首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 125 毫秒
1.
目的比较钛合金(Ti-6Al-4V)和钴铬合金(Chromium-Cobalt alloy)表面白色念珠菌粘附能力的大小,研究表面粗糙度与细菌粘附的关系.方法将不同表面粗糙度的钛合金和钴铬合金试件进行白色念珠菌体外粘附试验,采用菌落形成计数法测定试件表面的细菌粘附量.结果各钛合金试件组的细菌粘附量均少于相同表面粗糙度的钴铬合金试件组,两种金属试件表面的细菌粘附量均随表面粗糙度的增大而增加.结论钛合金较钴铬合金更能减少由白色念珠菌引起的义齿性口炎等并发症,同时修复体表面严格的研磨抛光也能有效减少这些并发症.  相似文献   

2.
目的钛合金经酸碱两步预处理后在表面快速沉积羟基磷灰石涂层。方法钛合金(Ti_6Al_4V)均分为A、B两组。A组先用砂纸打磨,再用0.6mol/L NaOH在160℃下处理24h;B组先用H_2SO_4与HCl混合酸腐蚀1h,再用0.6mol/L NaOH在160℃处理24h。两组试件各8片分别置于过饱和钙磷溶液SCS1- SCS8中24h。XRD和SEM分析涂层成分、表面和断面形貌。表面形貌仪分析沉积前样品的表面粗糙度。结果在SCS1溶液中的钛合金片表面均沉积了致密的羟基磷灰石涂层,涂层表面由片状晶体组成,涂层厚度约为30μm。结论B组样品避免了对试样的打磨,在合适的SCS溶液中同样可以快速沉积羟基磷灰石涂层。该工艺特别适合在复杂形状的样品表面沉积涂层。  相似文献   

3.
人工关节改性材料的生物摩擦学研究   总被引:1,自引:0,他引:1       下载免费PDF全文
目的 研究不同人工关节材料的改性技术及生物摩擦学性能,为新型人工关节设计提供可靠的技术与理论基础。方法 选用表面渗碳、微弧氧化和氮离子注入技术对钛合金表面进行改性,以提高其耐磨损性能;超高分子量聚乙烯则采用填充改性技术,制备了UHMWPE/BHA、UHMWPE/NC和UHMWPE/VE复合材料,通过提高UHMWPE关节假体的承载能力和蠕变抗力,降低其磨损率;以聚乙烯醇(PVA)为基体材料,选用纳米羟基磷灰石(HA)为增强剂,制备了PVA/HA复合仿生人工软骨材料,考察了其摩擦学特性。结果 (1) 钛合金的表面改性可获得结合性能良好的表面陶瓷层,可有效提高钛合金的耐磨损性能。(2)超高分子量聚乙烯的填充改性,可获得耐磨损性能良好的关节复合材料,有效减少超高分子量聚乙烯磨损颗粒的产生并降低其磨损颗粒引起的生物学反应  相似文献   

4.
激光熔凝一步制备复合生物陶瓷涂层的 生物相容性   总被引:2,自引:0,他引:2  
在钛合金表面上预涂敷 Ca HPO4 - Ca CO3- Y2 O3混合粉末 ,进行激光同步合成和熔覆 ,获得了以 TC4为基材的生物陶瓷涂层复合材料。将该涂层材料植入成年狗的股骨中进行生物相容性试验研究。结果表明 ,该涂层材料对动物的组织和细胞无毒副作用 ,且涂层有良好的生物相容性 ,有诱导骨生长和不影响成骨细胞与破骨细胞活性的特性。  相似文献   

5.
对 DL C膜 / Ti6Al4V梯度材料和 Ti6Al4V钛合金进行了血液相容性稳定性研究。用数字图像分析方法分别测定了材料生物摩擦磨损实验前后的血小板消耗率。研究表明 ,在 Hank' s溶液润滑条件下 ,经过 2 0 0 0 m摩擦磨损实验后 ,Ti6Al4V钛合金血小板消耗率显著增加约 5 0 % ,而 DL C膜 / Ti6Al4V梯度材料血小板消耗率没有明显增加。说明 DL C膜 / Ti6Al4V梯度材料在使用条件下具有很好的血液相容性稳定性  相似文献   

6.
钛金属材料在医学领域应用广泛,新型低弹性模量的β型钛合金在保留传统钛合金材料固有优点的基础上,完全去除了细胞毒性元素,基本上相当于人骨组织的弹性模量.文章综述了各种钛材料表面形态对成纤维细胞生物学行为的影响,材料的表面形态是影响生物结合的因素之一,它与成纤维细胞之间存在着一种相互影响、相互促进的关系;不同钛合金表面形态对成纤维细胞的影响也不同,在一定范围内,成纤维细胞对钛合金的亲和性随其表面形态粗糙程度的增加而增加;通过对钛不同的表面改性,钛合金材料表现出对成纤维细胞生物学性状的影响也不同,这主要表现在对各种细胞因子和酶类的表达方面.并介绍低弹性模量钛合金表面规则微形态的作用,展望其临床应用前景.  相似文献   

7.
目的利用等离子体增强化学气相沉积(plasma enhanced chemical vapor deposition,PECVD)技术,在不同粗糙度医用钛合金表面制备类金刚石薄膜(diamond-like carbon film,DLC),并对类金刚石薄膜的膜-基结合力、电化学腐蚀行为及生物学行为进行研究,探索基底材料喷砂预处理对于表面制备的类金刚石薄膜是否是一种有效改性方法。方法通过不同粒度的Al2O3在一定条件下喷砂钛合金表面,制备出不同粗糙度表面的钛合金片,采用PECVD技术在其表面制备类金刚石薄膜。通过扫描电子显微镜、X-射线光电子能谱仪、拉曼光谱仪、接触角测量仪、表面性能测试仪和电化学方法检测各组样品的物理化学性能表征;利用MTT比色法、荧光染色法进行薄膜表面生物学行为的评价。结果将DLC沉积在喷砂预处理的钛合金表面,可以明显增强类金刚石的膜-基结合力,最高达到45N;耐腐蚀性研究中,表面沉积DLC的钛合金实验组腐蚀电位均正向大于未沉积DLC的钛合金组(P0.05);生物学行为研究中,在60#Al2O3喷砂处理钛合金表面沉积DLC的S60实验组细胞增殖状况最佳,明显大于未喷砂S0组(P0.05)。结论将钛合金基底喷砂预处理后沉积DLC,可以提高类金刚石薄膜的膜-基结合力、耐腐蚀性及生物相容性,是一种有效的医用钛合金表面改性方法,具有潜在的临床应用价值。  相似文献   

8.
钛及钛合金在口腔科应用的研究方向   总被引:53,自引:0,他引:53  
指出钛合金目前在口腔科应用过程中存在的问题及研究方向,着重介绍了新合金的研制,钛及钛及钛合金表面处理、口内腐蚀性以及钛及钛合金加工工艺等领域的研究重点和发展趋势。  相似文献   

9.
背景:人工关节从开始设计到临床应用已经经历了近一个世纪的历史,人工关节的先导为人工髋关节,随着在临床上的技术应用不断娴熟,推动了腕关节、肩关节、膝关节等人工关节的设计、应用及改进。目的:总结运动性关节损伤中人工关节材料的应用进展及性能特征。方法:由第一作者检索1980至2015年Pub Med数据库(http://www.ncbi.nlm.nih.gov/PubM ed)、万方数据库(http://wanfangdata.com.cn/)及CNKI中国期刊全文数据库(http://www.cnki.net/),以"sports;cartilage injury;Artificial Joint"为英文检索词,"运动,关节软骨损伤,人工关节"为中文检索词,对目前国内外人工关节的研究资料进行了分析和归纳,逐一介绍并分析了国内外常用的人工关节材料,并从材料科学的角度分析了各种材料在应用时的优劣,对目前常用人工关节的表面处理方法作了阐述,并从发展的角度指出了人工关节的研究方向。结果与结论:钛合金的表面改性可获得结合性能良好的表面陶瓷层,可有效提高钛合金的耐磨损性能。超高分子量聚乙烯的填充改性,可获得耐磨损性能良好的关节复合材料,有效减少超高分子量聚乙烯磨损颗粒的产生并降低其磨损颗粒引起的生物学反应。陶瓷人工关节的进一步研究与完善将是未来人工关节的发展方向。  相似文献   

10.
采用氢氧化钠和硝酸锶混合溶液对Ti6Al4V合金进行水热处理,温度180℃,时间1、3和6 h。X射线衍射、扫描电镜、电子能谱和X射线光电子能谱分析表明,水热处理后钛合金表面形成了钛酸锶的纳米颗粒薄膜,颗粒尺寸80~230 nm,薄膜中含有极少量铝和钒元素。在无钙Hank’s平衡盐液中的动电位极化和电化学阻抗实验表明,与抛光试样相比,水热处理3h试样的耐蚀性大幅提高。显微硬度压入实验表明,钛酸锶薄膜具有良好的附着性和内聚力。水热处理制备钛酸锶薄膜的方法可用于钛合金Ti6Al4V骨科植入体的表面改性。  相似文献   

11.
The osseo-integration, corrosion resistance, and tribological properties of the commonly used bioimplant alloy Ti–6Al–4V were enhanced using a laser-based surface nitridation process. The biomedical properties of the laser nitrided Ti–6Al–4V were investigated using experimental and computational methodologies. Electrochemical analysis of laser nitrided titanium in simulated body fluid (SBF) was performed to assess the biomedical characteristics in near-human body conditions. Additionally, the corrosive wear performance of these laser nitrided samples was evaluated using pin-on-disk geometry with a zirconia pin counter surface in SBF to mimic the biological scenario. Osteoblast studies were conducted to evaluate cell affinity towards titanium nitrided bioimplant material. Cells adhered to all substrates, with high viability. Initial cell adhesion was revealed by focal adhesion formation on all substrates. Cells can proliferate on samples treated with 1.89 and 2.12 × 106 J/m2 laser conditions, while those treated with 1.70 × 106 J/m2 inhibited proliferation. Thus, microstructural and phase observations, electrochemical analyses, corrosive wear evaluation, and cell behavior analysis of laser nitrided surface of bioimplant material (Ti–6Al–4V) indicated that laser nitriding greatly improves the performance of bioimplant material.  相似文献   

12.
The objective of this investigation was to study the influence of water exposure on the three-body wear of composite restoratives. A three-body wear instrumentation was used to investigate the wear resistance of five composite restoratives [Silux Plus (SX), Z100 (ZO), Ariston pHc (AR), Surefil (SF) and Tetric Ceram (TC)] with and without exposure to water. An amalgam alloy [Dispersalloy (DA)] was used as control. Ten specimens were made for each material. The specimens were conditioned in artificial saliva at 37 degrees C for 24 h and randomly divided into two groups of 5. The first group was subjected to wear testing immediately after the 24 h conditioning period, while the second group was conditioned in distilled water at 37 degrees C for 7 days prior to wear testing. All materials were wear tested at 15 N contact force against SS304 counter-bodies for 20,000 cycles with millet seed slurry as third-body. Wear depth (microm) was measured using profilometry, and results were analyzed by ANOVA/Scheffe's and independent sample t-tests at significance level 0.05. Ranking of wear resistance was as follows: without water exposure: DA > ZO > SF > AR > SX > TC; with water exposure: DA > ZO > SX > SF > AR > TC. Wear factor ranged from 2.20 for ZO to 7.13 for TC without water exposure and from 46.00 for ZO to 143.00 for TC with exposure to water. Exposure to water significantly increased three-body wear for all composite restoratives, but did not affect wear of the amalgam alloy. The effects of water exposure must be considered for the evaluation of wear in all polymeric composite restoratives.  相似文献   

13.
A 12-channel wear screening device was used to compare the wear properties of a variety of prosthetic joint materials. Two types of tests were run: (1) Ultrahigh molecular weight (UHMW) polyethylene bearing against metal or ceramic counterfaces and (2) various polymers bearing against 316 stainless steel as a standard counterface. Wear was quantified by weighing the polymer specimens, with presoaking and control-soak specimens used to minimize the error due to fluid absorption. The specimens were lubricated with bovine blood serum. Friction and polyethylene wear was very low with each of the metals (316 stainless steel, cobalt-chrome alloy, multiphase alloy, and titanium 6-4 alloy) such that the differences in wear rate would not be significant in terms of choosing a material for clinical application. However, titanium 6-4 alloy was found to be especially susceptible to abrasive wear by particles of acrylic cement. Nitrided titanium 6-4 counterfaces were impervious to acrylic abrasion. Polyethylene wear against highly polished, fully dense ceramics (Sialon, Alumina, Macor, and pyrolytic graphite) was as low as that with the metal counterfaces. Wear increased slightly with increasing ceramic surface roughness. The coefficient of friction of polyethylene against pyrolytic graphite was two to three times higher than with the metals or other ceramics. All of the alternate polymers underwent more wear than UHMW polyethylene. Teflon and polyester, two polymers that have proven unsuccessful in prior clinical use, had wear rates 1,600 and 830 times greater than polyethylene, respectively, an indication that the laboratory wear test provided a quantitative prediction of the behavior of the materials in vivo. However, it was difficult to assess the clinical significance of the less extreme wear rates since the ability of the tissues encapsulating a prosthesis to accomodate wear debris is not known on a quantitative basis.  相似文献   

14.
Osteolysis caused by wear particles from polyethylene in artificial hip joints is of great concern. Various bearing couple combinations, bearing material improvements, and surface modifications have been attempted to reduce such wear particles. With the aim of reducing the wear and developing a novel artificial hip-joint system, we created a highly lubricious metal-bearing material: A 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer was grafted onto the surface of the cobalt-chromium-molybdenum (Co-Cr-Mo) alloy. For ensuring the long-term retention of poly(MPC) on the Co-Cr-Mo alloy, we used a 4-methacryloxyethyl trimellitate anhydride (4-META) intermediate layer and photo-induced graft polymerization technique to create a strong bonding between the Co-Cr-Mo substrate and the poly(MPC) chain via the 4-META layer. The Co-Cr-Mo alloy was pretreated with nitric acid and O(2) plasma to facilitate efficient interaction between the 4-META carboxyl group and the surface hydroxyl group on the Cr oxide passive layer of the Co-Cr-Mo alloy. After MPC grafting, the MPC unit peaks were clearly observed in the Fourier-transform infrared spectroscopy with attenuated total reflection (FT-IR/ATR) and X-ray photoelectron spectroscopy (XPS) spectra of the Co-Cr-Mo surface. Tribological studies with a pin-on-plate machine revealed that surface MPC grafting markedly lowered the friction coefficient. We concluded that the grafted poly(MPC) layer successfully provided high lubricity to the Co-Cr-Mo surface.  相似文献   

15.
Wear resistance of experimental Ti-Cu alloys   总被引:6,自引:0,他引:6  
After using cast titanium prostheses in clinical dental practice, severe wear of titanium teeth has been observed. This in vitro study evaluated the wear behavior of teeth made with several cast titanium alloys containing copper (CP Ti+3.0 wt% Cu; CP Ti+5.0 wt% Cu; Ti-6Al-4V +1.0 wt% Cu; Ti-6Al-4V+4.0 wt% Cu) and compared the results with those for commercially pure (CP) titanium, Ti-6Al-4V, and gold alloy. Wear testing was performed by repeatedly grinding upper and lower teeth under flowing water in an experimental testing apparatus. Wear resistance was assessed as volume loss (mm(3)) at 5kgf (grinding force) after 50,000 strokes. Greater wear was found for the six types of titanium than for the gold alloy. The wear resistance of the experimental CP Ti+Cu and Ti-6Al-4V+Cu alloys was better than that of CP titanium and Ti-6Al-4V, respectively. Although the gold alloy had the best wear property, the 4% Cu in Ti-6Al-4V alloy exhibited the best results among the titanium metals. Alloying with copper, which introduced the alpha Ti/Ti(2)Cu eutectoid, seemed to improve the wear resistance.  相似文献   

16.
Knee and hip joint replacement implants involve a sliding contact between the femoral component and the tibial or acetabular component immersed in body fluids, thus making the metallic parts susceptible to tribocorrosion. Micro-motions occur at points of fixation leading to debris and ion release by fretting corrosion. β-Titanium alloys are potential biomaterials for joint prostheses due to their biocompatibility and compatibility with the mechanical properties of bone. The biotribocorrosion behavior of Ti-29Nb-13Ta-4.6Zr was studied in Hank's balanced salt solution at open circuit potential and at an applied potential in the passive region. Reciprocating sliding tribocorrosion tests were carried out against technical grade ultra high molecular weight polyethylene, while fretting corrosion tests were carried out against alumina. The wear of the alloy is insignificant when sliding against polyethylene. However, depassivation does take place, but the tested alloy showed an ability to recover its passive state during sliding. The abrasivity of the alloy depends on the electrochemical conditions of the contact, while the wear of polyethylene proceeds through third body formation and material transfer. Under fretting corrosion conditions recovery of the passive state was also achieved. In a fretting contact wear of the alloy proceeds through plastic deformation of the bulk material and wear resistance depends on the electrochemical conditions.  相似文献   

17.
Starosvetsky D  Gotman I 《Biomaterials》2001,22(13):1853-1859
Nickel-titanium (NiTi, nitinol) shape memory alloy was nitrided using an original powder immersion reaction assisted coating (PIRAC) method in order to modify its surface properties. PIRAC nitriding method is based on annealing the samples in the atmosphere of highly reactive nitrogen supplied by decomposition of unstable nitride powders or, alternatively, by selective diffusion of the atmospheric nitrogen to the sample surface. Being a non-line-of-sight process, PIRAC nitriding allows uniform treatment of complex shape surgical implants. Hard two-layer titanium nitride (TiN)/Ti2, Ni coatings were obtained on NiTi surface after PIRAC anneals at 900 and 1000 degrees C. PIRAC coating procedure was found to considerably improve the corrosion behavior of NiTi alloy in Ringer's solution. In contrast to untreated nitinol, no pitting was observed in the samples PIRAC nitrided at 1000 degrees C, 1 h up to 1.1 V. The coated samples were also characterized by very low anodic currents in the passive region and by an exceedingly low metal ion release rate. The research results suggest that PIRAC nitriding procedure could improve the in vivo performance of NiTi alloys implanted into the human body.  相似文献   

18.
Improved methods to increase surface hardness of metallic biomedical implants are being developed in an effort to minimize the formation of wear debris particles that cause local pain and inflammation. However, for many implant surface treatments, there is a risk of film delamination due to the mismatch of mechanical properties between the hard surface and the softer underlying metal. In this article, we describe the surface modification of titanium alloy (Ti-6Al-4V), using microwave plasma chemical vapor deposition to induce titanium nitride formation by nitrogen diffusion. The result is a gradual transition from a titanium nitride surface to the bulk titanium alloy, without a sharp interface that could otherwise lead to delamination. We demonstrate that vitronectin adsorption, as well as the adhesion and spreading of human mesenchymal stem cells to plasma-nitrided titanium is equivalent to that of Ti-6Al-4V, while hardness is improved 3- to 4-fold. These in vitro results suggest that the plasma nitriding technique has the potential to reduce wear, and the resulting debris particle release, of biomedical implants without compromising osseointegration; thus, minimizing the possibility of implant loosening over time.  相似文献   

19.
The corrosion and tribocorrosion behavior of an as-cast high carbon CoCrMo alloy immersed in phosphate buffered solution (PBS) and phosphate buffered solution with bovine serum albumin (PBS+BSA) have been analyzed by electrochemical techniques and surface microscopy. After the electrochemical characterization of the alloy in both solutions, the sample was studied tribo-electrochemically (by open circuit potential, OCP measurements, potentiodynamic curves and potentiostatic tests) in a ball-on-disk tribometer rotating in different sliding velocities. The influence of solution chemistry, sliding velocity and applied potential on the corrosion and tribocorrosion behavior of the CoCrMo alloy has been studied. Anodic current density increases with sliding velocity but wear rate does not change at an applied anodic potential; on the other hand, BSA modifies the wear debris behavior (by agglomerating the debris formed by mechanical removal of particles) thus increasing the mechanical wear volume. Under cathodic conditions, cathodic current density also increases during mechanical contact while the wear rate decreases with sliding velocity and BSA lubricates the contact thus reducing the total wear volume with respect to the non-containing BSA solution. The work shows how the electrode potential critically affects the corrosion and tribocorrosion rates by increasing the wear coefficients at applied anodic potentials due to severe wear accelerated corrosion.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号