Author: Deejay MehtaPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
An in Vitro Investigation Into the Surface Modification of Titanium and Its Effect on Bond Strength to Porcelain
Author: Deejay MehtaSurface Modification of Titanium for Enhancing Titanium-porcelain Bond Strength
Author: Che-Shun WangInvestigation on the Surface Modification of Titanium Based Alloys for Improved Bioactivity
Author: Mohammad Mohsin HossainPublisher:
ISBN:
Category : Titanium alloys
Languages : en
Pages : 538
Book Description
Titanium-based engineering materials are currently considered to be the best artificial implant materials because of their good mechanical strength, resistance to corrosion, and their nontoxic compatibility with the stable oxide, TiO2. Ti6Al4V alloy is biologically inert, showing limited interaction with human tissue to their native oxide surface, which generally results in mechanical fixation. If the material is able to interact directly with tissue through chemical bonding, thus leading to a bioactive fixation, this will make a better and stronger implant for the promotion of cell attachment and migration and bone growth. Surface modification can improve the properties of surface oxide, leading to the formation of a stable oxide layer on the alloy's surface, and thus resulting in greater bioactivity. Surface modification is performed through surface chemical treatments, coatings deposition and chemical and thermal oxidation at a variety of process temperatures. The acid-alkaline-treated surface shows rougher, higher wettability and the presence of oxide of TiO2, as per the averaged results. In a comparison of roughness, wettability, and surface chemistry, no differences are observed between the original and solvent-treated surfaces. The crystalline structure of the surface treated samples reveals alpha and beta phases of Ti6Al4V alloy. However, the alpha 110 peak has only appeared on acid-alkaline substrate. This appearance is probably caused by a change of orientation of the crystallographic plane. Bioactivity results show no differences in Ca-P deposition between the surfaces, leading to CaHPO4, Ca/P~1.0. Some clusters deposit only on the original and solvent-treated surfaces which contain higher Ca-P than the surfaces in the non-cluster region, as observed by SEMEDS. Chemical oxidation treatments are conducted on the original surfaces by the H2O2, 37°C and H2O2, 80°C. Crystalline phases are generally associated with titanium alpha-beta, and a few with anatase and rutile. All the oxidised surfaces are defected by the presence of pores. Ti peaks are seen on the surfaces oxidised by H2O2, 37°C but no longer seen on the surfaces oxidised by H2O2, 80°C, except on the oxidised original surface. TiO2 concentrations are found quantitatively in the Ti 2p and O 1s spectra. A hydroxyl-rich oxides concentration is found at similar levels on all the oxidised surfaces. The oxidised acid-alkaline surface appears to be rougher than the other oxidised surfaces but the effects on the surface hydrophilicity are similar. Bioactivity results show a higher concentration of Ca-P deposits, leading to hydroxyapatite, Ca/P~1.6±0.1. The Ca-P deposition in SBF is increased from 3 to 14 days, as observed by XPS. Thick cluster layers are observed on the oxidised surfaces of the samples incubated for 14 days; these are composed of O, Ca and P; Ca/P~1.5, as observed by SEMEDS. Coating depositions of Ti and TiO2 are performed on the solvent-treated surface. XPS results show no Ti peaks present on the TiO2-deposited surface. The TiO2-deposited surface appears to be rougher and less hydrophilic than other surfaces. No significantly different Ca-P depositions are found on the deposited surfaces as results of CaHPO4 and Ca/P~1.0, which do not exhibit a good bioactive response. The chemically oxidised surfaces show a similarly roughened effect on all the oxidised surfaces. The oxidised Ti- and TiO2-deposited surfaces appear to be more hydrophilic than the oxidised solvent-treated alloys. The chemically oxidised surfaces reveal that Ca-P depositions increase, leading to hydroxyapatite, Ca/P~1.6±0.1 and that there are no differences in the oxidised deposited surfaces of any of the samples incubated from between 3 to 14 days. The Ca-P depositions on the oxidised deposited surfaces are found to have almost half the value of those on the oxidised solventtreated surfaces. The effects of thermal and chemical oxidation on the Ti-deposited samples are investigated. The crystalline structure is transformed from anatase to rutile in an increasing thermal temperature treatment of up to 800°C. At higher magnification, a thin layer with a porous structure is observed on the chemically oxidised surfaces. Shiny oxide layers are seen on the thermally oxidised surfaces. The concentration of atomic oxygen increases as the thermal temperature is increased from 100°C to 800°C, as observed by EDS. The surface chemistry results show that the content of chemically and thermally oxidised surfaces comprises hydroxyl-rich oxides and hydroxyl-poor oxides, respectively. Bioactivity results show that the chemically oxidised surface is able to deposit more Ca-P, leading to the formation of hydroxyapatite, Ca/P~1.7±0.1. However, the thermally oxidised surfaces deposit Ca(H2PO4)2 and, CaCO3 and P2O5 at temperatures of 100°C, 400°C and 800°C, respectively, at Ca/P~0.5. It has been conclusively proved that Ca-P depositions are dependent on the presence of hydroxyl-rich oxides. Apatite nucleation can be formally initiated at the stage of the completion of Ca-P depositions and can actively promote bone-growth after the material has been implanted.
Cumulated Index Medicus
Author: Index Medicus
Author: Publisher:
ISBN:
Category : Medicine
Languages : en
Pages : 2180
Book Description
Vols. for 1963- include as pt. 2 of the Jan. issue: Medical subject headings.
Surface Modification of Titanium for Biomaterial Applications
Author: Kyo-Han KimPublisher:
ISBN: 9781608765393
Category : Coatings
Languages : en
Pages : 0
Book Description
This book starts with concepts of bone, its structure, remodelling, materials for implants and implant testing methods. Calcium phosphate ceramics and need for titanium surface modification are detailed in the initial chapters. Surface modification techniques include plasma spraying, sol-gel, biomimetic, electrochemical, laser, sputtering and ion-implantation methods. Chapters 5 to 19 deal with these modification techniques. Chapters 20-22 deal with less-common methods titanium nitride coating, protein modification, diamond like carbon coating and ultraviolet treatment. Substituting the apatite lattice with other cations like silicon, magnesium, sodium, carbon, etc is provided. The chapters involving these techniques begin with a small introduction about that technique and go on to explain the underlying principles, methodology and properties of the coats. According to the authors, the book gives a complete overview of almost all the surface modification techniques known, as applied to titanium biomaterials.
Bioscience and Bioengineering of Titanium Materials
Author: Yoshiki OshidaPublisher: Elsevier
ISBN: 0080467199
Category : Technology & Engineering
Languages : en
Pages : 447
Book Description
This unique book about bioscience and the bioengineering of titanium materials is based on more than 1,000 published articles. It bridges the gap between the medical/dental fields and the engineering/technology areas, due to the author’s unique experience in both during the last 30 years. The book covers Materials Classifications, Chemical and Electrochemical Reactions, Oxidation, Biological Reactions, Implant-related Biological Reactions, Applications, Fabri-cation Technologies, Surface Modifications, and Future Perspectives. * Provides quick access to the primary literature in this field* Reviews studies of titanium materials in medical and dental applications, as reported in nearly 1,500 articles published over last several years* Draws information from several types of studies and reports* Helps readers answer questions about the most appropriate materials and when to use them
An Investigation of the Bond Strength of Dental Porcelain Fused to Titanium
Author: Jose M. GutierrezAn Investigation of the Bond Strengths of Dental Porcelain Fused to Titanium
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 137
Book Description
In the early part of the 18th century, Fauchard "the father of dentistry", proposed the use of porcelain for making artificial teeth. Since that time, work has never ceased on this fascinating material; and has lead to the highly sophisticated ceramics that are being used today (McLean, 1991). Over the past 25 years, the development of metal ceramic technology has lead to almost universal acceptance of metal-ceramic systems for the fabrication of fixed partial dentures (Campbell, 1989). Biological concerns over existing restorative metal alloys have led researchers to study titanium as an alternate due to its biocompatibility. Titanium is a key metal used by high technology industries, as well as dentistry. Titanium plays a major role in the replacement of the root portion of a tooth; but, also in the replacement of the coronal portion of the tooth (Chance, 1992).
Surface Modification of Titanium by Electrolytic Plasma Processing and In-vitro Studies
Author: Wisanu BoonrawdPublisher:
ISBN:
Category : Biomedical engineering
Languages : en
Pages : 104
Book Description
Electrolytic plasma processing (EPP) can be operated in two modes, namely plasma electrolytic saturation (PES) and plasma electrolytic oxidation (PEO). In this study, the PES was used to create hydrophilic surface profiles on titanium (Ti). The wettability, surface morphology characteristics and chemical composition of the treated samples were studi650ed as a function of PES processing parameters. The PES profiled surfaces comprised of a characteristic "hills and valleys" morphology because of continuous surface melting and freezing cycles. A bimodal surface profile was produced with 2-3 μm height hills and valleys with nano-roughness (≤ 200 nm). The produced profile resulted in a significant contact angle decrease (from 38.7° to 5.4°). Ratios of actual surface area to projection area (r) and fraction of solid surface remaining dry (j) were obtained from profilometry. The surface characteristics and large r values produced by PES were able to induce hemi-wicking. Hence, PES produced superhydrophilic surfaces on Ti. The bioactivity of PES treated Ti was evaluated using cell free and MC3T3 cells in-vitro studies. The treatedi surface significantly increased the bioactivity and formed stoichiometric hydroxyapatite after immersion in a bone cell culture medium for 21 days. Cells' attachment and proliferation studies indicated that PES treated surface significantly enhances the cells' adhesion and growth after 24 and 48 hr compared to the untreated surface. The results show that Ti surface profiling by PES constitutes a promising method to potentially improve bone implant bonding. PEO was used to produce titanium oxide (TiO2) coatings on Ti surface in potassium -phosphate electrolyte. The morphology, wettability, phase, and chemical compositions were studied as a function of processing parameters. The bioactivity of the coating was assessed by the ability to form biomimetic apatite in-vitro using cell culture medium. In-vitro studies using human mesenchymal stem cells were also conducted to evaluate cells' proliferation and viability of the treated Ti. The results revealed that the produced TiO2 coatings comprised pore features with the pore size increasing with applied current density and treatment duration due to high energy discharge channels at higher potential. The PEO treated Ti exhibited superhydrophilic characteristics with a contact angle