生物活性陶瓷/聚合物复合材料的研究进展

1 引言 生物医用复合材料(biomedical composite materials)是由两种或两种以上的不同材料复合而成的生物医用材料,主要用于人体组织的修复、替换和人工器官的制造。自从有研究发现人骨组织中含有58％的钙、磷成分,许多研究者就把钙磷陶瓷作为一种潜在的移植物。早期应用较多的生物陶瓷主要是一些惰性材料,如     

羟基磷灰石复合骨组织工程支架的研究进展

近年来,以生物活性陶瓷、聚合物等材料为基础复合而成的人工骨骼材料得到了广泛的研究并取得了巨大的进展。纳米羟基磷灰石(nano Hydroxyapatite,n HA)因其具有良好的生物相容性和生物活性,被大量应用于骨组织的移植与修复,但由于现有工艺制备的磷灰石本身力学性能不够完美,进而限制了其应用的广泛性,因此,制备综合性能优越的纳米羟基磷灰石/聚合物复合生物材料是当今骨组织工程中研究的热点。在此,就纳米羟基磷灰石与壳聚糖、胶原、聚乳酸等高分子材料复合而成的新型骨移植替代材料的合成方法、力学性能和生物相容性进行简单的介绍。     

骨科纳米生物材料的研究现状与展望

背景：随着纳米技术不断发展,越来越多的纳米技术已被应用到生物医药领域,为疾病诊断及治疗提供了很大的利益。 目的：综述纳米生物材料的研究现状及其在生物医学上的应用。 方法：由第一作者应用计算机检索中国期刊全文数据库、PubMed数据及万方数据库,2000年1月至2014年10月关于纳米生物材料、纳米生物陶瓷材料的文章,设定中文检索词为“纳米、生物陶瓷”,英文检索词为“nano, bioceramic”。 结果与结论：随着纳米技术的不断研究及开发,一些纳米技术已进入了实际应用阶段,应用纳米技术能够对疾病的发生、发展起防治作用。纳米陶瓷显著提高了材料的强度、韧性和超塑性,克服了生物陶瓷的许多不足,在骨科领域获得重要应用,比如有人工关节、人工骨骼、骨充填材料、骨置换材料、人工椎体等。 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     

硬组织替换用羟基磷灰石复合材料的研究进展

羟基磷灰(HA)石具有与人骨无机质相似的化学成分和晶体结构，被认为是一种很有潜力的人体硬组织替换材料，但脆性太大限制了其在承载部位骨替换中的应用。因而各种羟基磷灰石复合材料受到了极大的关注。本文按照增强体的种类对羟基磷灰石复合材料进行了分类介绍。生物活性陶瓷、生物活性玻璃及玻璃陶瓷、生物惰性陶瓷、聚合物及金属等都被用来制备羟基磷灰石复合材料，但仍没有一种材料能够很好的满足硬组织替换的需要。现有HA复合材料存在的关键问题是生物性能与力学性能之间不能很好地匹配。     

骨修复材料的研究进展

由于自体骨和异体骨移植治疗骨缺损存在许多不可避免的问题 ,所以 ,人们开始研制人工骨修复材料。本文综述了生物陶瓷、胶原、脱钙骨、合成聚合物等骨修复材料的研究和应用现状。作者认为 ,将几类生物材料复合加工 ,研制出类似于人体骨组织的材料 ,将是今后骨修复材料的发展趋势     

骨修复材料的研究进展

由于自体骨和异体骨移植治疗骨缺损存在许多不可避免的问题,所以,人们开始研制人工骨修复材料。本文综述了生物陶瓷、胶原、脱钙骨、合成聚合物等骨修复材料的研究和应用现状。作者认为,将几类生物材料复合加工,研制出类似于人体骨组织的材料,将是今后骨修复瓣发展趋。     

不同生物支架材料修复骨缺损的性能与评价

目的:评价不同生物材料修复骨缺损的性能与效果,寻找适合生物材料以利于临床应用。方法:以"生物材料,骨缺损,骨髓基质干细胞,细胞因子,组织工程"为中文关键词,以"biological materials,bone defect,bone marrowstroma lcells,Cytokine,tissue engineering"为英文关键词,采用计算机检索1995-01/2010-01相关文章。纳入与有关生物材料与组织工程骨缺损修复相关的文章;排除重复研究或Meta分析类文章。以22篇文献为主重点讨论了骨缺损修复生物材料及其性能。结果:目前骨组织工程支架材料主要有两类:一类是天然生物衍生材料,由天然生物组织经一系列理化方法处理而得,如胶原、珊瑚、生物衍生骨等。另一类是人工合成材料,主要为生物陶瓷和高分子材料,如钙磷陶瓷、自固化磷酸钙、聚乳酸、聚乙内酯,聚乙烯乙二醇等。目前,单一的材料,无论是生物陶瓷还是高分子(天然或人工合成),都不能满足骨组织修复的要求,因而复合支架材料的研究备受瞩目。如纳米羟基磷灰石与胶原、羟基磷灰石与磷酸三钙、羟基磷灰石与聚乳酸-聚羟乙酸复合等。结论:复合支架材料能保证足够的强度而且能有效结合种子细胞和生长因子,有利于组织工程骨的构建。     

《中国组织工程研究》杂志关注组织工程研究中的生物材料

1期刊关注来自组织工程研究中的多种生物材料:组织工程骨材料,组织工程软骨材料,组织工程血管材料,组织工程神经材料,药物控释材料,纳米生物材料,膜生物材料,复合支架材料,可降解吸收材料,细胞外基质材料,抗菌抗病毒材料……2期刊关注组织工程研究中更多生物材料的最新研究进展:再生医学材料,心血管材料,骨修复材料,医用金属材料,纳米生物材料,生物材料先进制造,神经修复材料,生物陶瓷材料,材料生物学评价,生物复合材料,海洋生物材料,生物医用高分子材料,材料生物力学评价,影像材料与技术,颅颌面整形外科材料,智能仿生材料,材料表界面工程,材料力学及表面改性,生物材料模型构建……     

纳米羟基磷灰石骨修复复合材料的研究进展

羟基磷灰石（Hydroxyapatite，HA）是一种性能良好的骨修复材料，但是由于脆性而限制了它在承力部位的应用。天然骨本身是纳米羟基磷灰石（Nanohydroxyapatite，n．HA）和胶原的复合材料，从仿生的角度看，n—HA与其它材料复合可以提高生物相容性和力学性能。目前研究的纳米羟基磷灰石复合材料可分为两类：非降解的纳米羟基磷灰石复合材料和可降解的纳米羟基磷灰石复合材料。前者包括n—HA/聚乙烯、n-HA／尼龙以及n—HA／聚丙烯酸。后者主要有n—HA与胶原、明胶、壳聚糖、聚乳酸和聚酸酐等的复合材料。本文详细综述了近年来纳米羟基磷灰石复合材料的制备、力学性能以及生物学性能的研究进展。     

人工膝关节常用假体材料及其生物相容性

背景：理想的假体材料对人工膝关节的功能、预后至关重要。 目的：评价各种人工膝关节生物材料的性能、应用及其生物相容性,寻找合理的膝关节替代物。 方法：采用电子检索的方式,在万方数据库(http://www.wanfangdata.com.cn/)中检索1999-01/2009-12有关生物材料应用于人工膝关节的研究文章,关键词为“组织工程,人工膝关节,生物材料”。排除重复研究、普通综述或Meta分析类文章,筛选纳入17篇文献进行评价。 结果与结论：传统的金属和骨水泥材料仍广泛运用于人工膝关节假体中,随着医学和组织工程技术的发展,各种合成生物材料相继出现。近来出现了生物相容性较好的生物陶瓷及高分子复合材料,但存在易磨损的缺点,改进上述材料的缺点,寻求理想的人工膝关节假体材料是当前生物医学工程研究的热点之一。虽然传统的金属、骨水泥、生物陶瓷及高分子复合材料均在临床上大量应用于人工膝关节,但由于其存在各自不可避免的缺点,理想的人工膝关节假体材料仍需进一步开发。     

Current progress in inorganic artificial biomaterials

In this review, recent advances in bioceramics, metallic biomaterials, and their composites are discussed in terms of their material properties and new medical applications. Porous calcium phosphate ceramics have attracted a lot attention as scaffolds for tissue-engineering purposes since the porous structure allows bone ingrowth. The addition of biodegradable polymers like chitosan, gelatin, and collagen have modified the degradability of the ceramics and their mechanical properties. Titanium (Ti) alloys are being developed for the fabrication of medical devices for the replacement of hard tissue such as artificial hip joints, bone plates, and dental implants because they are very reliable from the viewpoint of mechanical performance. Physical treatment such as grooving or setting a spatial gap on the surface of materials is applicable to improve the apatite formation on the Ti alloys. Blood-compatible polymers such as poly(ethylene glycol) have been successfully fixed on the surface of Ti via chemical bonding by an electrodeposition method. New functions have been explored in Ni-free, Co–Cr–Mo alloys and Mg alloys. In addition, yttrium-containing or phosphorus-containing glass microspheres (20–30 μm in diameter) and ferrimagnetic ceramic particles have exhibited great potential to realize minimally invasive treatment of cancer without surgical operation via in situ radiotherapy or hyperthermia of cancer, but it is still a major challenge to clarify the biological reaction between the artificial implants and living body before their application.     

Processing, properties, and in vitro bioactivity of polysulfone-bioactive glass composites

The mismatch between the mechanical properties of bioceramics and natural tissue has restricted in several cases a wider application of ceramics in medical and dental fields. To overcome this problem, polymer matrix composites can be designed to combine bioactive properties of some bioceramics with the superior mechanical properties of some engineering plastics. In this work, polymer particulate composites composed of a high mechanical-property polymer and bioactive glass particles were produced and both the in vitro bioactivity and properties of the system were investigated. Composites with different volume fraction and particle size were prepared. In vitro tests showed that hydroxy-carbonate-apatite can be deposited on the surface of a composite as early as 20 h in a simulated body fluid. Ionic evolution from a composite with 40% volume fraction of particles was demonstrated to be similar to bulk bioactive glasses. The mechanical properties of some of the obtained composites had values comparable with the ones reported for bone. Moreover, a physical model based on dynamical mechanical tests showed evidences that the interface of the composite was aiding in the stress transfer process.     

Production and evaluation of biodegradable composites based on PHB-PHV copolymer

In recent years, emphasis in biomaterials engineering has moved from materials that remain stable in the biological environment to materials that can degrade in the human body. Biodegradable materials are designed to degrade gradually and be replaced eventually by newly formed tissue in the body. In this investigation, two particulate bioactive ceramics, i.e., hydroxyapatite (HA) and tricalcium phosphate (TCP), were incorporated into polyhydroxybutyrate-polyhydroxyvalerate (PHB-PHV), which is a biodegradable copolymer. to produce new biomaterials for potential medical applications. All raw materials were commercially available and they were characterised prior to composite production. HA/PHB-PHV and TCP/PHB-PHV composites containiing up to 30 vol% of the bioceramics were produced through an established procedure. Compounded and compression moulded materials were evaluated using various techniques including thermogravimatric analysis, scanning electron microscopy, differential scanning calorimetry and dynamic mechanical analysis. The results showed that intended compositions of composites had been achieved and bioceramic particles were well distributed in the polymer. The degradation temperature of PHB-PHV was significantly reduced by the incorporation of bioceramics, while the melting temperature was slightly affected by the addition of bioceramics. The crystallinity of PHB-PHV was also varied with the presence of HA or TCP particles. The storage modulus and loss modulus of the composites increased with the increase in HA or TCP content. Composites containing the highest percentage of bioceramics exhibited the highest stiffness. Preliminary in vitro study indicated enhanced ability of the composites to induce the formation of bone-like apatite on their surfaces.     

Macroporous bioceramics: a remarkable material for bone regeneration

This review summarises the major developments of macroporous bioceramics used mainly for repairing bone defects. Porous bioceramics have been receiving attention ever since their larger surface area was reported to be beneficial for the formation of more rigid bonds with host tissues. The study of porous bioceramics is important to overcome the less favourable bonds formed between dense bioceramics and host tissues, especially in healing bone defects. Macroporous bioceramics, which have been studied extensively, include hydroxyapatite, tricalcium phosphate, alumina, and zirconia. The pore size and interconnections both have significant effects on the growth rate of bone tissues. The optimum pore size of hydroxyapatite scaffolds for bone growth was found to be 300?μm. The existence of interconnections between pores is critical during the initial stage of tissue ingrowth on porous hydroxyapatite scaffolds. Furthermore, pore formation on β-tricalcium phosphate scaffolds also allowed the impregnation of growth factors and cells to improve bone tissues growth significantly. The formation of vascularised tissues was observed on macroporous alumina but did not take place in the case of dense alumina due to its bioinert nature. A macroporous alumina coating on scaffolds was able to improve the overall mechanical properties, and it enabled the impregnation of bioactive materials that could increase the bone growth rate. Despite the bioinertness of zirconia, porous zirconia was useful in designing scaffolds with superior mechanical properties after being coated with bioactive materials. The pores in zirconia were believed to improve the bone growth on the coated system. In summary, although the formation of pores in bioceramics may adversely affect mechanical properties, the advantages provided by the pores are crucial in repairing bone defects.     

Bioinspired structure of bioceramics for bone regeneration in load-bearing sites

The major problem with the use of porous bioceramics as bone regeneration grafts is their weak mechanical strength, which has not been overcome to date. Here we described a novel way to solve this problem. Beta-tricalcium phosphate (β-TCP) bioceramics with a bioinspired structure were designed and prepared with a porous cancellous core (porosity: 70–90%) inside and a dense compact shell (porosity: 5–10%) outside that mimics the characteristics of natural bone. They showed excellent mechanical properties, with a compressive strength of 10–80 MPa and an elastic modulus of 180 MPa–1.0 GPa, which could be tailored by the dense/porous cross-sectional area ratio obeying the rule of exponential growth. The in vitro degradation of the bioinspired bioceramics was faster than that of dense bioceramics but slower than that of porous counterparts. The changes in mechanical properties of the bioinspired ceramics during in vitro degradation were also investigated. A concept of the bioinspired macrostructure design of natural bone was proposed which provided a simple but effective way to increase the mechanical properties of porous bioceramics for load-bearing bone regeneration applications. It should be readily applicable to other porous materials.     

可注射型组织工程骨支架材料的研究进展

可注射型组织工程骨支架材料是一种具有一定形态和机械强度的支架材料,可与种子细胞复合,以流体的形式注射到骨组织缺损部位,最终形成新骨,达到结构恢复和功能重建的目的.此材料具有创伤小、可塑性好的特点,可以修复形态不规则的骨缺损,能够很好地复合生长因子,是目前较为理想的骨组织缺损的修复方式.在众多可注射骨组织工程材料中,生物陶瓷材料、高分子材料等被证明有高度的生物相容性和良好的机械性能,已成为骨组织工程材料方面的研究重点.旨在对生物陶瓷材料、高分子材料、生物陶瓷与高分子复合材料的发展与应用作一综述.     

Artificial organs: recent progress in metals and ceramics

The superior properties and novel functions of biomaterials, including metals and ceramics commonly used as implants and medical devices, have been the focus of a number of recent papers. New functions have been explored in metastable β-Ti alloys, Ni-free Co–Cr–Mo alloys, Mg alloys, and other materials. In addition, porous metals and ceramics with sophisticated structures have been studied as scaffolds for regenerative medicine. In this review, recent advances in bioceramics, metallic biomaterials, and their composites are discussed in terms of their material properties and morphology.     

基于聚己内酯纤维的组织工程支架研究进展

聚己内酯(PCL)是一种生物相容性好、可吸收、易加工改性的聚酯,材料基于PCL纤维的组织工程支架,具有比表面积高、机械性能良好与孔径、孔隙率和纤维取向等结构特征易调控等特点,被广泛应用于组织工程领域。重点综述PCL纤维的组织工程支架的主要应用缺陷(包括细胞亲和力差、降解速度过慢及机械强度低)及改进手段,同时针对基于PCL纤维的组织工程支架在皮肤、血管、神经、肌腱、韧带和软骨等组织再生的最新进展进行归纳总结,发现目前多数研究集中于通过引入生物活性物质或药物以改善细胞-支架相互作用和调控支架降解行为,或通过选取不同的纺丝工艺和参数以改变支架的物理结构,调控支架机械性能与细胞诱导行为。此外,目前多数研究仍停留在实验室阶段,利用基于PCL纤维的组织工程支架低成本、易加工的优势以加快其临床转化是未来重要的发展方向。     

Alloplastic materials for heart-valve prostheses

Alloplastic materials have found wide application in heart-valve prostheses, in spite of the need for permanent anticoagulant treatment. Though biological valves exhibit excellent thromboresistance, they fail in long-term application because of a disintegration of the tissue structure. An improvement of the blood compatibility of implantable material has been achieved on the basis of an identification of interfacial reactions between clotting plasma proteins and the solid surface. Rutile ceramics offer advantageous properties because: (i) surface induced activation processes are diminished and (ii) the chemical and mechanical resistance shows long-term stability. Rutile ceramics are utilised for a central-flow heart-valve prosthesis which is being subjected to accelerated fatigue studies.