Bioceramics zirconia

Hao L, Lawrence J, Chian KS. Osteoblast cell adhesion on a laser modified zirconia based bioceramic. J Mater Sci Mater Med 2005 16 719-26. 

In this chapter, we will attempt to trace briefly the long and sometimes anfractuous history of important bioceramics including coatings. Emphasis will be put on the bioinert ceramics alumina and zirconia, as well as on bioactive, that is osseo-conductive calcium phosphates. 

Afzal, A. (2014) Implantable zirconia bioceramics for bone repair and replacement a chronological review. Mater Express, 4 (1), 1-12. 

Regrettably, no biomaterial is known to date that is both mechanically stable and sufficiently osseoinductive classic bioceramics such as alumina or stabilised zirconia are strong but bioinert, osseoconductive hydroxyapatite is mechanically weak and essentially non-resorbable, whereas the even weaker osseoconductive tricalcium phosphate is resorbable (Figure 3.9). 

Willmann, G. (1993) Zirconia — a medical-grade material Bioceramics, 6, 271—276. 

Kurzweg, H., Heimann, R.B., Troczynski, T., and Wayman, M.L. (1998) Development of plasma-sprayed bioceramic coatings with bond coats based on titania and zirconia. Biomaterials, 19, 1507—1511. 

R. Quan, D, Yang, X. Wu, H. Wang, X. Miao, W. Li, In vitro and in vivo biocompatbility of graded hydroxyapatite-zirconia composite bioceramic, J Mater Sci Mater Med., inpress... 

Nonabsorbable or Relatively Bioinert Bioceramics. 39-2 Relatively Bioinert Ceramics Alumina (AI2O3) Zirconia (Zr02) Carbons... 

Ceramics used in fabricating implants can be classified as nonabsorbable (relatively inert), bioactive or surface reactive (semi-inert) [Hench, 1991,1993] and biodegradable or resorbable (non-inert) [Hentrich et al., 1971 Graves et al., 1972]. Alumina, zirconia, silicone nitrides, and carbons are inert bioceramics. Certain glass ceramics and dense hydroxyapatites are semi-inert (bioreactive) and calcium phosphates and calcium aluminates are resorbable ceramics [Park and Lakes, 1992]. 

Relatively bioinert ceramics maintain their physical and mechanical properties while in the host. They resist corrosion and wear and have aU the properties listed for bioceramics in Table 39.1. Examples of relatively bioinert ceramics are dense and porous aluminum oxides, zirconia ceramics, and single phase calcium aluminates (Table 39.2). Relatively bioinert ceramics are typically used as structural-support... 

Kumar R, Shimizu K., Oka M., Kotoura Y., Nakayama Y., Yamamuro T., Yanagida T., and Makmouchi K. 1989. Biological reaction of zirconia ceramics. In Bioceramics. Proceedings of 1st International Symposium on Ceramics inMedicine. H. Oonishi, H. Aoki, and K. Sawai (Eds.),pp. 341—346, Ishiyaku... 

Bioceramics are used in the human body. The response of these materials varies from nearly inert to bioactive to resorbable. Nearly inert bioceramics include alumina (AI2O3) and zirconia (Zr02). Bioactive ceramics include hydroxyapatite and some special glass and glass-ceramic formulations. Tricalcium phosphate is an example of a resorbable bioceramic it dissolves in the body. Three issues will determine future progress ... 

Table 16.11 Data from Hulbert, S.F. (1993) The use of alumina and zirconia in surgical implants, in An Introduction to Bioceramics, edited by L.L. Hench and J. Wilson, World Scientific, Singapore, p. 30.

FIGURE 13.3 Schematic of micFOStructure in yttrium partially stabilized zirconia (YPSZ) bioceramic undergoing transformation toughening at a crack tip. (From Coles and Stefani, 1995, with permission.)... 

Single oxide ceramics, e.g. aluminium oxide (AI2O3, alumina) and zirconium dioxide (Zr02, zirconia), are bioceramics of an inert nature. An inert ceramic does not form a bonding to bone similar to those bioceramics of bioactive nature. Alumina bioceramics are in the pure aluminium oxide form, whereas zirconia bioceramics are partially stabilized by additional oxides, e.g. yttrium oxide, calcium oxide or magnesium oxide. 

Property ASTM F 603-83 DIN 58 8353 Frialit bioceramic alumina according to ISO/DIS 13356 Prozyr zirconia... 

For orthopedic applications, alumina-zirconia composites have a higher reliability than single-phase ceramics, due to the combined advantages of both the alumina and the zirconia. With the same pre-existing defects, these composites can work at loads two times higher than monolithic alumina without delayed failure and are not susceptible to the hydrothermal instability (low temperature degradation) observed in the case of stabilized—zirconia bioceramics. 

Hydroxyapatite, Caio(P04)6(OH)2, is the main inorganic component found in hard human tissues such as bone and teeth and is the most extensively used bioceramic in bone tissue engineering. The other materials used for this purpose include alumina, zirconia, titania phosphates, and calcium phosphates [such as calcium tetraphosphate (Ca4P209) and tricalcium phosphate Ca3(P04)2] and derivatives [47, 48]. The chemical stmcture of HAp is presented in Fig. 5 [49]. 

Bioceramics Bioceramic materials such as alumina and zirconia exploit exceptional structural stability in a highly corrosive body environment and hence biological inertness, whereas hydroxyapatite and tricaldum phosphate provide functional osseoinductive and osseoconductive properties (Heimann, 2007). 

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 ... 

Bioceramic materials have developed into a very powerful driver of advanced ceramics research and development. For many years bioceramics, both bioinert materials such as alumina, zirconia and, to a limited extent titania (Lindgren et al., 2009), and bioconductive materials such as hydroxyapatite, tricalcium phosphate and calcium phosphate cements, have been used successfully in dinical practice. In addition, applications continue to emerge that use biomaterials for medical devices. An excellent account of the wide range of bioceramics available today has recently been produced by Kokubo (2008), in which issues of the significance of the structure, mechanical properties and biological interaction of biomaterials are discussed, and their clinical applications in joint replacement, bone grafts, tissue engineering, and dentistry are reviewed. The type and consequences of cellular responses to a variety of today s biomaterials have been detailed in recent books (Di Silvio, 2008 Basu et al., 2009 Planell et al., 2009). 

The properties and functions of biomaterials-and in particular of bioceramics - are frequently discussed in the context of hip endoprosthetic implants. Hence, this chapter will focus on the most commonly utilized bioceramic materials such as alumina, stabiHzed zirconia (Y-stabiHzed Tetragonal Zirconia Polycrystal Y-TZP), and calcium phosphates (notably hydroxyapatite), all of which are compo-... 

Mechanical Properties of Advanced Bioceramics Alumina versus Zirconia 1357... 

The future perspectives of bioceramic materials for dental restoration wiU be focused on the development of tougher and esthetically more pleasing glass-ceramics, and also on ceramics such as zirconia with optical properties of color and shine that mimic those of natural teeth and provide a high degree of long-term durability (Holand et al., 2008). The development of nanostructured alumina and... 

Caetano-Zurita, J., Bermudez, O., Lopez-Valero, 1., Stucchi, E.B., Varella, J.A., Planell, J.A., and Martinez, S. (1994) Mechanical behaviour of a hydroxyapatite-zirconia particle composite, in Bioceramics, Proceedings 7th International Symposium on Ceramics in Medicine, Turku (eds O.H. Anderson and A. Yli-Urpo), Butterworth-Heinemann, Oxford, pp. 267-271. 

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