The Experts below are selected from a list of 18294 Experts worldwide ranked by ideXlab platform
Akihisa Inoue - One of the best experts on this subject based on the ideXlab platform.
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effect of spraying condition on property of zr based metallic Glass coating by gas tunnel type plasma spraying
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2010Co-Authors: Akira Kobayashi, Toshio Kuroda, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high strength and high corrosion resistance. However, as metallic Glass is expensive, a composite material is preferred for better cost performance. Thermal spraying is one of the potential candidates to produce such metallic Glass composites. Gas tunnel type plasma spraying is useful in obtaining high quality ceramic Coatings because it can easily control the condition of spraying powder. In this study, Zr-based metallic Glass (Zr55–Cu30–Al10–Ni5) Coatings were produced by gas tunnel type plasma spraying, and the effect of spraying conditions on the properties of Zr-based metallic Glass coating was investigated. Dense Zr-based metallic Glass Coatings of more than 200 μm in thickness were prepared with a Vickers hardness of about Hv = 550 at a plasma current of 250 A, and the amorphous phase of this metallic Glass coating appeared to remain in good condition.
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mechanical properties and microstructure of plasma sprayed ni based metallic Glass coating
NEW TREND IN APPLIED PLASMA SCIENCE AND TECHNOLOGY: The Seventh International Symposium on Applied Plasma Science, 2010Co-Authors: Akira Kobayashi, Toshio Kuroda, Hisamichi Kimura, Akihisa InoueAbstract:Various developmental research works on the metallic Glass have been conducted in order to broaden its application field. Thermal spraying method is one of the potential techniques to enhance the excellent properties such as high toughness and corrosion resistance of the metallic Glass material. The gas tunnel type plasma spraying is useful to obtain high quality ceramic Coatings such as Al2O3 and ZrO2 Coatings. In this study, the Ni‐based metallic Glass Coatings were produced by the gas tunnel type plasma spraying under various experimental conditions, and their microstructure and mechanical properties were investigated. At the plasma current of 200–300 A, the Ni‐based metallic Glass Coatings of more than 200 μm in thickness were formed densely with Vickers hardness of about Hv = 600.
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mechanical property of fe base metallic Glass coating formed by gas tunnel type plasma spraying
Surface & Coatings Technology, 2008Co-Authors: Akira Kobayashi, Shoji Yano, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high toughness and corrosion resistance. Therefore it is one of the most attractive materials, and many researchers have conducted various developmental research works. However, the metallic Glass material is expensive and a composite material is preferred for the industrial application. Thermal spraying method is one of potential candidates to produce metallic Glass composites. The gas tunnel type plasma system, which has high energy density and efficiency, is useful for smart plasma processing to obtain high quality ceramic Coatings such as alumina (Al 2 O 3 ) and zirconia (ZrO 2 ) Coatings. Also, the gas tunnel type plasma spraying can produce metallic Glass Coatings. In this study, the Fe-base metallic Glass Coatings were formed on the stainless-steel substrate by the gas tunnel type plasma spraying, and the microstructure and mechanical property were investigated. The Fe-base metallic Glass Coatings of about 200 μm in thickness were dense with a Vickers hardness of about Hv = 1100 at plasma current of 300 A. The abrasive wear resistance of Fe-base metallic Glass coating was higher than the SUS substrate.
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Fe-based metallic Glass Coatings produced by smart plasma spraying process
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2008Co-Authors: Akira Kobayashi, Shoji Yano, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high toughness and corrosion resistance. Therefore it is one of the most attractive materials, and many researchers have conducted various developmental research works. However, the metallic Glass material is expensive and a composite material is preferred for the industrial application. Thermal spraying method is a potential candidate to produce metallic Glass composites. The gas tunnel type plasma system is useful for smart plasma processing to obtain high quality ceramic Coatings such as alumina (Al2O3) and zirconia (ZrO2) Coatings. Also, the gas tunnel type plasma spraying can produce metallic Glass Coatings. In this study, the Fe-based metallic Glass Coatings were produced by gas tunnel type plasma spraying, and the microstructure and some properties were investigated. The amorphous phase of this metallic Glass coating was confirmed by the XRD method. The Fe-based metallic Glass Coatings of about 200 μm in thickness were dense with a Vickers hardness of about Hv = 1100 at plasma current of 300 A.
Antoni P Tomsia - One of the best experts on this subject based on the ideXlab platform.
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soda lime Glass coating containing silver nanoparticles on ti 6al 4v alloy
Journal of The European Ceramic Society, 2012Co-Authors: Leticia Estebantejeda, Eduardo Saiz, Antoni P Tomsia, Belen Cabal, Francisco Malpartida, Roberto Lopezpiriz, Ramon Torrecillas, J S MoyaAbstract:Abstract The prevention and treatment of post-surgical infections is an ongoing concern. Post-surgical infections often cannot be treated with commercially available antibiotic-loaded bone cement as because higher doses of antibiotics are required. We describe here an approach to prevent implant infection through the use of Glass Coatings combined with silver nanoparticles deposited by sedimentation and heat-treated at 980 °C on titanium alloys. Silver is nontoxic to the human tissue and has been used as an anti-infective for centuries. The Glass/silver Coatings are composed of a soda-lime Glassy matrix containing silver nanoparticles ranging from 2.6 to 20 wt.%. Optimum firing conditions have been determined for the fabrication of Coatings that adhere well to the metal implant. These final Coatings do not crack or delaminate. The biocidal activity of these Coatings was also investigated. Coatings containing 20 wt.% of silver nanoparticles exhibited excellent biocidal activity (log η > 5) against Gram+, Gram− bacteria, and yeast after 24 h.
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bioactive Glass Coatings affect the behavior of osteoblast like cells
Acta Biomaterialia, 2007Co-Authors: Silvia Foppiano, Eduardo Saiz, Sally J. Marshall, G W Marshall, Antoni P TomsiaAbstract:Abstract Functionally graded Coatings (FGCs) of bioactive Glass on titanium alloy (Ti6Al4V) were fabricated by the enameling technique. These innovative Coatings may be an alternative to plasma-sprayed, hydroxyapatite-coated implants. Previously we determined that a preconditioning treatment in simulated body fluid (SBF) helped to stabilize FGCs [Foppiano S et al. Acta Biomater 2006;2(2):133–42]. The primary goal of this work was to assess the in vitro cytocompatibility of preconditioned FGCs with MC3T3-E1.4 mouse pre-osteoblastic cells. We evaluated cell adhesion, proliferation and mineralization on FGCs in comparison to uncoated Ti6Al4V and tissue culture polystyrene (TCPS). No difference in cell adhesion was identified, whereas proliferation was significantly different on all materials, being highest on FGCs followed by TCPS and Ti6Al4V. Qualitative and quantitative mineralization assays indicated that mineralization occurred on all materials. The amount of inorganic phosphate released by the mineralizing layers was significantly different, being highest on TCPS, followed by FGC and uncoated Ti6Al4V. The secondary objective of this work was to assess the ability of the FGCs to affect gene expression, indirectly, by means of their dissolution products, which was assessed by real-time reverse-transcription polymerase chain reaction. The FGC dissolution products induced a 2-fold increase in the expression of Runx-2, and a 20% decrease in the expression of collagen type 1 with respect to TCPS extract. These genes are regulators of osteoblast differentiation and mineralization, respectively. The findings of this study indicate that preconditioned FGCs are cytocompatible and suggest that future work may allow composition changes to induce preferred gene expression.
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biomimetic bonelike composites and novel bioactive Glass Coatings
Lawrence Berkeley National Laboratory, 2005Co-Authors: Antoni P Tomsia, Eduardo Saiz, Jie Song, Carolyn R BertozziAbstract:Biomimetic Bonelike Composites and Novel Bioactive Glass Coatings A. P. Tomsia, # E. Saiz, # J. Song, # C. Bertozzi #,† Materials Sciences Division Lawrence Berkeley National Laboratory Berkeley, CA 94720, USA Departments of Chemistry, Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, California 94720, U.S.A. Abstract Metallic orthopaedic implants have been successfully used for decades but they have serious shortcomings related to their osseointegration and the fact that their mechanical properties do not match those of bone. This paper reviews recent advances in the fabrication of novel Coatings to improve implant osseointegration and in the development of a new generation of hybrid organic-inorganic implant materials specifically designed for orthopaedic applications Introduction The number of orthopedic surgeries performed worldwide is growing 10 to 12% annually. [1] As these procedures become more popular, and patients desire to lead more active lives, these rates are expected to increase. An estimated 11 million people in the U.S. have at least one medical-device implant and more than $50 billion are spent annually on reconstructive devices. [2] In 2003 alone, more than 700,000 dental implant procedures were performed in the U.S., and more than 1.3 million in Europe; [3] sales in 2003 for implants and devices were $8.7 billion and are expected to rise at an annual growth rate of 12.5% and reach $17.9 billion by 2009. [1] Current commercial implants are fabricated using materials typically developed for other engineering applications, and their osseointegration and long-term stability are still a source of concern. The National Center for Health Statistics reports that nearly 15% of the hip replacement surgeries performed in 2002 were to revise original replacements, [4] and this number is likely to increase as younger people undergo these procedures. These numbers emphasize the need for a coordinated research effort to provide patients and doctors with better and more durable implants. A short- to medium-term solution is the modification of implant surfaces to enhance bonding to bone. In the long term, new implant materials—materials that will match the mechanical properties of bone and be actively integrated and remodeled by the body—should be developed. This paper reviews some of the recent efforts in the development of bioactive Glass Coatings to enhance the osseointegration of metallic and ceramic implants, and the most recent research in the field of organic- inorganic hybrid composites specifically designed for bone replacement.
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biomimetic bonelike composites and novel bioactive Glass Coatings
Advanced Engineering Materials, 2005Co-Authors: Antoni P Tomsia, Eduardo Saiz, Jie Song, Carolyn R BertozziAbstract:Metallic orthopaedic implants have been successfully used for decades but they have serious shortcomings related to their osseointegration and the fact that their mechanical properties do not match those of bone. This paper reviews recent advances in the fabrication of novel Coatings to improve implant osseointegration and in the development of a new generation of hybrid organic-inorganic implant materials specifically designed for orthopaedic applications.
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bioactive Glass Coatings for orthopedic metallic implants
Journal of The European Ceramic Society, 2003Co-Authors: Sonia Lopezesteban, Eduardo Saiz, Sigheru Fujino, Katsuaki Suganuma, Antoni P TomsiaAbstract:The objective of this work is to develop bioactive Glass Coatings for metallic orthopedic implants. A new family of Glasses in the SiO2-Na2O-K2O-CaO-MgO-P2O5 system has been synthesized and characterized. The Glass properties (thermal expansion, softening and transformation temperatures, density and hardness) are in line with the predictions of established empirical models. The optimized firing conditions to fabricate Coatings on Ti-based and Co-Cr alloys have been determined and related to the Glass properties and the interfacial reactions. Excellent adhesion to alloys has been achieved through the formation of 100-200 nm thick interfacial layers (Ti5Si3 on Ti-based alloys and CrOx on Co-Cr). Finally, Glass Coatings, approximately 100 mu m thick, have been fabricated onto commercial Ti alloy-based dental implants.
Akira Kobayashi - One of the best experts on this subject based on the ideXlab platform.
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effect of spraying condition on property of zr based metallic Glass coating by gas tunnel type plasma spraying
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2010Co-Authors: Akira Kobayashi, Toshio Kuroda, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high strength and high corrosion resistance. However, as metallic Glass is expensive, a composite material is preferred for better cost performance. Thermal spraying is one of the potential candidates to produce such metallic Glass composites. Gas tunnel type plasma spraying is useful in obtaining high quality ceramic Coatings because it can easily control the condition of spraying powder. In this study, Zr-based metallic Glass (Zr55–Cu30–Al10–Ni5) Coatings were produced by gas tunnel type plasma spraying, and the effect of spraying conditions on the properties of Zr-based metallic Glass coating was investigated. Dense Zr-based metallic Glass Coatings of more than 200 μm in thickness were prepared with a Vickers hardness of about Hv = 550 at a plasma current of 250 A, and the amorphous phase of this metallic Glass coating appeared to remain in good condition.
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mechanical properties and microstructure of plasma sprayed ni based metallic Glass coating
NEW TREND IN APPLIED PLASMA SCIENCE AND TECHNOLOGY: The Seventh International Symposium on Applied Plasma Science, 2010Co-Authors: Akira Kobayashi, Toshio Kuroda, Hisamichi Kimura, Akihisa InoueAbstract:Various developmental research works on the metallic Glass have been conducted in order to broaden its application field. Thermal spraying method is one of the potential techniques to enhance the excellent properties such as high toughness and corrosion resistance of the metallic Glass material. The gas tunnel type plasma spraying is useful to obtain high quality ceramic Coatings such as Al2O3 and ZrO2 Coatings. In this study, the Ni‐based metallic Glass Coatings were produced by the gas tunnel type plasma spraying under various experimental conditions, and their microstructure and mechanical properties were investigated. At the plasma current of 200–300 A, the Ni‐based metallic Glass Coatings of more than 200 μm in thickness were formed densely with Vickers hardness of about Hv = 600.
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mechanical property of fe base metallic Glass coating formed by gas tunnel type plasma spraying
Surface & Coatings Technology, 2008Co-Authors: Akira Kobayashi, Shoji Yano, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high toughness and corrosion resistance. Therefore it is one of the most attractive materials, and many researchers have conducted various developmental research works. However, the metallic Glass material is expensive and a composite material is preferred for the industrial application. Thermal spraying method is one of potential candidates to produce metallic Glass composites. The gas tunnel type plasma system, which has high energy density and efficiency, is useful for smart plasma processing to obtain high quality ceramic Coatings such as alumina (Al 2 O 3 ) and zirconia (ZrO 2 ) Coatings. Also, the gas tunnel type plasma spraying can produce metallic Glass Coatings. In this study, the Fe-base metallic Glass Coatings were formed on the stainless-steel substrate by the gas tunnel type plasma spraying, and the microstructure and mechanical property were investigated. The Fe-base metallic Glass Coatings of about 200 μm in thickness were dense with a Vickers hardness of about Hv = 1100 at plasma current of 300 A. The abrasive wear resistance of Fe-base metallic Glass coating was higher than the SUS substrate.
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Fe-based metallic Glass Coatings produced by smart plasma spraying process
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2008Co-Authors: Akira Kobayashi, Shoji Yano, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high toughness and corrosion resistance. Therefore it is one of the most attractive materials, and many researchers have conducted various developmental research works. However, the metallic Glass material is expensive and a composite material is preferred for the industrial application. Thermal spraying method is a potential candidate to produce metallic Glass composites. The gas tunnel type plasma system is useful for smart plasma processing to obtain high quality ceramic Coatings such as alumina (Al2O3) and zirconia (ZrO2) Coatings. Also, the gas tunnel type plasma spraying can produce metallic Glass Coatings. In this study, the Fe-based metallic Glass Coatings were produced by gas tunnel type plasma spraying, and the microstructure and some properties were investigated. The amorphous phase of this metallic Glass coating was confirmed by the XRD method. The Fe-based metallic Glass Coatings of about 200 μm in thickness were dense with a Vickers hardness of about Hv = 1100 at plasma current of 300 A.
Hisamichi Kimura - One of the best experts on this subject based on the ideXlab platform.
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effect of spraying condition on property of zr based metallic Glass coating by gas tunnel type plasma spraying
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2010Co-Authors: Akira Kobayashi, Toshio Kuroda, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high strength and high corrosion resistance. However, as metallic Glass is expensive, a composite material is preferred for better cost performance. Thermal spraying is one of the potential candidates to produce such metallic Glass composites. Gas tunnel type plasma spraying is useful in obtaining high quality ceramic Coatings because it can easily control the condition of spraying powder. In this study, Zr-based metallic Glass (Zr55–Cu30–Al10–Ni5) Coatings were produced by gas tunnel type plasma spraying, and the effect of spraying conditions on the properties of Zr-based metallic Glass coating was investigated. Dense Zr-based metallic Glass Coatings of more than 200 μm in thickness were prepared with a Vickers hardness of about Hv = 550 at a plasma current of 250 A, and the amorphous phase of this metallic Glass coating appeared to remain in good condition.
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mechanical properties and microstructure of plasma sprayed ni based metallic Glass coating
NEW TREND IN APPLIED PLASMA SCIENCE AND TECHNOLOGY: The Seventh International Symposium on Applied Plasma Science, 2010Co-Authors: Akira Kobayashi, Toshio Kuroda, Hisamichi Kimura, Akihisa InoueAbstract:Various developmental research works on the metallic Glass have been conducted in order to broaden its application field. Thermal spraying method is one of the potential techniques to enhance the excellent properties such as high toughness and corrosion resistance of the metallic Glass material. The gas tunnel type plasma spraying is useful to obtain high quality ceramic Coatings such as Al2O3 and ZrO2 Coatings. In this study, the Ni‐based metallic Glass Coatings were produced by the gas tunnel type plasma spraying under various experimental conditions, and their microstructure and mechanical properties were investigated. At the plasma current of 200–300 A, the Ni‐based metallic Glass Coatings of more than 200 μm in thickness were formed densely with Vickers hardness of about Hv = 600.
-
mechanical property of fe base metallic Glass coating formed by gas tunnel type plasma spraying
Surface & Coatings Technology, 2008Co-Authors: Akira Kobayashi, Shoji Yano, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high toughness and corrosion resistance. Therefore it is one of the most attractive materials, and many researchers have conducted various developmental research works. However, the metallic Glass material is expensive and a composite material is preferred for the industrial application. Thermal spraying method is one of potential candidates to produce metallic Glass composites. The gas tunnel type plasma system, which has high energy density and efficiency, is useful for smart plasma processing to obtain high quality ceramic Coatings such as alumina (Al 2 O 3 ) and zirconia (ZrO 2 ) Coatings. Also, the gas tunnel type plasma spraying can produce metallic Glass Coatings. In this study, the Fe-base metallic Glass Coatings were formed on the stainless-steel substrate by the gas tunnel type plasma spraying, and the microstructure and mechanical property were investigated. The Fe-base metallic Glass Coatings of about 200 μm in thickness were dense with a Vickers hardness of about Hv = 1100 at plasma current of 300 A. The abrasive wear resistance of Fe-base metallic Glass coating was higher than the SUS substrate.
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Fe-based metallic Glass Coatings produced by smart plasma spraying process
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2008Co-Authors: Akira Kobayashi, Shoji Yano, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high toughness and corrosion resistance. Therefore it is one of the most attractive materials, and many researchers have conducted various developmental research works. However, the metallic Glass material is expensive and a composite material is preferred for the industrial application. Thermal spraying method is a potential candidate to produce metallic Glass composites. The gas tunnel type plasma system is useful for smart plasma processing to obtain high quality ceramic Coatings such as alumina (Al2O3) and zirconia (ZrO2) Coatings. Also, the gas tunnel type plasma spraying can produce metallic Glass Coatings. In this study, the Fe-based metallic Glass Coatings were produced by gas tunnel type plasma spraying, and the microstructure and some properties were investigated. The amorphous phase of this metallic Glass coating was confirmed by the XRD method. The Fe-based metallic Glass Coatings of about 200 μm in thickness were dense with a Vickers hardness of about Hv = 1100 at plasma current of 300 A.
Eduardo Saiz - One of the best experts on this subject based on the ideXlab platform.
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soda lime Glass coating containing silver nanoparticles on ti 6al 4v alloy
Journal of The European Ceramic Society, 2012Co-Authors: Leticia Estebantejeda, Eduardo Saiz, Antoni P Tomsia, Belen Cabal, Francisco Malpartida, Roberto Lopezpiriz, Ramon Torrecillas, J S MoyaAbstract:Abstract The prevention and treatment of post-surgical infections is an ongoing concern. Post-surgical infections often cannot be treated with commercially available antibiotic-loaded bone cement as because higher doses of antibiotics are required. We describe here an approach to prevent implant infection through the use of Glass Coatings combined with silver nanoparticles deposited by sedimentation and heat-treated at 980 °C on titanium alloys. Silver is nontoxic to the human tissue and has been used as an anti-infective for centuries. The Glass/silver Coatings are composed of a soda-lime Glassy matrix containing silver nanoparticles ranging from 2.6 to 20 wt.%. Optimum firing conditions have been determined for the fabrication of Coatings that adhere well to the metal implant. These final Coatings do not crack or delaminate. The biocidal activity of these Coatings was also investigated. Coatings containing 20 wt.% of silver nanoparticles exhibited excellent biocidal activity (log η > 5) against Gram+, Gram− bacteria, and yeast after 24 h.
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bioactive Glass Coatings affect the behavior of osteoblast like cells
Acta Biomaterialia, 2007Co-Authors: Silvia Foppiano, Eduardo Saiz, Sally J. Marshall, G W Marshall, Antoni P TomsiaAbstract:Abstract Functionally graded Coatings (FGCs) of bioactive Glass on titanium alloy (Ti6Al4V) were fabricated by the enameling technique. These innovative Coatings may be an alternative to plasma-sprayed, hydroxyapatite-coated implants. Previously we determined that a preconditioning treatment in simulated body fluid (SBF) helped to stabilize FGCs [Foppiano S et al. Acta Biomater 2006;2(2):133–42]. The primary goal of this work was to assess the in vitro cytocompatibility of preconditioned FGCs with MC3T3-E1.4 mouse pre-osteoblastic cells. We evaluated cell adhesion, proliferation and mineralization on FGCs in comparison to uncoated Ti6Al4V and tissue culture polystyrene (TCPS). No difference in cell adhesion was identified, whereas proliferation was significantly different on all materials, being highest on FGCs followed by TCPS and Ti6Al4V. Qualitative and quantitative mineralization assays indicated that mineralization occurred on all materials. The amount of inorganic phosphate released by the mineralizing layers was significantly different, being highest on TCPS, followed by FGC and uncoated Ti6Al4V. The secondary objective of this work was to assess the ability of the FGCs to affect gene expression, indirectly, by means of their dissolution products, which was assessed by real-time reverse-transcription polymerase chain reaction. The FGC dissolution products induced a 2-fold increase in the expression of Runx-2, and a 20% decrease in the expression of collagen type 1 with respect to TCPS extract. These genes are regulators of osteoblast differentiation and mineralization, respectively. The findings of this study indicate that preconditioned FGCs are cytocompatible and suggest that future work may allow composition changes to induce preferred gene expression.
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biomimetic bonelike composites and novel bioactive Glass Coatings
Lawrence Berkeley National Laboratory, 2005Co-Authors: Antoni P Tomsia, Eduardo Saiz, Jie Song, Carolyn R BertozziAbstract:Biomimetic Bonelike Composites and Novel Bioactive Glass Coatings A. P. Tomsia, # E. Saiz, # J. Song, # C. Bertozzi #,† Materials Sciences Division Lawrence Berkeley National Laboratory Berkeley, CA 94720, USA Departments of Chemistry, Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, California 94720, U.S.A. Abstract Metallic orthopaedic implants have been successfully used for decades but they have serious shortcomings related to their osseointegration and the fact that their mechanical properties do not match those of bone. This paper reviews recent advances in the fabrication of novel Coatings to improve implant osseointegration and in the development of a new generation of hybrid organic-inorganic implant materials specifically designed for orthopaedic applications Introduction The number of orthopedic surgeries performed worldwide is growing 10 to 12% annually. [1] As these procedures become more popular, and patients desire to lead more active lives, these rates are expected to increase. An estimated 11 million people in the U.S. have at least one medical-device implant and more than $50 billion are spent annually on reconstructive devices. [2] In 2003 alone, more than 700,000 dental implant procedures were performed in the U.S., and more than 1.3 million in Europe; [3] sales in 2003 for implants and devices were $8.7 billion and are expected to rise at an annual growth rate of 12.5% and reach $17.9 billion by 2009. [1] Current commercial implants are fabricated using materials typically developed for other engineering applications, and their osseointegration and long-term stability are still a source of concern. The National Center for Health Statistics reports that nearly 15% of the hip replacement surgeries performed in 2002 were to revise original replacements, [4] and this number is likely to increase as younger people undergo these procedures. These numbers emphasize the need for a coordinated research effort to provide patients and doctors with better and more durable implants. A short- to medium-term solution is the modification of implant surfaces to enhance bonding to bone. In the long term, new implant materials—materials that will match the mechanical properties of bone and be actively integrated and remodeled by the body—should be developed. This paper reviews some of the recent efforts in the development of bioactive Glass Coatings to enhance the osseointegration of metallic and ceramic implants, and the most recent research in the field of organic- inorganic hybrid composites specifically designed for bone replacement.
-
biomimetic bonelike composites and novel bioactive Glass Coatings
Advanced Engineering Materials, 2005Co-Authors: Antoni P Tomsia, Eduardo Saiz, Jie Song, Carolyn R BertozziAbstract:Metallic orthopaedic implants have been successfully used for decades but they have serious shortcomings related to their osseointegration and the fact that their mechanical properties do not match those of bone. This paper reviews recent advances in the fabrication of novel Coatings to improve implant osseointegration and in the development of a new generation of hybrid organic-inorganic implant materials specifically designed for orthopaedic applications.
-
bioactive Glass Coatings for orthopedic metallic implants
Journal of The European Ceramic Society, 2003Co-Authors: Sonia Lopezesteban, Eduardo Saiz, Sigheru Fujino, Katsuaki Suganuma, Antoni P TomsiaAbstract:The objective of this work is to develop bioactive Glass Coatings for metallic orthopedic implants. A new family of Glasses in the SiO2-Na2O-K2O-CaO-MgO-P2O5 system has been synthesized and characterized. The Glass properties (thermal expansion, softening and transformation temperatures, density and hardness) are in line with the predictions of established empirical models. The optimized firing conditions to fabricate Coatings on Ti-based and Co-Cr alloys have been determined and related to the Glass properties and the interfacial reactions. Excellent adhesion to alloys has been achieved through the formation of 100-200 nm thick interfacial layers (Ti5Si3 on Ti-based alloys and CrOx on Co-Cr). Finally, Glass Coatings, approximately 100 mu m thick, have been fabricated onto commercial Ti alloy-based dental implants.