2005 Volume 19 Pages 106-111
Hydroxyapatite ceramics has been paid attention as bone filler, and bone graft substitutes, due to its biocompatibility and osteo-conduction. Recent studies have found a new surface functionalisation method for creating favorable local conditions that lead to nucleation and growth of calcium phosphate over substrates. Phosphorylation is a surface functionalization method for that purpose. Authors have conducted calcium phosphate coating over chitosan films that were produced by a process based on phosphorylation, Ca(OH)2 treatment and SBF immersion. The obtained samples were commercial chitin, phosphorylated chitin, Ca(OH)2 treated phosphorylated chitin and Ca(OH)2 treated phosphorylated chitin after immersion in SBF solution. These materials were implanted at cranial bone of rats, and the biocompatibility was estimated. 4 weeks after implantation, fibrous tissues were observed between bone and commercial chitin or phosphorylated chitin material. Little fibrous tissue, although was found in the interface between bone and Ca(OH)2 treated phosphorylated chitin after immersion in SBF solution. The Ca(OH)2 treatment and SBF immersion facilitates the formation of a calcium phosphate over the phosphorylated samples in vivo as well as in vitro.
