Pub Date : 2015-07-17DOI: 10.1515/bglass-2015-0003
F. Baino, C. Vitale-Brovarone
Abstract In the last few years, optimal fixation of orthopaedic implants evolved to preserve host bone and enhance tissue integration by surface modifications, including the use of coatings with bioactive ceramics. In this work, we fabricated a novel bone-like porous bioactive glass-ceramic coating on curved alumina substrates; good joining between the two components was possible due to the interposition of a glass-derived dense interlayer. The mechanical properties of the porous glass-ceramic, which mimics the 3-D pore architecture of cancellous bone, are adequate for load-bearing applications (compressive strength of 19 MPa and fracture energy around 6.5×10−4 J mm−3, with a total porosity of 62 vol.%). In vitro bioactive behaviour was investigated by testing the samples in simulated body fluid and by evaluating the apatite formation on the surface and pore struts of the trabecular coating, which is a key precondition for in vivo osteointegration. The concepts disclosed in the present study could find interesting application in the context of orthopaedic implants, with particular reference to full-ceramic acetabular cups for hip joint prosthesis.
{"title":"Trabecular coating on curved alumina substrates using a novel bioactive and strong glass-ceramic","authors":"F. Baino, C. Vitale-Brovarone","doi":"10.1515/bglass-2015-0003","DOIUrl":"https://doi.org/10.1515/bglass-2015-0003","url":null,"abstract":"Abstract In the last few years, optimal fixation of orthopaedic implants evolved to preserve host bone and enhance tissue integration by surface modifications, including the use of coatings with bioactive ceramics. In this work, we fabricated a novel bone-like porous bioactive glass-ceramic coating on curved alumina substrates; good joining between the two components was possible due to the interposition of a glass-derived dense interlayer. The mechanical properties of the porous glass-ceramic, which mimics the 3-D pore architecture of cancellous bone, are adequate for load-bearing applications (compressive strength of 19 MPa and fracture energy around 6.5×10−4 J mm−3, with a total porosity of 62 vol.%). In vitro bioactive behaviour was investigated by testing the samples in simulated body fluid and by evaluating the apatite formation on the surface and pore struts of the trabecular coating, which is a key precondition for in vivo osteointegration. The concepts disclosed in the present study could find interesting application in the context of orthopaedic implants, with particular reference to full-ceramic acetabular cups for hip joint prosthesis.","PeriodicalId":37354,"journal":{"name":"Biomedical Glasses","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/bglass-2015-0003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67220863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-07-16DOI: 10.1515/bglass-2015-0002
Ashok Kumar, S. Murugavel
Abstract A new method of calcination for the sol-gel derived bioactive glass sample has been developed to produce superior textural and bioactive properties. Based on this method, mesoporous 67.4 SiO2-25 Na2O-5 CaO- 2.6 P2O5 (mol.%) bioactive glasses (MBGs) have been synthesized through acid assisted sol-gel technique followed by evaporation induced self-assembly (EISA) process, commonly used for obtaining bioactive glasses. Moreover, the use of microwave irradiation has been compared with that of conventional heat treatment for a particular quaternary composition,which has allowed the homogeneous spatial distribution of heat and to obtain smaller, uniform pore sizes with high surface area. The distinctions between the two methods of calcination have been observed in the structural, morphology and textural characteristics. The superior textural characteristics have allowed the rapid dissolution of MBGs followed by development of nanocrystalline hydroxycarbonate apatite (HCA) layer. In vitro bioactive analyses on both MBGs have revealed a rapid formation HCA layer with distinct behavior on the biomineralization process. The difference in the behavior of biomineralization process is attributed to the kinetics of supersaturation of the biological medium.
{"title":"Influence of textural properties on biomineralization behavior of mesoporous bioactive glasses","authors":"Ashok Kumar, S. Murugavel","doi":"10.1515/bglass-2015-0002","DOIUrl":"https://doi.org/10.1515/bglass-2015-0002","url":null,"abstract":"Abstract A new method of calcination for the sol-gel derived bioactive glass sample has been developed to produce superior textural and bioactive properties. Based on this method, mesoporous 67.4 SiO2-25 Na2O-5 CaO- 2.6 P2O5 (mol.%) bioactive glasses (MBGs) have been synthesized through acid assisted sol-gel technique followed by evaporation induced self-assembly (EISA) process, commonly used for obtaining bioactive glasses. Moreover, the use of microwave irradiation has been compared with that of conventional heat treatment for a particular quaternary composition,which has allowed the homogeneous spatial distribution of heat and to obtain smaller, uniform pore sizes with high surface area. The distinctions between the two methods of calcination have been observed in the structural, morphology and textural characteristics. The superior textural characteristics have allowed the rapid dissolution of MBGs followed by development of nanocrystalline hydroxycarbonate apatite (HCA) layer. In vitro bioactive analyses on both MBGs have revealed a rapid formation HCA layer with distinct behavior on the biomineralization process. The difference in the behavior of biomineralization process is attributed to the kinetics of supersaturation of the biological medium.","PeriodicalId":37354,"journal":{"name":"Biomedical Glasses","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/bglass-2015-0002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67220713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-09DOI: 10.1515/bglass-2015-0001
L. Hench
Abstract Historically the function of biomaterials was to replace diseased or damaged tissues. First generation biomaterials were selected to be as bio-inert as possible and thereby minimize formation of scar tissue at the interface with host tissues. Bioactive glasseswere discovered in 1969 and provided for the first time an alternative; strong, stable interfacial bonding of an implant with host tissues. In the 1980’s it was discovered that bioactive glasses could be used in particulae form to stimulate osteogenesiswhich thereby led to the concept of regeneration of tissues. This article summarizes the four eras of development of bioactive glasses that have led from concept of bioactivity to widespread clinical and commercial use, with emphasis on the first composition, 45S5 Bioglassr. The four eras are; A) Era of Discovery, B) Era of Clinical Application, C) Era of Tissue Regeneration, and D) Era of Innovation. Key scientific and technological questions answered for the first three eras are presented. Questions still to be answered for the fourth era are included to stimulate innovation in the field.
{"title":"Opening paper 2015- Some comments on Bioglass: Four Eras of Discovery and Development","authors":"L. Hench","doi":"10.1515/bglass-2015-0001","DOIUrl":"https://doi.org/10.1515/bglass-2015-0001","url":null,"abstract":"Abstract Historically the function of biomaterials was to replace diseased or damaged tissues. First generation biomaterials were selected to be as bio-inert as possible and thereby minimize formation of scar tissue at the interface with host tissues. Bioactive glasseswere discovered in 1969 and provided for the first time an alternative; strong, stable interfacial bonding of an implant with host tissues. In the 1980’s it was discovered that bioactive glasses could be used in particulae form to stimulate osteogenesiswhich thereby led to the concept of regeneration of tissues. This article summarizes the four eras of development of bioactive glasses that have led from concept of bioactivity to widespread clinical and commercial use, with emphasis on the first composition, 45S5 Bioglassr. The four eras are; A) Era of Discovery, B) Era of Clinical Application, C) Era of Tissue Regeneration, and D) Era of Innovation. Key scientific and technological questions answered for the first three eras are presented. Questions still to be answered for the fourth era are included to stimulate innovation in the field.","PeriodicalId":37354,"journal":{"name":"Biomedical Glasses","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/bglass-2015-0001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67220666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-30DOI: 10.1515/bglass-2015-0016
L. Placek, T. Keenan, F. Laffir, A. Coughlan, A. Wren
Abstract The structural effects of yttrium (Y) and cerium (Ce) are investigated when substituted for sodium (Na) in a 0.52SiO2–0.24SrO–(0.24−x)Na2O–xMO (where x = 0.08; MO = Y2O3 and CeO2) glass series. Network connectivity (NC) was calculated assuming both Y and Ce can act as a network modifier (NC = 2.2) or as a network former (NC up to 2.9). Thermal analysis showed an increase in glass transition temperature (Tg) with increasing Y and Ce content, Y causing the greater increase from the control (Con) at 493∘C to 8 mol% Y (HY) at 660∘C. Vickers hardness (HV) was not significantly different between glasses. 29Si Magic Angle Spinning-Nuclear Magnetic Resonance (MAS-NMR) did not show peak shift with addition of Y, however Ce produced peak broadening and a negative shift in ppm. The addition of 4 mol% Ce in the YCe and LCe glasses shifted the peak from Con at −81.3 ppm to −82.8 ppm and −82.7 ppm respectively; while the HCe glass produced a much broader peak and a shift to −84.8 ppm. High resolution X-ray Photoelectron Spectroscopy for the O 1s spectral line showed the ratio of bridging (BO) to non-bridging oxygens (NBO), BO:NBO,was altered,where Con had a ratio of 0.7, HY decreased to 0.4 and HCe to 0.5.
{"title":"Characterization of Y2O3 and CeO2 doped SiO2-SrO-Na2O glasses","authors":"L. Placek, T. Keenan, F. Laffir, A. Coughlan, A. Wren","doi":"10.1515/bglass-2015-0016","DOIUrl":"https://doi.org/10.1515/bglass-2015-0016","url":null,"abstract":"Abstract The structural effects of yttrium (Y) and cerium (Ce) are investigated when substituted for sodium (Na) in a 0.52SiO2–0.24SrO–(0.24−x)Na2O–xMO (where x = 0.08; MO = Y2O3 and CeO2) glass series. Network connectivity (NC) was calculated assuming both Y and Ce can act as a network modifier (NC = 2.2) or as a network former (NC up to 2.9). Thermal analysis showed an increase in glass transition temperature (Tg) with increasing Y and Ce content, Y causing the greater increase from the control (Con) at 493∘C to 8 mol% Y (HY) at 660∘C. Vickers hardness (HV) was not significantly different between glasses. 29Si Magic Angle Spinning-Nuclear Magnetic Resonance (MAS-NMR) did not show peak shift with addition of Y, however Ce produced peak broadening and a negative shift in ppm. The addition of 4 mol% Ce in the YCe and LCe glasses shifted the peak from Con at −81.3 ppm to −82.8 ppm and −82.7 ppm respectively; while the HCe glass produced a much broader peak and a shift to −84.8 ppm. High resolution X-ray Photoelectron Spectroscopy for the O 1s spectral line showed the ratio of bridging (BO) to non-bridging oxygens (NBO), BO:NBO,was altered,where Con had a ratio of 0.7, HY decreased to 0.4 and HCe to 0.5.","PeriodicalId":37354,"journal":{"name":"Biomedical Glasses","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/bglass-2015-0016","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67221724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}