Biocompatibility of anionic collagen matrix as scaffold for bone healing

The basic approach to the treatment of bone defects involves the use of sca ffolds to favor tissue growth. Although several bioscaffolds have been prop osed for this purpose, the search for new and enhanced materials continues in an attempt to address the drawbacks of the present ones. Modifying curre nt materials can be a fast and cheap way to develop new ones. Among them, t ype I collagen allows its structure to be modified using relatively simple techniques. By means of an alkaline treatment, anionic collagen with enhanc ed piezoelectric properties can be obtained through hydrolysis of carboxyam ides groups of asparagine and glutamine residues from collagen in carboxyli c. The process applied to a raw source of collagen, bovine pericardium, pro vided a sponge-like structure, with heterogeneous pore size, and, moreover, the complete removal of interstitial cells. For the evaluation of the bioc ompatibility of such matrices, they were implanted in surgically created bo ne defects in rat tibias. Empty defects served as controls. This experiment al model allowed a preliminary evaluation of the osteoconductiveness of the matrices. The histological results presented a low inflammatory response a nd bone formation within a short period of Lime, similar to that of control s. The low cost of production associated to the biocompatibility and osteoc onductivity performance make the anionic collagen matrices promising altern atives for bone defects treatment. (C) 2001 Elsevier Science Ltd. All right s reserved.