Bioceramics 21: Selected papers from 21st international symposium on ceramics in medicine the annual meeting of the internatiional society for ceramics in medicine )ISCM(; Buzios, Brazil, 21-24 October 2008proceedings of the 16th International Symposium on Ceramics in Medicine, the annual meeting of the International Society for Ceramics in Medicine : bioceramics -- 16, Centro de Congressos da Alfعndega do Porto, Porto, Portugal, 6-9 November, 2003