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Hydroxyapatite Coating (hydroxyapatite + coating)
Selected AbstractsElectrolytic Deposition of Hydroxyapatite Coating on CoNiCrMo SubstratesADVANCED ENGINEERING MATERIALS, Issue 1-2 2010Dong-Yang Lin Hydroxyapatite (HA) coating was fabricated on CoNiCrMo alloy by electrolytic deposition (ELD). Different kinds of uncharged substrates were placed close to the cathode separately during the ELD process. Both CoNiCrMo and uncharged substrates were covered with uniform HA coatings composed of hexagonal prism crystals after 60,min deposition. The pH value of the bulk solution changed hardly while the local pH had a sharp increase after ELD. The results demonstrate the local pH plays a crucial role in the ELD process. [source] Hydroxyapatite Coating on Thermally Oxidized Titanium SubstratesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2001Minkmas Vatanatham Titanium substrates were oxidized in oxygen or air at temperatures of 600°,800°C, then immersed in solutions of 2.0mM, 20.7mM CaCl2 and 1.2mM,12.4mM KH2PO4 for aging periods of 0.5,10 d. The titanium surface was successfully coated with hydroxyapatite (HAP) when the substrates were oxidized in oxygen gas at 610°C for 1 h and then aged in a solution of 2.00mM Ca2+ and 1.20mM PO43,. The Ca/P ratio of the surface coating increased toward its stoichiometric HAP value (return 10/6) as the aging time increased; the Ca/P ratio attained a value of 1.66 after 10 d. [source] Fibronectin Functionalized Hydroxyapatite Coatings: Improving Dermal Fibroblast Adhesion In Vitro and In Vivo,ADVANCED ENGINEERING MATERIALS, Issue 8 2010Catherine J. Pendegrass Skin-penetrating devices including intraosseous transcutaneous amputation prostheses (ITAP) and external fixator pins rely on a skin-implant seal to prevent infection. In this study, we assess the effectiveness of fibronectin (Fn) functionalized hydroxyapatite (HA) coatings for promoting dermal fibroblast and dermal tissue attachment and ingrowth in vitro and in vivo. By measuring the number of focal adhesions per unit cell area we have demonstrated that HA significantly promotes dermal fibroblast attachment compared with titanium alloy. Dermal fibroblast attachment is promoted further using Fn functionalized HA coatings incorporated into an implant design with 700,µm pores, which significantly increased dermal tissue ingrowth and attachment compared with non-functionalized HA and titanium alloy controls incorporating 500 or 1000,µm pores. We postulate that Fn functionalized HA coatings applied to transdermal implants may promote and sustain the skin-implant interface and assist in preventing infection long term. [source] Interaction of Osteoblasts with Macroporous Scaffolds Made of PLLA/PCL Blends Modified with Collagen and Hydroxyapatite,ADVANCED ENGINEERING MATERIALS, Issue 8 2009Halil Murat Aydin To mimic natural bone, a tissue engineering scaffold was developed that combines inorganic and organic components of natural bone, its pore diameter, and its interconnected structure. Collagen was coated onto a PLLA/PCL scaffold and hydroxyapatite particles were delivered throughout the polymer matrix much more easily than with other techniques thanks to the porosity-forming method of combining two porogens, namely, salt leaching and supercritical CO2 extraction. Compared with other coating techniques, this procedure can be performed readily and homogeneous 3D hydroxyapatite coating was achieved. [source] Hydrothermal crystallization of carbonate-containing hydroxyapatite coatings prepared by radiofrequency-magnetron sputtering methodJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007Satoshi Nakamura Abstract Carbonate-containing hydroxyapatite (HA) films were prepared by low-temperature hydrothermal annealing from carbonate-containing calcium phosphate amorphous coatings on titanium substrates. The biocompatibility of the carbonate-containing HA layers was estimated by in vitro tests using simulated body fluid (SBF). Precursory amorphous coatings were deposited with rf-magnetron sputtering apparatus, using calcium phosphate glass target in Ar/CO2 atmosphere. The carbonate-containing HA coatings were successfully formed by the annealing at above 130°C for 20 h. On the basis of SEM observation, about 2-,m thickness films coated rigidly were durable enough for the hydrothermal treatment. The coating layer was revealed to consist of single phase of PO4, and OH, partially carbonated HA by XRD and IR analyses. Overgrowing of bone-like apatite layers on the carbonate-containing HA surfaces in the SBF implied that the obtained films acquired a sufficient osteoconductivity, while it was still unclear that activity was enhanced, compared to pure HA coatings. The low-temperature hydrothermal annealing method was effective for preparation of rigid HA coatings on titanium as well as modification of their chemical compositions. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007 [source] | ||||||||||