One Monitoring and evaluation of the mechanical performance of biomaterials in vivo

Nanostructured ceramics

L. Hermansson

Doxa AB and Applied Research Sweden AB, Uppsala, Sweden

I ntroduction

Ceramics are defined as inorganic nonmetallic materials and are often classified according to Table 1.1. Biomaterials based on ceramics are found within all the classical ceramic families: traditional ceramics, special ceramics, glasses, glass ceramics, coatings, and chemically bonded ceramics (CBC) [1,2]. Examples of bioceramics are given in Table 1.1.

This chapter deals specifically with bioceramics with nanostructures. The nanosize is defined as less than 100 nm. Nanostructured ceramics are found most frequently among the CBC [1] shown in Table 1.2.

The nanostructured chemically bonded ceramics have structures with the same general structure as hard tissue, i.e., small crystals, all surrounded by a softer interlayer, in the case of hard-tissue collagen layers, and in the case of the chemically bonded silicate, aluminate, and phosphate ceramics, nanothin water layers. The structures of all the apatite-based body ceramics (enamel, dentine, and hard tissue) include individual plates just above the nanosized level, approximately 0.2 gm, but composed of nanocrystals of approximately 20 nm in diameter [1,3].

Nanostructured bioceramics are also, to some extent, found within the special ceramics field based on zirconia, titania, silica, or other oxides produced by low-temperature sintering using laser techniques, hot pressing, or hot isostatic pressing [4,31].

This chapter will treat nanostructured ceramics with emphasis on nanostructured materials, not nanostructured particles, needles, wires et cetera.

 
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