Titanium implants are extensively used in orthopaedics and odontoiatrics due to their outstanding mechanical characteristics and acceptable biocompatibility. However, metal implant/native bone tissue interface does not provide suitable osseointegration and, therefore, it should be properly treated and/or coated by bioactive materials, in order to optimise the long-term characteristics of bone implants and to create an improved cellular response. Among the possible coating materials, substituted hydroxyapatite and glass-ceramics are used. Hydroxyapatite based coating materials are more traditional for bone implant applications, since their composition is close to the mineral part of the host tissue. However, the focus point is to shift to bioactive glass compositions for a certain part of applications, since the ability of bioactive glasses to continuously exchange ions with physiological liquids and to release appropriate trace elements stimulates cellular response, aimed to activate genes responsible for osteogenesis and bone tissue regeneration. In this work, Pulsed Laser Deposition technique was used for films preparation. Structural and morphological properties of the deposited coatings were investigated by X-ray Diffraction, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy (SEM-EDS) and Atomic Force Microscopy. In addition, Vickers microhardness of the film-substrate composite system was measured, and the intrinsic hardness of films was properly separated from the composite hardness, using the "law-of-mixtures" approach and taking into account the indentation size effect. In vitro bioactivity tests in alpha-MEM were performed. Furthermore, the biocompatibility and cell-friendly characteristics of the prepared coatings were tested. For this purpose, metabolic activity and proliferation of the human colon carcinoma CaCo-2 cells and the human amniotic mesenchymal stromal cells (hAMSC) were investigated. The results of the present study suggest that novel coatings may be particularly relevant for new strategies in bone tissue regeneration and replacement, ensuring necessary structural, chemical, morphological and mechanical characteristics and improving the osseointegration of bone implants. References [1] J.V. Rau, R. Teghil, M. Fosca, A. De Bonis, I. Cacciotti, A. Bianco, V. Rossi Albertini, R. Caminiti, A. Ravaglioli, Bioactive glass-ceramic coatings prepared by pulsed laser deposition from RKKP targets (sol-gel vs melt-processing route), Mater. Res. Bull. 47 (2012) 1130-1137. [2] J.V. Rau, I. Cacciotti, S. Laureti, M. Fosca, G. Varvaro, A. Latini, Bioactive, Nanostructured Si-substituted Hydroxyapatite Coatings on Titanium Prepared by Pulsed Laser Deposition, J. Biomed. Mater. Res.: Part B - Appl. Biomat. (in press, 2015) doi: 10.1002/jbm.b.33344 [3] M. Ledda, A. De Bonis, F.R. Bertani, I. Cacciotti, R. Teghil, M.G. Lolli, A. Ravaglioli, A. Lisi, J.V. Rau, Interdisciplinary approach to cell-biomaterial interactions: biocompatibility and cell friendly characteristics of RKKP glass-ceramic coatings on titanium, Biomed. Mater. (in press, 2015).
Bioactive substituted hydroxyapatite and glass-ceramic coatings for bone implant applications
JV Rau;M Fosca;
2015
Abstract
Titanium implants are extensively used in orthopaedics and odontoiatrics due to their outstanding mechanical characteristics and acceptable biocompatibility. However, metal implant/native bone tissue interface does not provide suitable osseointegration and, therefore, it should be properly treated and/or coated by bioactive materials, in order to optimise the long-term characteristics of bone implants and to create an improved cellular response. Among the possible coating materials, substituted hydroxyapatite and glass-ceramics are used. Hydroxyapatite based coating materials are more traditional for bone implant applications, since their composition is close to the mineral part of the host tissue. However, the focus point is to shift to bioactive glass compositions for a certain part of applications, since the ability of bioactive glasses to continuously exchange ions with physiological liquids and to release appropriate trace elements stimulates cellular response, aimed to activate genes responsible for osteogenesis and bone tissue regeneration. In this work, Pulsed Laser Deposition technique was used for films preparation. Structural and morphological properties of the deposited coatings were investigated by X-ray Diffraction, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy (SEM-EDS) and Atomic Force Microscopy. In addition, Vickers microhardness of the film-substrate composite system was measured, and the intrinsic hardness of films was properly separated from the composite hardness, using the "law-of-mixtures" approach and taking into account the indentation size effect. In vitro bioactivity tests in alpha-MEM were performed. Furthermore, the biocompatibility and cell-friendly characteristics of the prepared coatings were tested. For this purpose, metabolic activity and proliferation of the human colon carcinoma CaCo-2 cells and the human amniotic mesenchymal stromal cells (hAMSC) were investigated. The results of the present study suggest that novel coatings may be particularly relevant for new strategies in bone tissue regeneration and replacement, ensuring necessary structural, chemical, morphological and mechanical characteristics and improving the osseointegration of bone implants. References [1] J.V. Rau, R. Teghil, M. Fosca, A. De Bonis, I. Cacciotti, A. Bianco, V. Rossi Albertini, R. Caminiti, A. Ravaglioli, Bioactive glass-ceramic coatings prepared by pulsed laser deposition from RKKP targets (sol-gel vs melt-processing route), Mater. Res. Bull. 47 (2012) 1130-1137. [2] J.V. Rau, I. Cacciotti, S. Laureti, M. Fosca, G. Varvaro, A. Latini, Bioactive, Nanostructured Si-substituted Hydroxyapatite Coatings on Titanium Prepared by Pulsed Laser Deposition, J. Biomed. Mater. Res.: Part B - Appl. Biomat. (in press, 2015) doi: 10.1002/jbm.b.33344 [3] M. Ledda, A. De Bonis, F.R. Bertani, I. Cacciotti, R. Teghil, M.G. Lolli, A. Ravaglioli, A. Lisi, J.V. Rau, Interdisciplinary approach to cell-biomaterial interactions: biocompatibility and cell friendly characteristics of RKKP glass-ceramic coatings on titanium, Biomed. Mater. (in press, 2015).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
