形。     

磷酸钙骨水泥/纤维蛋白胶复合材料填充桡骨缺损的生物相容性

BACKGROUND: The chemical compositions and structure of calcium phosphate bone cement are similar to those of human bone, which can fill the bone collapse caused by fracture and induce osteogenesis, but its degradation rate is slow. OBJECTIVE: To evaluate the biocompatibility of the calcium phosphate cement/fibrin glue and the feasibility of repairing radius defects. METHODS: In vitro cytotoxicity experiment: Mouse fibroblasts were cultured in the calcium phosphate bone cement/fibrin glue extracts, phenol solution, and RPMI 1640 culture medium containing 10% fetal bovine serum, respectively, to detect the cytotoxicity grade. Hemocompatibility experiment: Calcium phosphate bone cement/fibrin glue extracts, normal saline and distilled water were respectively added into the rabbit anticoagulation, to detect the hemolytic rate. Forty-five New Zealand white rabbits were enrolled and modeled into bilateral radius defects, followed by randomly allotted into three groups: blank control group without any intervention, experimental and control groups were given the implantation with calcium phosphate bone cement/fibrin glue and autologous radius, respectively. X-ray, histology, bone mineral density and biomechanical test were performed at postoperative 4, 8 and 16 weeks. RESULTS AND CONCLUSION: The toxicity grade of the calcium phosphate cement/fibrin glue was 0 to 1. The hemolytic rate of the calcium phosphate cement/fibrin glue was 3.15%. At 16 weeks postoperatively, X-ray showed that in the experimental and control groups, the fracture line disappeared completely, pulp cavity was recanalized, and in plastic completely. Histology showed that the reconstructed bone trabecular was obvious, plate layer of bone was mature, and medullary cavity recanalization appeared in the control group; there were a large number of new grid-shaped woven bone tissues growing into the material in the experimental group, with overt degradation, and degradation rate was in parallel to bone ingrowth. The bone density, the maximum load, maximum stress and failure energy in the experimental and control groups were significantly higher than those in the blank control group (P < 0.05), and all above indicators showed no significant differences between the experimental and control groups. These results manifest that the calcium phosphate bone cement/fiber protein glue composite material holding a good biocompatibility can promote bone tissue regeneration for bone defect repair, achieving similar curative effect with autologous bone transplantation.     

自固化磷酸钙人工骨(CPC)修复骨肿瘤骨缺损的初步临床应用

评价自固化磷酸钙人工骨（CPC）治疗骨肿瘤缺损早期临床效果。方法对23例骨瘤患者行病灶刮除、国产CPC填塞修补术。患者年龄8～45岁，平均24.3岁。术后血液免疫学及X线检查，随访1～2年。结果CPC固化时间在15～30min，平均20min。临床使用后未见明显局部和全身不良反应，6个月后逐渐出现降解。随访X线片示CPC与宿主骨直接愈合，与原骨界面间接触紧密无间隙，骨缺损处解剖形状完全恢复。     

Bioresorption behavior of tetracalcium phosphate-derived calcium phosphate cement implanted in femur of rabbits

One primary focus of the present study was to clarify the crucial resorption-location relationship of a recently developed single-phase TTCP-derived calcium phosphate cement (CPC) implanted in rabbit femur in a systematic and quantitative way. Gross examination of retrieved CPC/bone composite samples indicated that the CPC implant did not evoke inflammatory response, necrosis or fibrous encapsulation in surrounding bony tissues. Histological examination revealed excellent CPC-host bone bonding. At 4 weeks, the resorption-induced voids between terminals of bone defects and implants were largely filled with new bone. CPC resorption, new blood vessels, osteocytes, osteons and osteoblast-like cells lining up with active new bone were observed at remodeling sites. At 12 weeks, a new bone network was developed within femoral defect, while CPC became islands incorporated in the new bone. At this stage, crevices filled with lamellar new bone structure were frequently observed. At 24 weeks, bone ingrowth and remodeling activities became so extensive that the interface between residual cement and new bone became less identifiable. In general, at all implant locations the resorption ratio values increased with implantation time, while at all implantation times the resorption ratios decreased from the exterior (cortical site) to the interior (cancellous site) of implants. At the end of 24 weeks, CPC was almost completely resorbed and bone remodeling almost finished at the cortical site.     

Of the in vivo behavior of calcium phosphate cements and glasses as bone substitutes

The use of injectable self-setting calcium phosphate cements or soluble glass granules represent two different strategies for bone regeneration, each with distinct advantages and potential applications. This study compares the in vivo behavior of two calcium phosphate cements and two phosphate glasses with different composition, microstructure and solubility, using autologous bone as a control, in a rabbit model. The implanted materials were alpha-tricalcium phosphate cement (cement H), calcium sodium potassium phosphate cement (cement R), and two phosphate glasses in the P(2)O(5)-CaO-Na(2)O and P(2)O(5)-CaO-Na(2)O-TiO(2) systems. The four materials were osteoconductive, biocompatible and biodegradable. Radiological and histological studies demonstrated correct osteointegration and substitution of the implants by new bone. The reactivity of the different materials, which depends on their solubility, porosity and specific surface area, affected the resorption rate and bone formation mainly during the early stages of implantation, although this effect was weak. Thus, at 4 weeks the degradation was slightly higher in cements than in glasses, especially for cement R. However, after 12 weeks of implantation all materials showed a similar degradation degree and promoted bone neoformation equivalent to that of the control group.