钛表面处理方法对钛-瓷界面结合力和瓷表面色泽的影响

纯钛化学性质活泼,常温下其表面易形成一层氧化膜,高温下钛铸件表面易形成较厚的污染层,从而影响与瓷的结合,因此钛的表面处理至关重要。对钛表面的不同处理方法以及钛瓷结合力及钛瓷修复体颜色的影响作一综述。     

不同包埋材料与铸钛过程中表面反应层的变化

背景：目前为止,对于氧化镁系和氧化锆系包埋料应用于纯钛铸造工艺中的对比研究还没有详细的报道,而磷酸盐系包埋料对铸件表面反应层分层明显可作为对照。 目的：分析不同包埋料对铸钛表面反应层的影响。 方法：分别用磷酸盐系、氧化锆系、氧化镁系包埋材料包埋并铸造规格为10 mm×10 mm×1 mm的纯钛铸件,用扫描电镜、能谱分析、X射线衍射、显微硬度和金相观察的方法对铸件表面的反应层进行检测。 结果与结论：用磷酸盐系、氧化锆系、氧化镁系包埋料铸出的铸件在金相照片中观察表面反应层的厚度分别是70,45,12 μm。3种铸件分别在距反应层最表面100,60,40 μm处硬度值明显减少,由此处向钛基体内部硬度值变化较平稳;反应层中主要元素Al、Si、O 的含量随着深度增加逐渐减少。与氧化锆系包埋料和磷酸盐系包埋料相比,氧化镁系包埋料与钛铸件的反应较轻微,反应层较少,对纯钛铸造过程中产生的污染少,说明氧化镁系包埋料是铸造纯钛工艺中最理想的包埋料。     

纳米结构钛的生物力学性能研究

目的为改善植入材料生物力学相容性,探讨表面机械研磨处理(Surface mechanical Attrition Treatment,SMAT)对纯钛的力学性能影响。方法将厚度为1mm的纯钛板进行两面SMAT处理,之后进行力学性能测试,分析SMAT对纯钛力学性能的影响。结果SMAT处理后纯钛板表面形成了纳米晶,而整体成为了梯度材料。结果表明SMAT能使纯钛的强度提高、塑性下降、表面显微硬度大大提高。最重要的是,这种方法使钛的弹性模量显著降低,从而改善了钛的生物力学相容性。结论SMAT处理能使纯钛表面纳米化,并且使其弹性模量降低,能够改善它的生物力学相容性,在医用领域有良好前景。     

预氧化对钛与瓷结合的影响

本研究探讨了预氧化处理对低温瓷与纯钛及钛铝钒合金结合的影响，通过扫描同镜对界面的观察和剪切试验揭示预氧化处理显著削弱了瓷与钛材的结合强度，提示在钛材表面烤牙科瓷前不需作预氧化处理。     

占空比对微弧氧化纯钛膜层结构的影响*

背景：利用微弧氧化生成的纯钛表面陶瓷层特性与电化学参数有着较为密切的关系,目前尚且没有较为统一的标准参数。 目的：观察在不同占空比处理条件下,利用微弧氧化技术在纯钛表面形成含钙磷氧化层的结构特性。 方法：根据占空比的不同(5%,25%,45%,65%),采用微弧氧化技术处理纯钛试件,使用扫描电镜观察表面形貌,X射线能谱仪分析膜层表面元素,X射线衍射仪分析膜层物相。 结果与结论：微弧氧化处理后,纯钛表面形成了均匀多孔的陶瓷层,随着占空比增加,表面膜层变得粗糙不平,微孔直径增加,孔洞分布的不均匀性增加。膜层主要元素为Ti、P、O、Ca 4种,且Ca/P随着占空比的增加而增加,当占空比增大到45%时,Ca/P增加变得不明显。膜层表面有金红石型和锐钛矿型TiO2存在。提示占空比增加,微弧氧化膜层微孔直径增加,钙磷元素相对含量增加,锐钛矿型TiO2向金红石型发生转变。 关键词：微弧氧化;占空比;钛;膜层结构;晶相;元素 doi:10.3969/j.issn.1673-8225.2012.12.026     

硅烷偶联剂对纯钛表面改性及细胞相容性的影响

背景：目前国内将硅烷偶联用于金属表面预处理的报道较少。 目的：对NaOH碱处理的钛片行硅烷化改性,观察硅烷膜的表面形貌与结构特征及细胞相容性。 方法：对制得的纯钛试件行NaOH碱处理,然后分别以8%,15%,33%浓度的KH-550硅烷偶联剂进行改性处理,以纯钛片和碱处理的钛片为对照组,采用扫描电镜观察改性处理钛片表面微观形貌,采用能谱仪分析改性处理钛片表面的成分。将纯钛片、碱处理的钛片及不同浓度KH-550硅烷偶联剂改性处理的钛片分别与犬骨髓间充质干细胞共培养,观察材料表面细胞的形态及黏附。 结果与结论：硅烷膜由许多呈脑浆状的小片构成,排列紧密,主要由C、N、O、Si等元素组成。当硅烷溶液浓度为8%时,钛表面难以形成较完整的硅烷膜;当硅烷溶液浓度为15%时,钛表面形成的硅烷膜表面较8%浓度组钛表面相对较完整,但可仍见有较多裂纹,难以形成致密的硅烷膜;当硅烷溶液浓度为33%时,纯钛表面能形成致密的硅烷膜。犬骨髓间充质干细胞在33%浓度硅烷膜处理后钛基体上的黏附情况明显优于纯钛、碱处理钛片及8%,15%浓度硅烷膜处理后的钛片。说明33%硅烷化改性纯钛表面硅烷膜较完整,并且具有良好的生物相容性,可促进骨髓间质干细胞在活性层表面的黏附。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：     

用于人体关节植入物的多孔纯钛/钛合金研究

目的研究Ti6Al4V合金基体上经钎焊制得的多孔纯钛／钛合金,并对其各项性能进行表征,探讨其是否适用于人体关节植入物。方法制备钎焊多孔纯钛／钛合金表面多孔层,采用SEM观察其形貌及孔径,采用重量法计算其孔隙率,采用Instron 4057材料试验机进行结合强度测试,并根据国家标准GB／T16886-3完成遗传毒性实验。结果纯钛／钛合金多孔层孔径为100μm以上,孔隙率6％以上;多孔层与基体的结合强度达到27MPa。遗传毒性试验结果为阴性。结论经钎焊可制得纯钛／钛合金球形粉末多孔层,其孔隙率和孔径允许骨细胞长入;多孔层与基体的结合强度能够满足植入要求,并具有较好生物相容性;经钎焊制得的纯钛／钛合金多孔层是一种可用于人体关节植入物的表面结构形式。     

阳极氧化活化处理纯钛经皮种植体的体内外实验研究

为解决经皮器械在负重条件下的长期稳定和经皮密封问题，本文对比研究了阳极氧化表面以及光滑表面的纯钛种植体经皮植入动物体内的情况．并同时将人皮肤表皮细胞接种于这两种表面上进行培养，初步探讨了阳极氧化活化处理后的纯钛金属作为经皮植入体的可能性。结果表明：经皮部分钛金属的光滑表面与阳极氧化的微观粗糙表面对于术后炎性反应的影响无明显差异，阳极氧化活化表面不仅能与骨形成牢固结合，而且也可以与皮下组织紧密贴附。同时，在体内种植体表面形成的钙磷层可能也是形成经皮密封的原因之一，阳极氧化活化钛的微孔粗糙表面对表皮也有一定的锁合固定作用。因此阳极氧化的表面活化方法有可能成为有效的解决经皮生物密封的活化方法之一。     

纯钛表面微弧氧化法制备含羟基磷灰石氧化膜的实验研究

应用微弧氧化技术在纯钛表面制备含羟基磷灰石的氧化物膜.在氧化过程中,将钛试件放入含Ca、P电解液中,用直流脉冲电源处理.用扫描电镜(SEM)观察试件的表面和横断面形貌,X射线能谱(EDS)及X射线衍射(XRD)分析其元素成分和晶相结构.结果表明微弧氧化处理后,纯钛表面生成微孔结构的氧化膜,膜层厚度约20μm,由O、Ti、Ca和P四种元素组成.膜层表面有分布不均匀的火山丘状的微孔分布,直径小于5μm.膜层表面的钙磷原子比为1.63,界面处的钙磷原子比为0.51.膜层由金红石型和锐钛矿型二氧化钛及少量结晶相羟基磷灰石组成.微弧氧化技术在纯钛表面生成了内层致密外层多孔的晶相二氧化钛膜,同时含有少量羟基磷灰石,表明该技术在人工种植牙和人工骨关节等领域具有良好的医学应用前景.     

纯钛种植体的表面预备

钛的优良特性早已被公认为首选牙用种植材料，其表面氧化膜是形成骨融合的关键。为了进一步增加其耐腐蚀性和生物相容性，人们采取了多种方式进行表面处理，最终达到在植入体的不同部位产生不同的粗糙表面，以利于不同细胞在不同地方的附着，尽量提高其表面能，增加其生物活性，同时，达到避免各种污染物对纯钛种植体影响的目的。另外，由于无法控制种植体的表面电荷，因此，可以忽略其对种植体的影响作用     

A new chemical etching process to improve endosseous implant osseointegration: in vitro evaluation on human osteoblast-like cells

The development of novel mechanical and chemical surface modification treatments to improve the osteointegration properties of osseointegrated dental implants is nowadays a topic of great applicative interest. The aim of the present study was to analyse the role of surface topography and chemistry of four different surface treatments on titanium by an in vitro human osteosarcoma immortalised cell line model (MG63). The surface treatments considered were (a) machined titanium, (b) chemical etched on machined titanium, (c) sandblasted titanium and (d) chemical etching on sandblasted titanium. Chemical and physical surface properties were investigated by Scanning Electron Microscopy, Thin Film-X ray Diffraction and by Laser Profilometry. The in vitro biological response was characterised using the MG63 cell line by elution cytotoxicity tests, cell morphology, adhesion, proliferation activity, alkaline phosphatase activity and total DNA content in order to show a relationship between osteoblast response and surface features. Chemical and physical characterisation showed that the considered treatments differently modify the surface morphology in the micro and sub-micrometric scale. Although some differences in alkaline phosphatase activity were observed in the biological characterisation, depending on the specific material's surface finishing, the results showed that cells were well responsive on all the tested materials and grew and differentiated with similar proliferation rate.     

Wear properties of Ti and Ti-6Al-7Nb castings for dental prostheses

Titanium has been increasingly applied to dental prostheses because of its biocompatibility. However, application remains limited, due to the low strength and poor wear resistance of unalloyed titanium. The purpose of this study is to evaluate the wear resistance of high-strength Ti-6Al-7Nb alloy castings for dental application. Test specimens were cast from commercially pure titanium (CP-Ti grades 2 and 3) and Ti-6Al-7Nb alloy ingots, and subjected to a wear test simulating the occlusal loading pattern. Wear resistance was evaluated by the weight loss during the test. Ti-6Al-7Nb alloy was found to exhibit lower weight loss than CP-Ti. Moreover, scanning electron microscopic (SEM) observation after the test revealed that the worn surface of Ti-6Al-7Nb alloy is much smoother than that of CP-Ti. These results indicate that Ti-6Al-7Nb alloy castings can be used to produce dental prostheses of improved wear resistance and mechanical strength.     

Mold filling of titanium alloys in two different wedge-shaped molds

Pure titanium and titanium alloys are potential materials for the fabrication of cast dental appliances. One important factor in producing sound castings is the capacity of the metal to fill the mold. This study used a wedge-shaped mold to compare the mold filling of titanium with that of conventional dental casting alloys. The metals used were CP Ti, Ti-6Al-7Nb, Ti-6Al-4V, Ti with 1 and 4wt% Cu and ADA Type III gold alloy and an Ni-Cr alloy. The castings were cut into four pieces parallel to the triangular surface. Mold filling was evaluated as the distance between the tip of the cast wedge and theoretical tip of the triangle. The mold filling of the gold alloy was superior compared to all the metals tested, while the mold filling of the Ni-Cr alloy was the worst. There were no statistical differences at the 30 degrees marginal angle for all the cast titanium metals. At the sharper 15 degrees angle, CP Ti and Ti-6Al-7Nb was superior to both the Ti-Cu alloys. Although the mold filling of titanium was inferior compared to the gold alloy, the data justify the use of titanium for the production of dental appliances.     

Thin sol-gel-derived silica coatings on dental pure titanium casting

The sol-gel dipping process, in which liquid silicon alkoxide is transformed into a solid silicon-oxygen network, can produce a thin film coating of silica (SiO(2)). The features of this method are high homogeneity and purity of the thin SiO(2) film and a low sinter temperature, which are important in the preparation of coating films that can protect metallic ion release from the metal substrate and prevent attachment of dental plaque. We evaluated the surface properties of dental pure titanium casting coated with a thin SiO(2) or SiO(2)/F-hybrid film by the sol-gel dipping process. The metal specimens were pretreated by dipping in isopropylalcohol solution containing 10 wt% 3-aminopropyl trimethoxysilane and treated by dipping in the silica precursor solution for 5 min, withdrawal at a speed of 2 mm/min, air-drying for 20 min at room temperature, heating at 120 degrees C for 20 min, and then storing at room temperature. Both SiO(2) and SiO(2)/F films bonded strongly (above 55 MPa) to pure titanium substrate by a tensile test. SiO(2(-)) and SiO(2)/F-coated specimens immersed in 1 wt% of lactic acid solution for two weeks showed significantly less release of titanium ions (30. 5 ppb/cm(2) and 9.5 ppb/cm(2), respectively) from the substrate than noncoated specimens (235.2 ppb/cm(2)). Hydrophobilization of SiO(2(-)) and SiO(2)/F-coated surfaces resulted in significant increases of contact angle of water (81.6 degrees and 105.7 degrees, respectively) compared with noncoated metal specimens (62.1 degrees ). The formation of both thin SiO(2) and SiO(2)/F-hybrid films by the sol-gel dipping process on the surface of dental pure titanium casting may be useful clinically in enhancing the bond strength of dental resin cements to titanium, preventing titanium ions release from the substrate, and reducing the accumulation of dental plaque attaching to intraoral dental restorations.     

钛种植体表面改性策略及对骨整合的影响

背景：纯钛因具有优良的生物相容性、机械性能和与骨组织相近的弹性模量等被广泛应用于口腔种植领域。 目的：综述近年来钛金属种植体材料表面物理改性、化学改性和生物化学改性策略的研究进展。 方法：以“titanium,implant,surface modification,osseointegration”为检索词,检索PubMed数据库,以“钛,种植体,表面改性,骨整合”为检索词,检索中国知网数据库,限定时间范围为2007年1月至2013年2月。文献检索语种为英文和中文。纳入内容与钛种植体表面改性方法及其对骨整合影响密切相关的文献,排除重复文献。 结果与结论：计算机初检得到199篇文献,根据纳入排除标准,对其中76篇文献进行分析。钛种植体本身是生物惰性材料,通过表面改性对钛金属表面进行活化处理,使之具有生物功能性,与骨组织形成早期骨整合,是国内外口腔种植材料研究的热点问题。物理改性、化学改性和生物化学改性可缩短钛种植体种植周期,获得早期骨整合和更高的结合强度。今后的发展趋势是将多种改性方法有机结合,从分子水平深入研究钛金属材料表面与机体细胞和组织之间的界面分子作用机制,完善种植体的表面改性技术,实现种植体和骨组织的早期和更加稳定的骨整合。     

Bioactive macroporous titanium surface layer on titanium substrate

A macroporous titanium surface layer is often formed on titanium and titanium alloy implants for morphological fixation of the implants to bone via bony ingrowth into the porous structure. The surface of titanium metal was recently shown to become highly bioactive by being subjected to 5.0 M-NaOH treatment at 60 degrees C for 24 h and subsequent heat treatment at 600 degrees C for 1 h. In the present study, the NaOH and heat treatments were applied to a macroporous titanium surface layer formed on titanium substrate by a plasma spraying method. The NaOH and heat treatments produced an uniform amorphous sodium titanate layer on the surface of the porous titanium. The sodium titanate induced a bonelike apatite formation in simulated body fluid at an early soaking period, whereby the apatite layer grew uniformly along the surface and cross-sectional macrotextures of the porous titanium. This indicates that the NaOH and heat treatments lead to a bioactive macroporous titanium surface layer on titanium substrate. Such a bioactive macroporous layer on an implant is expected not only to enhance bony ingrowth into the porous structure, but also to provide a chemical integration with bone via apatite formation on its surface in the body.     

Inflammatory cytokine response to titanium chemical composition and nanoscale calcium phosphate surface modification

Nanoscale surface modification of titanium dental implants with calcium phosphate (CaP) has been shown to achieve superior bone wound healing and osseointegration compared with smooth or microrough titanium surfaces alone. As bone healing has been shown to be influenced by the action of cytokines, this study examined whether changes in cytokine gene expression from RAW 264.7 cells cultured on commercially pure and titanium alloy (Ti-6Al-4V) microrough or nanoscale crystalline CaP-modified surfaces, may influence downstream events in bone wound healing and osseointegration. Whilst no significant difference in the attachment or proliferation of RAW 264.7 cells was observed, the nanoscale CaP-modified surface elicited a gene expression profile with marked down-regulation of a number of pro-inflammatory cytokines and chemokines. Inflammatory cytokine gene expression was further influenced by chemical composition, with lower levels of pro-inflammatory markers noted following exposure of the macrophage-like cells to titanium alloy (Ti-6Al-4V) compared with the commercially pure titanium surface. Down-regulation of pro-inflammatory cytokine gene expression (confirmed at the protein level for TNFα and CCL5), may thus facilitate the enhanced bone wound healing and osseointegration observed clinically with nanoscale calcium phosphate-modified implant surfaces.