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外科植入物用钛合金研究进展和标准化现状 总被引:5,自引:0,他引:5
介绍了外科植入物用钛的研究:(1)纯钛,Ti-6Al-4V合金;(2)Ti-6Al-7Nb合金;(3)新型β钛合金(Ti-13Nb-13Zr,Ti-12Mo-6Zr-2Fe,Ti-15Mo-2.8Nb-0.2Si合金);(4)Ti-Ni合金,概述了其研究进展,这些合金的性能特点,应用和标准化现状。 相似文献
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Mirja Fa?bender Susann Minkwitz Catrin Strobel Gerhard Schmidmaier Britt Wildemann 《International journal of molecular sciences》2014,15(5):8539-8552
The aim of the study was to investigate the effect of a sustained release of bone morphogenetic protein2 (BMP-2) incorporated in a polymeric implant coating on bone healing. In vitro analysis revealed a sustained, but incomplete BMP-2 release until Day 42. For the in vivo study, the rat tibia osteotomy was stabilized either with control or BMP-2 coated wires, and the healing progress was followed by micro computed tomography (μCT), biomechanical testing and histology at Days 10, 28, 42 and 84. MicroCT showed an accelerated formation of mineralized callus, as well as remodeling and an increase of mineralized/total callus volume (p = 0.021) at Day 42 in the BMP-2 group compared to the control. Histology revealed an increased callus mineralization at Days 42 and 84 (p = 0.006) with reduced cartilage at Day 84 (p = 0.004) in the BMP-2 group. Biomechanical stiffness was significantly higher in the BMP-2 group (p = 0.045) at Day 42. In summary, bone healing was enhanced after sustained BMP-2 application compared to the control. Using the same drug delivery system, but a burst release of BMP-2, a previous published study showed a similar positive effect on bone healing. Distinct differences in the healing outcome might be explained due to the different BMP release kinetics and dosages. However, further studies are necessary to adapt the optimal release profiles to physiological mechanisms. 相似文献
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Porous hydroxyapatite ocular implant was fabricated by a novel and simple method using hydroxyapatite powder synthesized in
the laboratory. The porosity and pore size of the implant were controlled to make it light in weight as well as suitable for
rapid vascularization after implantation. The implant was characterized by X-ray diffraction studies, infrared spectra and
chemical analysis for phase purity and chemical composition. The pore morphology and pore size distribution of the samples
were investigated by scanning electron microscope (SEM). Thereafter, efficacy of the implant was examined byin vivo study in dogs. Clinical, haematological and radiological studies indicated the suitability of the implant for replacement
of the lost eye of human patients. 相似文献
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M. V. Popa E. Vasilescu P. Drob I. Demetrescu B. Popescu D. Ionescu C. Vasilescu 《工业材料与腐蚀》2003,54(4):215-221
Long‐term monitoring (for 8000 exposure hours) of titanium and its implant alloys (Ti‐5Al‐4V, Ti‐6Al‐4Fe) interactions with Ringer's solutions of different pH‐values (2.5, 4.35, 6.98), simulating various conditions that can appear at the contact between implant and tissues was carried out in this paper. All data were statistics treated using Medcalc program. In vitro electrochemical behaviour of titanium and its alloys reveals their self‐passivation in Ringer's solutions. Monitoring of the open circuit potentials with time and pH have shown that the passive films on the implant materials studied were very stable for all tested periods. Interactions due to the non‐uniformity of the physiological electrolyte pH can not produce any form of local corrosion. The tested materials present low corrosion rates which attest their very good stability for 8000 exposure hours in simulated biological environment. Surface topography characterisation using atomic force microscopy (AFM) data, correlated with the electrochemical parameters, were arguments for the stability of the samples in studied bioliquids. 相似文献
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就新旧混凝土粘结界面破坏机理进行了探讨,从界面处理方式、粗糙度评定、界面剂选择、粘结方位、机械栓及植筋等方面对影响新旧混凝土粘结界面力学性能的因素进行了综述。 相似文献
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Hongbo Wei Lingzhou Zhao Bangdao Chen Shizhu Bai Yimin Zhao 《International journal of molecular sciences》2014,15(7):12998-13009
Fibroblasts, which play an important role in biological seal formation and maintenance, determine the long-term success of percutaneous implants. In this study, well-defined microporous structures with micropore diameters of 10–60 µm were fabricated by microelectromechanical systems and their influence on the fibroblast functionalities was observed. The results show that the microporous structures with micropore diameters of 10–60 µm did not influence the initial adherent fibroblast number; however, those with diameters of 40 and 50 µm improved the spread, actin stress fiber organization, proliferation and fibronectin secretion of the fibroblasts. The microporous structures with micropore diameters of 40–50 µm may be promising for application in the percutaneous part of an implant. 相似文献