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101.
目的 分析比较颅骨大骨瓣缺损早/晚期行钛网数字化成形修补术的有效性、安全性及对预后的影响.方法 选取2012年1月至2013年12月颅脑创伤或行脑出血行去大骨瓣减压术112例,76例在去大骨瓣减压术后38.9(32~52)d行钛网数字化成形修补术(早期修补组);36例在去大骨瓣减压术后114.2(90~153)d进行修补(晚期修补组).分析比较2组手术耗时、皮瓣游离时间、手术失血量、并发症,以及术后患者的日常生活活动能力(ADL)评分、Fugl-Meyery评分、神经功能缺损评分、认知功能恢复.结果 早期修补组与晚期修补组的手术时间分别为(92.33±13.71) min与(141.67±18.12)min;皮瓣游离时间为(13.29±3.43) min与(38.56±7.35) min;手术出血量分别为(352.36±21.83) ml与(523.53±32.51)ml,差异具有统计学意义(P<0.01).早期修补组的硬膜下积液率及皮瓣游离过程中硬膜破裂率明显少于晚期修补组,差异具有统计学意义(P<0.01).早期修补组ADL及Fugl-Meyery评分均较晚期修补组明显提高,差异具有统计学意义(P<0.05或P<0.01);而神经功能缺损评分明显降低,差异具有统计学意义(P<0.05).蒙特利尔认知评估量表提示早期修补组认知功能恢复明显优于晚期修补组,差异具有统计学意义(P<0.05).结论 颅骨大骨瓣缺损早期行钛网数字化成形修补术优于晚期,早期颅骨修补利于软组织分离,减少出血,改善预后.钛网数字化成形技术可确保修复钛网与颅骨缺损部位精确合体,显著缩短手术时间,减少手术风险;钛网数字化成形早期颅骨修补术值得临床推广. 相似文献
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104.
钛基种植体表面抗菌改性的研究进展 总被引:1,自引:0,他引:1
钛金属以其优异的生物相容性、高机械强度和良好的抗腐蚀性被广泛用于临床牙列缺损及牙列缺失的修复治疗,然而细菌容易聚集和黏附其表面,且钛金属自身不具有抗菌性能,是种植体周围炎和种植义齿修复失败的主要原因之一。钛表面抗菌改性可改变种植体表面的理化性能,抑制致病菌的黏附和聚集,提高种植义齿修复的成功率。钛种植体表面改性主要是将抗菌剂或有抗菌性能的物质通过羟磷灰石涂层、二氧化钛纳米管和脱乙酰壳多糖等具有一定抗菌性能的载体对钛金属基体进行表面修饰,从而赋予钛金属不同程度的抗菌性能。本文就基体、载体和抗菌剂三方面的钛基种植体表面改性等研究进展作一综述。 相似文献
105.
抗菌肽广泛存在于多种生物体内,是生物体非特异性免疫功能的重要组成部分。其可以保护机体免受细菌、真菌、寄生虫和病毒等病原体的侵袭,还具有介导催化、凋亡、免疫调节活性、促进伤口愈合和促成骨等作用,是钛金属内植物表面抗菌涂层研究的热点,具有良好的应用前景。本文就应用于钛金属内植物表面的抗菌肽的抗菌机制、加载方式和应用现状等进行综述。 相似文献
106.
Amanda Bartkowiak Arkadiusz Zarzycki Slawomir Kac Marcin Perzanowski Marta Marszalek 《Materials》2020,13(22)
Nanotechnology is a very attractive tool for tailoring the surface of an orthopedic implant to optimize its interaction with the biological environment. Nanostructured interfaces are promising, especially for orthopedic applications. They can not only improve osseointegration between the implant and the living bone but also may be used as drug delivery platforms. The nanoporous structure can be used as a drug carrier to the surrounding tissue, with the intention to accelerate tissue–implant integration as well as to reduce and treat bacterial infections occurring after implantation. Titanium oxide nanotubes are promising for such applications; however, their brittle nature could be a significantly limiting factor. In this work, we modified the topography of commercially used titanium foil by the anodization process and hydrothermal treatment. As a result, we obtained a crystalline nanoporous u-shaped structure (US) of anodized titanium oxide with improved resistance to scratch compared to TiO2 nanotubes. The US titanium substrate was successfully modified with hydroxyapatite coating and investigated for bioactivity. Results showed high bioactivity in simulated body fluid (SBF) after two weeks of incubation. 相似文献
107.
A SiO2–Al2O3 glass composite coating was prepared on Ti60 alloy via air spraying slurry and then a suitable baking process. It was composed of potassium silicate glass, alumina and quartz powders. The high temperature oxidation performance of the alloy with and without coating was evaluated in static air at both 800 °C and 900 °C. The results show that catastrophic oxidation occurs for Ti60 bare alloy. It had a mass gain of about 2 mg/cm2 after oxidation at 800 °C and 17 mg/cm2 at 900 °C for 100 h. On the contrary, the oxidation resistance of alloy coated with composite coating was much improved with the mass gain about 0.36 mg/cm2 and 0.95 mg/cm2 at 800 °C and at 900 °C, respectively. The microstructure evolution of the composite coating and the alloy was analyzed by scanning electron microscope and electron probe microanalyzer. The effect of the composite coating on the oxidation performance of the alloy is discussed especially in terms of oxygen diffusion and interfacial reaction. 相似文献
108.
This paper presents the results of experimental research on the strength properties of porous structures with different degrees of density manufactured of Ti6Al4V titanium alloy by Laser Power Bed Fusion. In the experiment, samples with diamond structure of porosity: 34%, 50%, 73% and 81% were used, as well as samples with near-zero porosity. Monotonic tensile tests were carried out to determine the effective values of axial modulus of elasticity, ultimate tensile strength, offset yield strength, ultimate elongation and Poisson ratio for titanium alloys with different porosities. The paper also proposes relationships that can be easily used to estimate the strength and rigidity of a porous material manufactured by 3D printing. They were obtained by the approximation of two quotients. The first one refers to the relationship between the tensile strength of a material with a defined porosity to the strength of full-filled material. The second similarly determines the change in the value of the axial modulus of elasticity. The analysis of microscopic observations of fracture surfaces and also microtomography visualization of the material structure are also presented. 相似文献
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110.
Erica Dorigatti de Avila Rafael Scaf de Molon Carlos Eduardo Vergani Francisco de Assis Mollo Jr. Vehid Salih 《Materials》2014,7(5):3651-3662
The aim of this review was to investigate the relationship between biofilm and peri-implant disease, with an emphasis on the types of implant abutment surfaces. Individuals with periodontal disease typically have a large amount of pathogenic microorganisms in the periodontal pocket. If the individuals lose their teeth, these microorganisms remain viable inside the mouth and can directly influence peri-implant microbiota. Metal implants offer a suitable solution, but similarly, these remaining bacteria can adhere on abutment implant surfaces, induce peri-implantitis causing potential destruction of the alveolar bone near to the implant threads and cause the subsequent loss of the implant. Studies have demonstrated differences in biofilm formation on dental materials and these variations can be associated with both physical and chemical characteristics of the surfaces. In the case of partially edentulous patients affected by periodontal disease, the ideal type of implant abutments utilized should be one that adheres the least or negligible amounts of periodontopathogenic bacteria. Therefore, it is of clinically relevance to know how the bacteria behave on different types of surfaces in order to develop new materials and/or new types of treatment surfaces, which will reduce or inhibit adhesion of pathogenic microorganisms, and, thus, restrict the use of the abutments with indication propensity for bacterial adhesion. 相似文献