磷酸钙骨水泥的改性研究进展

磷酸钙骨水泥作为一种新型人工骨替代材料,以其良好的生物相容性和骨传导性被广泛应用于临床骨缺损修复。但其存在固化时间较长、机械性能不足及降解缓慢等缺点,使其应用受到一定限制,故需要对其进行改性研究,本就此做一综述如下。     

磷酸钙骨水泥的生物学研究进展

本综述了磷酸钙骨水泥作为一种新型人工骨替代材料近年来的生物学基础及提高其生物学性能的研究,阐明了磷酸钙骨水泥以其良好的生物学特性,使其在骨缺损修复领域具有广阔的应用前景。     

磷酸钙骨水泥的生物学研究进展

本文综述了磷酸钙骨水泥作为一种新型人工骨替代材料近年来的生物学基础及提高其生物学性能的研究 ,阐明了磷酸钙骨水泥以其良好的生物学特性 ,使其在骨缺损修复领域具有广阔的应用前景。     

钙与骨代谢

一、钙在骨代谢的重要性（一）骨的成分：骨由胶原及其他蛋白质与骨细胞构成骨小梁和骨皮质，骨小梁和骨皮质形成了骨的支架，确定了骨的形状，大小和结构。骨盐沉着于上述骨质结构，增加其硬度。骨盐中最主要的是钙、磷、镁，还有少量的微量元素。体内总钙量为１０００ｇ...     

8例骨恶性巨细胞瘤的病理组织学观察

骨恶性巨细胞瘤(Malignant gaint cell tumor of bone,以下简称MGCT)是一种少见的骨恶性肿瘤。文献报告其发病率占骨恶性肿瘤的0.5%,占骨巨细胞瘤的7.5%。现将我院从1955年至1984年41例骨巨细胞瘤中经病理证实的8例MGCT重新作了病历及病理组织学复查,并结合文献着重讨论其组织学改变及鉴别诊断。     

骨形态形成蛋白载体与可控释放系统的研究进展

骨形态形成蛋白(BMPs)是目前已知的诱导骨生成能力最强的因子之一。重组人骨形态形成蛋白(rhBMPs)的产品已经在骨科、口腔医学等领域得到广泛应用。临床使用时,需要将其与具有缓释作用的载体复合,保持作用部位的浓度以持续诱导成骨。本文就BMPs载体及其释放系统的研究进展作一综述。     

重组人骨形态发生蛋白2-肝素-人工骨复合材料的骨诱导活性

背景：已有将重组人骨形态发生蛋白2应用于骨再生及修复的报道,但由于其在生物体内半衰期短而导致诱导骨形成的能力受到限制。 目的：制备具有较好缓释效果的重组人骨形态发生蛋白2-肝素-人工骨复合材料,并检测其缓释性能及骨诱导活性。 方法：通过高效液相色谱法检测重组人骨形态发生蛋白2-肝素复合物对于酶解的保护作用。将重组人骨形态发生蛋白2与肝素溶液混匀后复合于人工骨材料表面,ELISA方法检测其体外释药性质,茜素红染色法检测其诱导成骨细胞的能力,应用小鼠体内实验评价其异位骨诱导能力。 结果与结论：成功制备了具有良好缓释效果的重组人骨形态发生蛋白2-肝素-人工骨复合材料,具有较强的诱导骨钙蛋白及异位骨形成能力。     

镁离子促进骨再生的分子机制

背景:近年来,镁离子良好的促进骨再生的作用已得到了实验和临床的广泛认可,含镁植入材料被广泛应用于骨再生,其促进骨再生的分子机制涉及骨环境中的多种细胞及细胞因子,但尚未完全明晰.目的:文章对镁离子促进骨再生的分子机制作一综述.方法:以"magnesium OR magnesium ion""bone regenerati...     

护骨素的研究进展

护骨素是近年发现的肿瘤坏死因子家族的新成员具有犯制破骨细胞分化及骨吸收活性的一种分泌型糖蛋白。护骨素与其护骨素配基之间竞争性结合机制是调控破骨细胞分化、增殖、凋亡及发挥重作用过程中最重要的信号通路,是雌激素调节破骨细胞生成和抗骨吸收的作用途径之一。对其研究将促进因破骨细胞活性增强导致骨吸收、骨破坏为特点的疾病的病因、预防和治疗等研究的深入。     

破骨细胞的生物学新观

骨是一种不断进行重建的有活力组织。骨重建 (remodeling)是一个偶联过程 ,骨吸收紧随新骨形成。负责骨吸收的细胞主要是多核破骨细胞 ,关于调节破骨细胞的形成及溶骨作用的因子还有许多问题未找到答案 ,但最近在理解破骨细胞的细胞生物学和分子生物学及骨髓微环境在调节破骨细胞的形成及溶骨作用方面已获得了重大进展。1　破骨细胞形态学破骨细胞 osteoclast)是一种大的多核巨细胞 ,含 2～ 1 0 0个核 ,通常为 1 0～ 2 0个 ,直径可达 1 0 0 μm,数量极少 ,通常仅 2～ 3个 /μm3,但在骨转换活跃的部位 ,如成长中骨的干骺端 ,其数量增加。破骨…     

一种可注射体内成孔的磷酸钙骨水泥

背景：磷酸钙骨水泥存在脆性大、抗水溶性(血溶性)差、力学性能不足、降解缓慢等缺点,其临床应用受到一定限制,故需要对其进行改性研究。 目的：制备一种具有一定强度、孔隙率、适合骨生长的多孔磷酸钙骨水泥生物支架材料。 方法：以磷酸钙骨水泥为基本体系,液相采用壳聚糖的弱酸溶液,以提高磷酸钙骨水泥的可塑性和黏弹性,使骨水泥具有可注射性,显著提升骨水泥的应用范围及应用舒适度。固相为双相磷酸钙(磷酸四钙+磷酸氢钙)粉体,并在固相中添加一定量的甘露醇及聚乳酸-乙醇酸共聚物作为造孔剂,制备磷酸钙支架材料。 结果与结论：此材料孔径可达到10~300 μm。添加60%致孔剂时,磷酸钙骨水泥固化体孔隙率可达到(68.3±1.5)%。磷酸钙骨水泥孔隙率的增加使材料的力学性能下降,其抗压强度从最初不含致孔剂时的(53.0±1.4) MPa下降到含60%致孔剂的(2.5±0.2) MPa。实验制备的此种多孔磷酸钙骨水泥材料,是具有一定抗压强度、较好的孔隙率,并能体内降解的可注射生物支架材料。     

Long-term outcome of cryopreserved bone-derived osteoblasts for bone regeneration in vivo

Cryopreserved bone-derived osteoblasts (CBOs) have been considered as a promising cell source for bone regeneration. Previous studies have demonstrated that CBOs had good proliferation and osteogenicity. However, the long-term outcome of CBOs in vivo still remains unknown. In this experiment, we applied CBOs combined with calcium phosphate cement (CPC) to augment maxillary sinus in canine, computer tomography, polychrome labeling, biomechanical tests, fluorescent immunohistochemistry staining and histological analysis were used to analyze the property and mineralization process of the tissue-engineered bone preclinical application. Our results showed that CBOs combined with CPC could promote bone regeneration, dramatically maintain the height, volume and biomechanical property of augmented maxillary sinus. Furthermore, the tissue-engineered bone was more mature than scaffold alone or autogenous bone, and bone formation and remodeling were still apparent 20 months postoperatively. Additionally, 4 months after surgery might be the suitable time point for implants placement in the regenerated bone. These results also indicate that cryopreserved bone may be a potential source of osteoblasts for maxillary sinus augmentation.     

磷酸钙骨水泥药物缓释载体研究进展

本文综述了磷酸钙骨水泥作为药物缓释载体系统在载药前后的特征变化、药物缓释的动力学曲线及其影响因素 ,阐明该系统在临床骨缺损修复中具有一定的应用价值     

Quantitative analysis of the resorption and osteoconduction process of a calcium phosphate cement and its mechanical effect for screw fixation

The clinical application of calcium phosphate cements (CPCs) composed of tetracalcium phosphate and dicalcium phosphate anhydrous has been limited because of its longer setting time, so that we developed the CPC in which the setting time was shortened to approximately 10 min. Aiming at clinical application, we evaluated the histological response in the bone quantitatively and the biomechanical effectiveness of this substance. The CPC was implanted in the rabbit femoral condyle up to 52 weeks for histological evaluation. In mechanical testing, small cancellous screws were inserted into the condyle, both with and without augmentation with the CPC, and the pull-out strength was measured. The micro-computed tomography finding demonstrated that the cross-sectional area of the implanted CPC at 24 weeks was approximately two-thirds of the initial area. The amount of newly calcified bone around the CPC was significantly greater than that of the sintered hydroxyapatite. Histologically, the new bone was formed on the surface of the implanted CPC 1 week after the implantation and resorption of the CPC was evident at 3 weeks. The pull-out strength was enhanced significantly by augmentation with the CPC and the initial strength was maintained for a 6 week period. This CPC showed good osteoconductivity and was resorbed without adverse inflammation. Using the CPC as augmentation may be capable of useful treatment options in fractures with poor bone quality.     

妥布霉素对磷酸钙骨水泥性能的影响

本文研究了载有妥布霉素的磷酸钙骨水泥体系的应用性能 ,包括体系的凝结时间、抗压强度、水化产物及微结构分析。结果表明 ,药物的引入并未影响材料水化产物的组成。随着药物含量的提高 ,凝结时间延长 ,抗压强度下降 ,这是由于药物的存在导致了骨水泥颗粒间的反凝聚。但材料在模拟体液中静置一周后 ,强度比缓释前均有不同程度提高 ,并趋于 36MPa,同时呈经沉淀 溶解 再水化过程形成的针状水化产物生成。这些结果将对该体系材料的临床应用具有指导作用     

Fiber reinforced calcium phosphate cements -- on the way to degradable load bearing bone substitutes?

Calcium phosphate cements (CPC) are well-established materials for the repair of bone defects with excellent biocompatibility and bioactivity. However, brittleness and low flexural/tensile strength so far restrict their application to non-load bearing areas. Reinforcement of CPC with fibers can substantially improve its strength and toughness and has been one major strategy to overcome the present mechanical limitations of CPC. Fiber reinforced calcium phosphate cements (FRCPC) thus bear the potential to facilitate the use of degradable bone substitutes in load bearing applications. This review recapitulates the state of the art of FRCPC research with focus on their mechanical properties and their biological evaluation in?vitro and in?vivo, including the clinical data that has been generated so far. After an overview on FRCPC constitutes and processing, some general aspects of fracture mechanics of reinforced cementitious composites are introduced, and their importance for the mechanical properties of FRCPC are highlighted. So far, fiber reinforcement leads to a toughness increase of up to two orders of magnitude. FRCPC have extensively been examined in?vitro and in?vivo with generally good results. While first clinical products focus on the improved performance of FRCPC with regard to secondary processing after injection such as fixation of screws and plates, first animal studies in load bearing applications show improved performance as compared to pure CPCs. Aside of the accomplished results, FRCPC bear a great potential for future development and optimization. Future research will have to focus on the selection and tailoring of FRCPC components, fiber-matrix compatibilization, integral composite design and the adjusted degradation behavior of the composite components to ensure successful long term behavior and make the composites strong enough for application in load bearing defects.     

Biocompatibility and resorption of a radiopaque premixed calcium phosphate cement

Calcium phosphate cements (CPC) are used as bone void filler in various orthopedic indications; however, there are some major drawbacks regarding mixing, transfer, and injection of traditional CPC. By using glycerol as mixing liquid, a premixed calcium phosphate cement (pCPC), some of these difficulties can be overcome. In the treatment of vertebral fractures the handling characteristics need to be excellent including a high radio-opacity for optimal control during injection. The aim of this study is to evaluate a radiopaque pCPC regarding its resorption behavior and biocompatibility in vivo. pCPC and a water-based CPC were injected into a ? 4-mm drilled femur defect in rabbits. The rabbits were sacrificed after 2 and 12 weeks. Cross sections of the defects were evaluated using histology, electron microscopy, and immunohistochemical analysis. Signs of inflammation were evaluated both locally and systemically. The results showed a higher bone formation in the pCPC compared to the water-based CPC after 2 weeks by expression of RUNX-2. After 12 weeks most of the cement had been resorbed in both groups. Both materials were considered to have a high biocompatibility since no marked immunological response was induced and extensive bone ingrowth was observed. The conclusion from the study was that pCPC with ZrO(2) radiopacifier is a promising alternative regarding bone replacement material and may be suggested for treatment of, for example, vertebral fractures based on its high biocompatibility, fast bone ingrowth, and good handling properties.     

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。     

自固化磷酸钙人工骨的最新研究进展

自固化磷酸钙（ＣＰＣ）是数年前在美国研制成功的一种非陶瓷型羟基磷灰石类（ＨＡＰ）代骨材料。它克服了陶瓷ＨＡＰ烧结形成、修整困难等缺点，具有制备容易、使用方便等优点。１９９１年以来，ＣＰＣ开始在临床试用，修复颅骨，获得满意效果。本文报告了ＣＰＣ的最新研究成果，包括固化过程及固化工艺的研究，快速凝固型、抗水型ＣＰＣ的研究，有机复合ＣＰＣ水门汀的研究和作为载体缓释多种药物的体外试验结果等。随着研究范围的