钛合金和钴铬合金表面细菌黏附的实验研究

目的比较钛合金(Ti-6Al-4V)和钴铬合金(Chromium-Cobalt alloy)表面口腔变形链球菌黏附能力的大小,研究表面粗糙度与细菌黏附的关系。方法将不同表面粗糙度的钛合金和钴铬合金试件进行变形链球菌体外黏附试验,采用菌落形成计数法测定试件表面的细菌黏附量。结果钛合金组的细菌黏附量少于钴铬合金组。二者的细菌黏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利于减少由细菌引起的并发症,同时修复体表面严格的研磨抛光也能有效减少由细菌引起的并发症。     

不同消毒方法对TiO2涂层种植体抗菌性能的影响

目的研究不同消毒方法对TiO₂涂层种植体抗菌性能的影响。方法纯钛表面经0.5%质量分数的氢氟酸酸蚀后阳极氧化,制备TiO₂涂层试样作为实验组,以未经处理的纯钛试样作为对照组。采用乙醇浸泡、高压蒸汽灭菌、紫外线照射3种消毒方法处理试样。观察试样表面形貌,测量试样表面粗糙度及消毒前后去离子水在试样表面接触角,评价试样的细菌黏附能力;采用薄膜密着法进行活菌计数,验证经3种消毒方法处理后,试样抑制金黄色葡萄球菌的功效;采用场发射扫描电镜观察3种消毒方法对细菌形态的影响。结果与对照组试样相比,实验组的表面粗糙度更大,对细菌黏附能力更强。经紫外线照射消毒后,试样表面接触角小于乙醇浸泡消毒和高压蒸汽灭菌。活菌计数和场发射扫描电镜观察显示,乙醇浸泡消毒后,试样表面活菌数最多,细菌形态较完整;高压蒸汽灭菌后,试样表面活菌数较少,细菌形态受到一定程度破坏;紫外线照射消毒后,试样表面活菌数最少,细菌形态破坏最完全。结论经紫外线照射消毒后,试样的抗菌性能最佳,高压蒸汽灭菌次之,乙醇浸泡消毒效果最差。     

氧化锆基台与钛基台细菌黏附的比较

目的:通过实验,观察细菌与菌斑在瓷沉积种植基台和钛基台上的黏附量,分析两种不同材料对细菌黏附及影响。方法:分别将氧化锆陶瓷与钛合金制作成10mm×10mm×2mm的试片,每组六片。试件表面依次用200#、400#、600#、1000#、1200#(氧化锆陶瓷在1200#水磨砂纸磨光后用松风产陶瓷抛光轮抛光)1500#、2000#,砂纸磨光。将个样本置于变形链球菌的培养液中,在37℃条件下,静态培养后培养1h。荧光显微镜下计数黏附细菌的数量。结果:氧化锆陶瓷试件粘附细菌数量少于钛合金试件黏附细菌数量(P<0.01)。结论:氧化锆陶瓷具有优良的生物学性能。一定程度上可减少细菌附着定植水平,可降低种植体周围炎的发生。     

钛合金表面改性对细菌黏附的影响

目的研究钛合金表面改性形成氨化钛膜对细菌黏附能力的影响.方法制作钛合金试件144件,随机选出72件,采用多弧离子镀法在其表面改性形成氨化钛膜,钛合金为对照组,镀膜后钛合金为实验组.在实验组和对照组试件表面黏附血链球菌、黏性放线菌、白色念珠菌,分别进行细菌体外黏附实验.用菌落形成单位计数法统计分析氨化钛膜形成前后各种细菌黏附量的变化.结果在细菌黏附24、48、168h,上述3种细菌在实验组表面黏附量较对照组表面黏附量显著减少(P<0.001).结论钛合金表面改性形成氨化钛膜可抑制细菌黏附.     

钛表面载银抗菌功能膜的抑菌性研究

目的 通过对钛片进行表面处理制备出载银抗菌功能膜,研究处理前后钛片对种植体周围炎易感细菌的抑菌性能.方法 利用微弧氧化法在钛表面制备陶瓷层,运用光催化沉积将银离子沉积于陶瓷层表面,制得含银离子的杭菌功能膜;采用扫描电镜观察钛片处理前后表面形貌及抗细菌黏附性能;通过计算抑菌率研究处理前后钛片对牙龈卟啉单胞菌及金黄色葡萄球...     

Ti-6Al-7Nb 喷砂酸蚀处理后对大鼠成骨细胞的影响

摘要 目的 纯钛（Ti）和Ti-6Al-7Nb(TC20)经机械打磨和喷砂酸蚀(SLA)两种不同方法处理后,研究其内部结构、表面能对小鼠成骨细胞的影响。方法 选取纯钛和Ti-6Al-7Nb钛片若干分为实验组和对照组,对照组直接用砂纸机械打磨,实验组用含有Al203的大颗粒石英砂和配比好的酸蚀液喷砂酸蚀两种钛片表面,将从小鼠中提取的成骨细胞接种于钛片上,使用低倍数显微镜观察经过不同处理的两种钛片表面形貌,接触角测量仪分析钛片表面亲水性,将喷砂酸蚀处理的两种钛片放入模拟体液(SBF)中7d、14d、21d后用扫描电镜(SEM)、X线衍射仪(XRD)观察样品表面沉积物形貌、物相,扫描电镜观察小鼠成骨细胞形貌,MTT测量小鼠成骨细胞增殖情况。结果 纯钛和Ti-6Al-7Nb打磨组表面呈机械划痕,喷砂酸蚀组表面拥有大量孔洞形貌,喷砂酸蚀处理后的钛片表面为亲水性结构,样品浸入模拟体液14天后Ti-6Al-7Nb表面最先观察到表面覆盖的羟基磷灰石涂层, 样品浸入模拟体液后21d,Ti和Ti-6Al-7Nb表面都观察到羟基磷灰石涂层,小鼠成骨细胞大量附着在喷砂酸蚀处理的钛片表面,经统计学分析成骨细胞在喷砂酸蚀组表面增殖能力强于光滑组（P<0.05）。结论 喷砂酸蚀处理的Ti-6Al-7Nb有利于成骨细胞的黏附, 羟基磷灰石涂层有利于促进种植体与骨组织的结合。     

氮离子溅射对钛合金表面细菌黏附的影响

目的研究氮离子溅射对钛合金表面细菌黏附能力的影响。方法制作钛合金试件144件,随机选出72件,采氮离子溅射法对其表面改性,钛合金组为对照组,氮离子溅射组为实验组。在实验组和对照组试件表面粘附血型链球菌、黏性放线菌、白色念珠菌,分别进行细菌体外黏附实验。用菌落形成单位计数法统计分析氮离子溅射前后各种细菌黏附量的变化。结果在细菌黏附24、48、168h,上述3种细菌在实验组表面黏附量较对照组表面黏附量显著减少(P<0.001)。结论氮离子溅射可抑制钛合金表面细菌黏附。     

应用微弧氧化-水热处理法在纯钛表面制备生物梯度陶瓷涂层

目的 应用微弧氧化和水热处理技术在纯钛表面制备TiO2/HA梯度涂层,并对该涂层成分、形貌等理化性能进行评价.方法 纯钛试件分为三组,分别进行微弧氧化处理(M组)、微弧氧华-水热处理(M H组)和纯钛对照(C组).采用扫描电镜观察表面形貌并用X线衍射对其进行成分分析,通过划痕实验检测膜基结合力.结果 做弧氧化处理后试件表面呈现多孔状,主要为锐钛矿型TiO2;经过后续水热处理,从扫描电镜(SEM)照片可以看到试件表面析出一层白色柱形结晶体,同时X射线衍时仪(XRD)潜线出现了羟基磷灰石的衍射峰.结论 微弧氧化及水热处理能够增强纯钛种植体的生物相容性.     

钛合金种植体在牙列缺损修复中的应用价值

目的 探讨钛合金种植体对牙列缺损修复中的应用价值。方法 将88例牙列缺损患者依据不同种植体设计方案分为钛合金组和纯钛组各44例。观察对比两组患者牙龈指数变化、修复满意度与咀嚼效率以及不良反应情况。结果 钛合金组修复后的牙龈指数明显低于纯钛组,差异有统计学意义(P<0.05);钛合金组的咀嚼率、满意度均显著高于纯钛组,差异有统计学意义(P<0.05);钛合金组的不良反应率明显低于纯钛组,差异有统计学意义(P<0.05)。结论 钛合金种植体修复方案对于牙列缺损患者的效果明显优于纯钛种植体,修复效果更佳,患者较为认可,修复满意度高。     

纯钛种植体表面的飞秒激光制备及其短期植入研究

目的:观察飞秒激光处理种植体表面对种植体-骨界面结合强度及种植体早期骨结合的作用。方法:应用飞秒激光处理浸没于羟基磷灰石(HA)过饱和溶液中的纯钛试样表面作为实验组,未处理组为对照组,用扫描电镜和能谱仪分析试样表面形貌及元素组成;将试样植入新西兰大白兔股骨4周后制作组织学切片来观察实验组试样的早期成骨性及骨诱导性。结果:扫描电镜下实验组试样表面的图案化结构由尖峰状和沟槽状结构组成,在尖峰状突起和沟槽之间可见与基体紧密结合的负载物,能谱分析显示负载物的主要成分为Ti、Ca、P、O,对照组试样表面光滑,仅见机械加工的划痕。组织学结果显示,与对照组相比,实验组试样表面类骨质、钙磷盐的沉积更加活跃。结论:飞秒激光能在浸没于过饱和HA溶液中的纯钛试样表面形成多层图案化的拓扑结构,并同时负载Ca/P元素,有利于种植体的早期成骨及初期稳定性。     

Investigations into the reduction of powder adhesion to stainless steel surfaces by surface modification to aid capsule filling

The adhesion force of powder particles to stainless steel surfaces, which had been modified by various metal coatings, has been measured using a centrifuge technique. The surfaces were characterised by surface roughness and surface free energy measurements, whereas the particles, which had a particle size of 32-45 microns, were characterised by their surface free energy only. The roughness of the surfaces was found to be similar, so that changes in the adhesion properties of the powders to these surfaces could not be due to a change in this surface property. However, there was a major difference in the surface free energy parameters of the surfaces. The surface free energy varied from a nearly non-polar character to strong Lewis-base. The adhesion force of pregelatinised starch and lactose monohydrate particles increased with the increasing base character of the surfaces. In principle this behaviour could also be seen for calcium carbonate particles. However, here the order of the adhesion forces to the surfaces tested was disrupted on one occasion because of a pronounced influence of particle and surface hardness on this property. In general, the ranking of the adhesion forces matched observations made during capsule filling on a Bosch GKF-400 tamp-filling machine. It was therefore concluded that a metal coating of the tamping pins would be able to reduce powder adhesion. In order to identify the best coating, centrifugal adhesion force measurements could be undertaken, or surface free energy measurements could be made. The results found suggest that a surface finish by means of chromium nitride coating provided, in most cases, a significant reduction of the powder adhesion. For very hard powder particles such as inorganic excipients the hardness of the surfaces must also be increased. In these cases plasma-coating of chromium appears helpful.     

Antibacterial activity and biofilm inhibition by surface modified titanium alloy medical implants following application of silver,titanium dioxide and hydroxyapatite nanocoatings

One of the most common causes of implant failure is peri-implantitis, which is caused by bacterial biofilm formation on the surfaces of dental implants. Modification of the surface nanotopography has been suggested to affect bacterial adherence to implants. Silver nanoparticles are also known for their antibacterial properties. In this study, titanium alloy implants were surface modified following silver plating, anodisation and sintering techniques to create a combination of silver, titanium dioxide and hydroxyapatite (HA) nanocoatings. Their antibacterial performance was quantitatively assessed by measuring the growth of Streptococcus sanguinis, proportion of live/dead cells and lactate production by the microbes over 24?h. Application of a dual layered silver–HA nanocoating to the surface of implants successfully inhibited bacterial growth in the surrounding media (100% mortality), whereas the formation of bacterial biofilm on the implant surfaces was reduced by 97.5%. Uncoated controls and titanium dioxide nanocoatings showed no antibacterial effect. Both silver and HA nanocoatings were found to be very stable in biological fluids with material loss, as a result of dissolution, to be less than 0.07% for the silver nanocoatings after 24?h in a modified Krebs-Ringer bicarbonate buffer. No dissolution was detected for the HA nanocoatings. Thus, application of a dual layered silver–HA nanocoating to titanium alloy implants creates a surface with antibiofilm properties without compromising the HA biocompatibility required for successful osseointegration and accelerated bone healing.     

纳米羟基磷灰石抑制变形链球菌粘附的体外研究

目的：研究纳米羟基磷灰石（Nano-HA）对变形链球菌附着力的影响。方法：将不同浓度的Nano-HA溶液加入到轻唾液体培养基中培养变形链球菌,2d后测定粘附于变形链球菌吸附板表面变形链球菌量．并进行比较;对已附着变形链球菌的吸附板放入Nano-HA溶液中,观察变形链球菌的脱落情况。结果：Nano-HA对变链菌的附着有抑制作用和对已附着的变形链球菌有解粘附的作用。结论：Nano-HA对变链菌的粘附有显著的抑制作用。     

钛种植体表面原位包裹大鼠骨髓基质细胞的研究

目的探讨钛种植体表面对大鼠骨髓基质细胞（bone marrow stromal cells,BMSCs）进行原位包裹的方法,为钛种植体表面组织工程支架构建提供实验基础。方法采用层层自组装技术在钛种植体表面构建以壳聚糖/海藻酸钠为组分的聚电解质多层膜结构,同时对BMSCs进行原位分层包裹,并通过扫描电镜及激光共聚焦显微镜观察包裹细胞的生长状态。结果扫描电镜及激光共聚焦显微镜观察证实BMSCs被成功包裹于钛种植体表面,并保持良好的生物学活性。结论钛种植体表面可以实现对BMSCs的原位分层包裹。     

Evaluation of Osseointegration around Tibial Implants in Rats by Ibandronate-Treated Nanotubular Ti-32Nb-5Zr Alloy

Materials with differing surfaces have been developed for clinical implant therapy in dentistry and orthopedics. This study was designed to evaluate bone response to titanium alloy containing Ti-32Nb-5Zr with nanostructure, anodic oxidation, heat treatment, and ibandronate coating. Rats were randomly assigned to two groups for implantation of titanium alloy (untreated) as the control group and titanium alloy group coated with ibandronate as the experimental group. Then, the implants were inserted in both tibiae of the rats for four weeks. After implantation, bone implant interface, trabecular microstructure, mechanical fixation was evaluated by histology, micro-computed tomography (μCT) and the push-out test, respectively. We found that the anodized, heat-treated and ibandronate-coated titanium alloy triggered pronounced bone implant integration and early bone formation. Ibandronate-coated implants showed elevated values for removal torque and a higher level of BV/TV, trabecular thickness and separation upon analysis with μCT and mechanical testing. Similarly, higher bone contact and a larger percentage bone area were observed via histology compared to untreated alloy. Furthermore, well coating of ibandronate with alloy was observed by vitro releasing experiment. Our study provided evidences that the coating of bisphosphonate onto the anodized and heat-treated nanostructure of titanium alloy had a positive effect on implant fixation.     

Investigation of the extent of surface coating via mechanofusion with varying additive levels and the influences on bulk powder flow properties

The objective of this study was to investigate if the coating extent created by a mechanofusion process corresponded with observed changes in bulk powder properties. A fine lactose powder (approximate median diameter 20 μm) was dry coated with magnesium stearate using from 0.1 to 5% (w/w) content. An ultra-thin coating layer of magnesium stearate was anticipated, but previous attempts to determine such thin layers on these fine particles have had limited success, with poor resolution. In this study, the surface coating was examined using the state-of-the-art XPS and ToF-SIMS systems. The powder flow was characterized by Carr index and shear cell testing. XPS was successfully applied to demonstrate variations in surface coverage, as a function of additive levels, and indicated near complete coating coverage at additive levels of 1% (w/w) and above. ToF-SIMS results supported such coating coverage assessment, and indicated coating uniformly across the fine particle surfaces. The flow metrics employed could then be related to the coating coverage metrics. The mechanofusion process also modified the apparent surface roughness observed by SEM and BET. It was suggested that the changes in the surface chemical composition exerted a more evident and direct impact on the powder cohesion and flow characteristics than the changes in the surface morphological properties after the mechanofusion in this study.     

钛种值体表面处理后的超微结构观察和周围骨密度的定量研究

本文运用机械抛光、喷砂和电解浸蚀表面处理技术,获得不同表面结构的钛种植体,Ｄｉｇｏｒａ牙科数字扫描仪对种植体一骨界面的不同骨区的骨密度值测量,将测得的皮质骨和松质骨的骨密度值进行统计学分析,结果表明电解浸蚀处理技术制备的微孔表面并有一定厚度氧化层和钛种植体周围具有较高的骨密度值。     

Tablet surface characterisation by various imaging techniques

The aim of this study was to characterise tablet surfaces using different imaging and roughness analytical techniques including optical microscopy, scanning electron microscopy (SEM), laser profilometry and atomic force microscopy (AFM). The test materials compressed were potassium chloride (KCl) and sodium chloride (NaCl). It was found that all methods used suggested that the KCl tablets were smoother than the NaCl tablets and higher compression pressure made the tablets smoother. Imaging methods like optical microscopy and SEM can give useful information about the roughness of the sample surface, but they do not provide quantitative information about surface roughness. Laser profilometry and AFM on the other hand provide quantitative roughness data from two different scales, laser profilometer from 1 mm and atomic force microscope from 90 microm scale. AFM is a powerful technique but other imaging and roughness measuring methods like SEM, optical microscopy and laser profilometry give valuable additional information.     

Surface characterization by atomic force microscopy of sterilized PLGA microspheres

Atomic force microscopy (AFM) is recognized a suitable and powerful technique for surface and morphological analysis. Even if until now this technique has not been frequently used in the pharmaceutical field, it can contribute to an accurate morphologic characterization of microspheres and nanospheres. In this work, atomic force microscopy has been used to perform the surface characterization of sterilized microspheres. The aim is to investigate the morphologic modifications induced by gamma irradiation on poly(lactide-co-glycolide) microspheres loaded with ovalbumin and to compare the results obtained by AFM to those obtained by scanning electron microscopy (SEM). The results obtained show that, with respect to SEM, AFM can give some additional information regarding the modifications induced by gamma-irradiation on microspheres surface morphology. The significant changes in surface roughness after irradiation are indicative of damage due to gamma-irradiation. The unchanged surface roughness values calculated for microspheres containing PEG in their matrix, suggest that this polymer exerts a protective effect towards gamma-irradiation.