Development of injectable chitosan/biphasic calcium phosphate bone cement and In Vitro and In Vivo evaluation.

Injectable Biphasic calcium phosphate bone cements (BCPCs) composed of beta-tricalcium phosphate (beta-TCP) and hydroxyapatite (HA) have been intensively investigated because their high biodegradation rate, bioactivity and osteoconductivity which can be adjusted by changing the ratio between beta-TCP and HA phases after setting. The aim of this study was to evaluate the performance of 1 wt% chitosan fiber additive with biphasic calcium phosphate for injectable bone cement both in vitro and in vivo. The in vitro testing of compressive strength, degradation rate, morphology, cell and alkaline phosphatase (ALP) activities were evaluated by comparing with the bone cement without beta-TCP. The in vivo testing of micro CT-scanning and histological examinations between three groups of Control, BCPC and commercial biphasic calcium phosphate granule were characterized and compared. After adding beta-TCP of 20 wt%, the initial and final setting times of the sample were 3.92 min and 11.46 min, respectively, which were not significantly changed as compared with the sample without beta-TCP. The degradation time of the BCPC material will be increased more than CPC alone. The healing process was significantly faster in BCPC than those in control and commercial product. Therefore, this is the first evident that BCPC are attractive for bone surgery due to its faster healing stimulation with faster degradation rate.