Bioceramic modification

Orthopedic and dental implant materials bioceramics, 145-146 chemical modifications, 147-148 comparing mechanical properties of, and bone, 146 conventional, 127 costs, 126-127 current materials, 145-148 fate of implanted device, 140-141 integration into surrounding tissue, 127 integrin expression on osteoblasts, 144 integrins, 143-144 metals, ceramics, and polymers, 145 next generation, 127,148-159... 

Hydroxyapatite (HAp) and its isomorphous modifications are important and prospective materials in bioceramics. There are some mechanochemical smdies on HAp. In [25] HAp was prepared from calcium hydrated orthophosphates and calcium hydroxide or oxide by mechanical activation of mixtures in planetary mill. The authors... 

State-of-the-art materials for resorbable calcium orthophosphate bioceramics as bone graft substitutes are still TCPs, either as the low temperature modification (0-TCP) or one of the high temperature modifications (a-TCP, a -TCP). The P-TCP is stable below 1125 °C. The a-TCP exists up to 1475 °C, and above this temperature up to the melting point at 1756 °C the a -TCP modification is stable (Figure 4.22). 

The effects of the surface modification of p-CaSi03 on the electrospun poly(butylene sucdnate)/p-CaSi03 composite fibers were investigated (Zhang and Chang 2009). Dodecyl alcohol can be esterified on the surface of p-CaSiOj to modify the bioceramics and prepare the composite fibrous materials with improved properties. Therefore, PBSU/p-CaSiOj composite nanofiber membranes were fabricated by incorporating the surface-modified and surface-unmodified p-CaSiOj into the polymer matrix. 

Spray deposition techifiqnes enable the formation of ceramic or metalhc films onto a snbstrate by spraying the materials in a powder configuration. Among them, plasma-assisted spraying has received special attention in healthcare as it enables the deposition of bioceramics and snrface modification of metallic implants (Nazarpour, 2013). 

The appearance of this type of bioceramics bom of the need to eliminate the interface movement that takes place with the implantation of bioinert ceramics. Consequently, L. L. Hench proposes in 1967 to the U.S.A. Army Medical Research and Development Command, a research based on the modification of the chemical composition of ceramics and glasses so that they have chemical reactivity with the physiological system and form chemical bond between the adjacent tissue and the surface of implant materials. 

MIY 95] MIYAJI F., KIM H.M., KOKUBO T. and NAKAMURA T., Bioactive titanium alloys by chemical surface modification . Proceedings of the 8 International Symposium on Ceramics in Medicine, Bioceramics, vol. 8, p. 323-329,1995. 

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