载银多聚赖氨酸-海藻酸钠静电自组装多层膜修饰钛表面及其抗菌研究

目的 利用层层自组装技术在钛表面构建聚L赖氨酸（PLL）-海藻酸钠（ALG）多层膜,并在膜层中导入纳米银颗粒,以评价其杀菌效果。方法 利用层层自组装的方法将带正电荷的PLL与带负电荷的ALG在钛片上交替吸附沉积形成聚电解质多层膜,再用盐诱导相分离技术在多层膜中形成一定尺寸的微孔并在其中包裹纳米银粒子。扫描电子显微镜（SEM）、傅立叶红外光谱（FTIR）和能谱分析（EDX）对表面进行表征。并与变形链球菌共培养,观察对细菌的粘附和杀灭的作用。结果 SEM、FTIR和EDX分析证实：多层膜成功沉积在钛片表面,并且纳米银粒子被包裹于其中。荧光显微镜显示纯钛表面有大量的活细菌,沉积聚电解质多层膜后细菌数量减少,导入纳米银离子之后附着于钛片上的细菌数量更少,并且随着膜层数的增多,银离子含量增加,抗菌效果也增强。SEM结果与荧光结果一致。结论 通过层层自组装的方法在钛金属表面沉积载银PLL-ALG聚电解质多层膜,能抑制细菌的粘附。同时,随着膜层数的增加,银粒子含量增加,抗菌效果增强。     

钛表面儿茶酚化聚电解质多层膜对蛋白质的吸附研究

目的探讨钛表面儿茶酚化聚电解质多层膜对蛋白质的吸附行为,为钛种植体表面改性提供参考。 方法根据本课题组前期建立的方法,采用脂多糖胺纳米囊泡（NPs）和3,4-二羟苯基丙酸反应制备儿茶酚接枝率为40%的儿茶酚化NPs（cNPs）;采用透明质酸（HA）和多巴胺反应制备儿茶酚接枝率为10%的儿茶酚化透明质酸（cHA）。利用层层自组装技术,以cNPs为引发层、cHA/NPs为阴、阳离子聚电解质,在钛或石英表面构建含3个（cHA/NPs）双层的儿茶酚化聚电解质膜[（基底-cNPs-（cHA/NPs）₃],记为cPEM。同时以NPs为引发层,构建含（HA/NPs）₃的未儿茶酚化聚电解质膜（PEM）。采用红外光谱分析膜表面化学组成、激光扫描共聚焦显微镜（LSCM）检测膜表面粗糙度,Zeta电位分析仪记录膜表面Zeta电位。选取4种等电点（pI）分别小于、等于、大于生理pH 7.4的蛋白质：牛血清白蛋白（BSA,pI = 4.7）、纤连蛋白（Fn,pI = 5.8）、牛血红蛋白（BHb,pI = 6.8 ~ 7.0）、多聚赖氨酸（PLL,pI = 9.74）,以其为模型蛋白,用0.15 mol/L的NaCl配制成1 mg/mL的水溶液。采用石英晶体微天平（QCM）实时动态监测膜表面蛋白吸附情况、原子力显微镜观察样品蛋白吸附前后形貌,LSCM、荧光酶标仪分别分析荧光标记蛋白在膜表面吸附情况,并测试荧光标记蛋白的吸附量。使用SPSS 20.0对数据进行单因素方差分析、SNK和LSD法进行比较,P<0.05认为差异有统计学意义。 结果LSCM结果表明,石英表面粗糙度为（301 ± 12）nm,组装cPEM、PEM后,表面粗糙度增加,分别为（656 ± 88）、（446 ± 25）nm,组间差异具有统计学意义（F = 66.974,P<0.001）。cPEM组的红外谱图中出现儿茶酚中的苯环（ν_{C = C}）、PEM组的胺基和烷基、多糖中的糖醛酸环等特征峰,证实钛表面引入cPEM和PEM。组装过程中Zeta电位呈锯齿状交替上升,cPEM组表面电位为+22.53 mV,PEM组的表面电位为+17.36 mV。QCM结果表明,生理pH下,所有表面均基本不吸附PLL。在不同表面,BSA和BHb的吸附量cPEM组>PEM组>Ti组。原子力显微镜下可见cPEM、PEM组表面为分布均匀的水滴形海岛状结构,吸附BSA后,表面可见圆盘状结构,且cPEM组量大于PEM组,说明可能BSA在cPEM组表面的吸附量大于PEM组。采用LSCM和荧光酶标仪分析绿色荧光标记蛋白在不同表面的吸附情况,发现在不同种膜表面,同一蛋白吸附量cPEM组>PEM组>Ti组;在同一种膜表面,不同蛋白吸附量BSA>Fn>BHb。 结论本实验研发的聚电解质多层膜对钛表面进行改性后,能提高蛋白在表面的吸附,儿茶酚化改性则进一步促进这种吸附。蛋白吸附的驱动力可能主要源于静电相互作用和儿茶酚基团对蛋白偶联捕捉作用。     

钛表面自组装聚L-赖氨酸和海藻酸钠多层膜对成骨细胞增殖和分化的影响

目的在钛表面沉积聚L-赖氨酸(PLL)和海藻酸钠(ALG)聚电解质多层膜,以评价其对成骨细胞增殖和分化的影响。方法用层层自组装的方法在钛表面沉积PLL和ALG,形成Ti-(PLL-ALG)10-PLL涂层,用傅里叶变换红外光谱(FTIR)和扫描电子显微镜(SEM)对涂层进行表征。以纯钛作为对照组,Ti-(PLL-ALG)10-PLL作为实验组,分别在其表面进行MC3T3细胞培养,1d、3d、5d和7d后用CCK-8检测细胞增殖率,用ALP检测碱性磷酸酶的活性。结果 FTIR和SEM显示PLL和ALG已沉积到钛表面。MC3T3细胞在Ti-(PLL-ALG)10-PLL表面的增殖率在第1天和3天时明显高于对照组,P值分别为0.04和0.028;第5天和7天则无显著性差异(P>0.05)。第7天和14天Ti-(PLL-ALG)10-PLL组碱性磷酸酶值明显高于对照组,P值分别为0.08和0.02。结论通过层层自组装的方法在钛种植体表面沉积Ti-(PLL-ALG)10-PLL聚电解质多层膜能促进MC3T3细胞在其表面的增殖和分化。     

钛种植体表面改性方法

钛种植体具有美观舒适、不损伤邻牙、临床效果显著等优点,广泛应用于口腔种植修复领域;但应用中存在骨结合失败、种植体周围骨吸收、种植体周围炎等问题,使其应用受到一定的限制。对钛种植体进行表面改性,在其表面制备不同的理化涂层和生物活性涂层,可以提高种植体的种植成功率,满足临床应用需求。本文从物理、化学、生物三方面对各种钛种植体表面改性方法的特点进行总结,为牙种植材料的研究和临床应用提供参考。     

钛种植体表面微结构对成骨细胞影响的研究进展

钛种植体表面形貌是钛种植体表面改性的研究热点之一。种植体表面形貌主要有光滑、粗糙和多孔结构3类。种植体表面形貌对种植体一骨界面的成骨活性产生不同的影响。本文综述了种植体表面微结构对种植体一骨组织界面成骨细胞的生物学行为的影响，为研究和设计种植体表面微结构提供参考。     

纯钛种植体表面抗菌改性的研究进展

纯钛种植体部分暴露于口腔中,在种植体植入、愈合和行使功能的各环节中,种植体周组织均存在着被细菌感染的危险。细菌附着在种植体上会影响新生骨的生长,导致支持骨的丧失,从而降低骨一种植体界面的机械稳定性,这是种植体失败的主要原因之一。因此控制种植体表面细菌聚集和粘附,对于预防和治疗种植体周感染具有重要意义。本文就纯钛种植体表面抗菌改性的研究进展作一综述。     

钛表面接枝溴代十六烷后的杀菌效果研究

目的 在钛表面沉积透明质酸(HA)和壳聚糖(CHI)聚电解质多层膜,并用溴代十六烷对CHI上的氨基季铵化,以评价其杀菌效果.方法 在碱化处理过的钛片上吸附带正电荷的聚乙烯亚氨(PEI),再用层层自组装的方法在钛表面交替沉积带负电荷的HA和带正电荷的CHI,并用溴代十六烷(C16H33Br)对CHI上的氨基季铵化,形成Ti-PEI-(HA-CHI)20-N+(C16H33)3Br涂层,扫描电子显微镜(SEM)对涂层断面进行表征;以纯钛为对照组,Ti-PEI-(HA-CHI)20和Ti-PEI-(HA-CHI)20-N+(C16H33)3Br-为实验组,分别在其表面进行变形链球菌(S.m)培养24h后用荧光显微镜和SEM检测钛片表面的细菌活性.结果 SEM显示聚电解质多层膜已沉积到钛片表面并具有一定的厚度.荧光显微镜显示纯钛表面有大量的活细菌,Ti-PEI-(HA-CHI)20上细菌数量较少,且有部分死菌;而Ti-PEI-(HA-CHI)20-N+(C16H33)3Br-上细菌几乎全为死菌.SEM结果显示纯钛、Ti-PEI-(HA-CHI)20、Ti-PEI-(HA-CHI)20-N+(C16H33)3Bf 3组钛片上的细菌数量依次减少.结论 钛表面沉积HA/CHI聚电解质多层膜,并对多层膜中的CHI季铵化后,其表面具有显著的杀菌作用.     

钛种植体表面处理对骨整合的影响

钛种植体表面处理如机械及微机械加工,喷砂酸蚀,微弧氧化,表面纳米化和生物化学方法都会促进种植体的骨整合能力.本文就钛种植体的表面处理对骨整合的影响作一综述.     

纯钛表面聚吡咯涂层的表面性能研究

目的：纯钛表面电化学聚合聚吡咯涂层并研究其表面性能。方法：采用恒电流法以0.25mA/cm^3、1mA/cm^2、4mA/cm^2的电流密度制备两种支撑电解质Cl^-和ToS^-的纯钛表面聚吡咯涂层。利用SEM、表面粗糙度仪以及接触角测量仪检测涂层表面性能。结果：随聚合电流密度增大，表面粗糙度（Ra、Rz值）和表面接触角逐渐增大，而表面自由能逐渐减小。在相同的聚合密度电流下，ToS^-搀杂组的表面粗糙度（Ra、Rz值）、表面接触角均大于Cl^-搀杂组；而表面自由能则小于Cl^-搀杂组。结论：聚吡咯的表面性质，如表面形貌、润湿性、表面自由能，可以通过改变搀杂离子种类和聚合电流密度来进行调整。     

钛种植体表面处理方法的研究新进展

钛种植体的表面处理对提高种植成功率起着重要作用,不同处理方法都有其优点,但共同的特点是形成粗糙表面,使其具有更好的生物活性和骨结合能力.寻找一种能兼具各方优点,更好地促进骨结合的表面处理方法,已成为近年来种植学研究的热点.     

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提要：钛和钛合金因具有良好的机械力学性能和生物相容性被广泛用作牙科种植体。种植体植入机体后,与骨的骨性结合是关系到种植体在体内维持时间长短的关键。种植体进入机体后,首先是其表面与组织接触,因此对种植体表面改性是提高种植体与骨的骨性结合的有效方法。本文对目前钛和钛合金表面改性的方法进行简要概述。     

种植体表面抗菌技术的分类与研究进展

随着种植体在口腔领域的广泛应用,口腔种植体相关的感染成为威胁种植体远期疗效的重大隐患。种植体表面的菌斑和生物膜与感染密切相关,一种有效的途径是通过种植体表面抗菌技术处理以防止微生物的聚集与粘附,本文就种植体表面抗菌技术的分类与研究进展作一综述。     

银的抗菌性能及其在种植体表面的抗菌改性研究

种植体周围细菌黏附聚集导致的种植体周炎是种植体失败的重要原因。抑制种植体表面的细菌黏附和杀灭种植体周的细菌对防治种植体周炎具有重要意义。本文就银的抗菌性能及在种植体表面抗菌改性的研究进展作一综述。     

Immediately loaded titanium implants with a porous anodized surface with at least 36 months of follow-up

Background: Results from some studies clearly suggest that immediate loading can achieve equal success rates as those found in delayed or unloaded implants. There is still a lack of knowledge about the role of surface oxide properties during the peri‐implant bone healing processes. Purpose: The aim of this study was a clinical follow‐up study of immediately loaded implants with a porous anodized surface. Materials and Methods: A total of 142 TiUnite^TM (Nobel Biocare, Göteborg, Sweden) implants were inserted from January to September 2001. All implants have been used in fixed restorations. Fifty implants were inserted in completely edentulous mandibles, and 69 implants were inserted in completely edentulous maxillae. All 119 implants were subjected to immediate functional loading (IFL) (immediate restoration with full occlusal contact). The other 23 implants, inserted in 12 patients, underwent immediate nonfunctional loading (INFL) (immediate restoration without occlusal contact) in different anatomical configurations (single tooth, small bridges in the anterior mandible, anterior maxilla, and posterior maxilla). All 142 implants have been followed for at least 3 years. Results: All implants appeared to be osseointegrated from a clinical and radiographic point of view. No failures were observed in the IFL and INFL groups. The implant success was 100%. The mean marginal bone loss was 0.8 and 1.0 mm at 12 and 36 months, respectively. Conclusion: Implants with a porous anodized surface appear to work well under an immediate loading state in the long term.     

Oxidized titanium implants (Nobel Biocare TiUnite) compared with turned titanium implants (Nobel Biocare mark III) with respect to implant failure in a group of consecutive patients treated with early functional loading and two-stage protocol

OBJECTIVES: The purpose of this study was to compare two implant types of similar shape but with different surfaces with respect to implant failure. MATERIAL AND METHODS: A total of 136 patients were treated with Nobel Biocare Implants between January 2001 and December 2002. Totally 394 implants were placed, of which 199 were oxidized titanium implants (Nobel Biocare TiUnite and 195 with turned titanium surface (Nobel Biocare Mark III. Sixty-three patients underwent a one-stage surgical protocol, of which 24 were objected to early functional loading. The remaining 73 patients were treated with a traditional two-stage surgical protocol. All patients were followed for a minimum of 5 months after loading of the implants. Implants were classified as survivals when clinically stable and fulfilling purported function without any discomfort to the patient, with no signs of infection or ongoing pathologic process. RESULTS: Seven implants were lost in five patients (two males and three females), six in the maxilla and one in the mandible. All failed implants were Mark III implants, inserted following the traditional two-stage protocol. The implant success rate was 98.2% for the whole-patient group, divided as a 100% success rate following the implants with oxidized surface (Nobel Biocare TiUnite compared with a success rate of 96.4% with implants with turned surface (Nobel Biocare Mark III).     

Surface modification of titanium by etching in concentrated sulfuric acid

OBJECTIVE: The purpose of this study was to characterize the etching behavior of titanium in concentrated sulfuric acid and discuss its application on surface modification of titanium for biological use. METHODS: Commercially pure titanium (cpTi) plate was etched in 48% H2SO4 at RT -90 degrees C for 0.25-8 h. The weight loss was derived from the weight differences before and after etching. The surfaces after etching were characterized by surface roughness, X-ray diffractometry, and scannning electron spectroscopy. The apparent activation energy of the dissolution of cpTi into acid was derived from an Arrhenius plot of the rate of weight loss versus the acid temperature. RESULTS: The surface roughness of cpTi increased with the acid temperature and etching time. The surface roughness was strongly related to the weight loss. The weight loss increased drastically with the acid temperature after an initial period, which shortened with increasing acid temperature. The apparent activation energy for the dissolution of cpTi in H2SO4 was derived as 67.8 kJ/mol. SIGNIFICANCE: This study indicates that etching with concentrated sulfuric acid is an effective way to modify the surface of titanium for biological applications.