Functional bioceramics

There have been several studies to evaluate the potential of calcium alumi-nates as functional bioceramics (Hulbert, Morrison and Klawitter, 1972). The advantages of this material include its compositional variability the different phases of which provide different rates of hydrolysis so that the overall resorption rate can be controlled. The release of Al ions in large concentrations into the... 

Komath, M., and Varma, H. (2012) Preparation and analysis of chemically gradient functional bioceramic coating formed by pulsed laser deposition. /. Mater. Sci. Mater. Med., 23 (2), 339-348. 

M.M. Pereira, J.R. Jones, L.L. Bench, Bioactive Glass and Hybrid Scaffolds Prepared by Sol-Gel Method for Bone Tissue Engineering, Advances in Applied Ceramics Structural, Functional Bioceramics, 104(1), 35-42 (2005). 

Tamura, K. et al. (2004) Effects of micro/ nano particle size on cell function and morphology, Bioceramics 26 (eds Barbosa, M.A., et al.), Trans Tech Publications, Uetikon-Zurich, pp. 919-922. 

Deposition, Structure, Properties and Biological Function of Plasma-Sprayed Bioceramic Coatings... 

Osteopontin (formerly known as bone sialoprotein I) binds tightly to hydroxyapatite in bone and thus forms an integral part of the mineralised matrix. It has been postulated to be a ligand for the vitronectin receptor, and this suggests a possible role of osteopontin in osteoclast attachment and function (Merry et al., 1993). Hence, it functions as a potent marker of ossification and consequently its expression serves to quantify the degree of mineralisation of bone tissue in contact with bioceramic materials including coatings. 

Bioceramic coatings are often used on metallic substrates in which the fracture toughness of the metal is combined with the ability of the coating to present a bioactive surface to the surrounding tissue. The use of a bioceramic coating on a metal implant can lead to earlier stabilization of the implant in the surrounding bone and extend the functional life of the prosthesis. Under the proper conditions a cementless prosthesis should remain functional longer than a cemented device in which stability is threatened by fracture of the bone cement. 

Calcium-idiosphate-based bioceramics have also been used as coatings on dense implants and porous surface layers to accelerate and enhance fixation of a substrate biomaterial to tissue (Kohn and Ducheyne, 1992 Cook et al 1992 Ducheyne et al., 1980 Oonishi et al., 1994). Results of these smdies vary with respect to bond strength, solubility, and overall in vivo function, suggesting a window of material variability in parallel with a window of biologic variability (Kohn and Ducheyne, 1992). 

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