Bioceramics biocompatibility

Black, J. and G. W. Hastings. 1998. Handbook of Biomaterial Properties. London/New York Chapman and Hall. This is a compilation of data on natural tissues and fluids and how various implantable materials interact with than. The materials covered range from stainless steels, CoCr-based alloys, titanium, and titanium alloys, to thermoplastic polymers and oxide bioceramics. Biocompatibility is discussed with each material and in a chapter on general concepts of biocompatibUity. Available online on Knovel. 

A third class of bioceramics are based on Zr02, stabilized by Y2O3 or Ce02. These materials are close to aluminum oxide materials in terms of biocompatibility but exhibit a higher bend strength and crack resistance, though with lower compressive strength. Zirconium dioxide ceramics can be used for many of... 

Aluminate compositions include calcium aluminate cements, which have high chemical resistance, especially to sulfate, and is also used in refractory applications where ordinary Portland cements would be unsuitable. These same cements are used in bioceramic applications. The bioceramic applications reflect both the high mechanical strength of the calcium aluminate cements and also the biocompatibility of Ca-bearing phases, which bond well with, for example, bone. 

As to the biomaterial for human tissue replacement, it is necessary to demonstrate if the material has any effect on the biological properties of the tissue. Bioceramics exhibit some possible toxic reactions due to metal ions leaching from the ceramics, resulting in the tissue dying or heavy reactions. In this experiment, cytotoxicity test, hemolysis test as well as skin irritation were conducted to value the biocompatibility of the porous AI2O3 ceramics. 

Bioceramics Bioinert ceramics Bioinert (is not rejected), biocompatible Replacement/repair of teeth, coatings, root pins, crowns... 

The main advantage of ceramics over other implant materials is their biocompatibility some are inert in the physiological environment while others have a controlled reaction in the body. The main disadvantages of most bioceramics are... 

Carbon is an important bioceramic. It combines outstanding biocompatibility and chemical inertness. Carbon exists in many forms, some of which have been discussed in earlier chapters. The most important form of carbon... 

FTIR spectroscopy has proven to be particularly useful in gaining an understanding of the biocompatibility phenomenon. It is believed [746, 841, 856, 857] that protein adsorption is the initial step in the interaction of blood with implanted biomaterials, followed by adhesion of cells and subsequent tissue attachment. This implies that the substrate surface characteristics influence the process, which was confirmed by ATR studies of albumin adsorption on calcium phosphate bioceramics and titanium [763] and segmented polyurethane [764], albumin and fibrinogen on acetylated and unmodified cellulose [765, 766], poly(acrylic acid)-mucin bioadhesion [767], polyurethane-blood contact surfaces [768], and other proteins on poly(ester)urethane [769], polystyrene [767, 771] and poly(octadecyl methacrylate) [771] and by IRRAS study of adsorption of proteins on Cu [858]. Another branch of IR spectroscopic studies of protein adsorption relates to microbial adhesion (Section 7.8.3). 

The idea of using polymers as binders for particulate bioceramics to prepare biocomposites with improved processing and retention characteristics and to overcome the problem of poor mechanical properties was reported. Poly(rac-lactide) (PDLLA) is a thermoplastic biodegradable, resorbable, and biocompatible aliphatic polyester, which in recent years received significant attention in the biomedical research field. It was also generally viewed as a polymer of the future because... 

One field of application with a large potential is that of bioceramic coatings based on hydroxyapatite and second-generation bioceramics. Such biocompatible coatings for bone implants have promising apphcations to solve some of the health problems of an aging population (Hench, 1991 Heimann, 2007 Heimann 2008 see also Chapter 10). 

Bioceramic Applications The performance requirements of yttria-stabilized tetragonal zirconia polycrystal (TZP) to form biocompatible, strong components for use as hip, knee, and dental prostheses, and which demonstrate long-term resistance against aggressive body fluids and mechanical wear and tear, during a predicted lifetime of 15-20 years in the human body, include ... 

Phase and chemical composition of bioactive materials is selected so as to ensure that implant surface adjacent to tissue or body fluids constitutes an intermediate layer which connects an implant with bone tissue. A variety of materials which fulfil such criteria have been developed in recent years. The most frequently used bioceramics, due to their high mechanical, corrosion and wear resistance as well as their non-toxicity and biocompatibility, include oxides AI2O3 (whose use for medicine is dated back to the thirties of the past century), Zr02 and calcium phosphates (Tab. 1, 2). 

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