A chitosan composite material for bone replacement

A mineral-filled chitosan composite was characterized and evaluated for suitability as a bone graft substitute. Chitosan was selected as a matrix material due to its biodegradability and inherent wound healing properties. The mineral component of bone, hydroxyapatite, was chosen as a filler. Compositions were varied by changing the amount of polymer contained in the matrix as well as the percentage of filler contained in the composite. The evaluation of mechanical properties included three-point bend, double shear, and tensile testing. Samples were tested first in a dry condition, as well as after immersion in Ringer's solution. Scanning electron microscopy was performed on all the dry samples. It was observed that the mechanical properties of the composites in the dry condition improved as percentage of polymer in the matrix increased and as filler content decreased. Upon exposure to a physiological fluid the mechanical properties of the wet composites improved as filler content increased.