Setting Behavior and Drug Release from Brushite Bone Cement prepared with Granulated Hydroxyapatite and β-Tricalcium Phosphate

Abstract

Calcium phosphate bone cement was prepared to contain antibiotics for release after setting using granulated β-tricalcium phosphate (β-TCP) and hydroxyapatite (HA). Gentamicin sulfate (GS) solution was infiltrated within the interconnected pores of the granule to avoid affecting the setting reaction and for protection of GS during the setting. Consequently, the setting time and the temperature increase were not affected, regardless of the loading of GS. The release of the GS from the cement was estimated by measuring the concentration at regular intervals from the cement dipped solution. The β-TCP granule loaded with GS exhibited the saturation of accumulative concentration at 16 h. In contrast, the HA granule with GS exhibited steady increase in accumulative concentration of over 10 μg/ml at 144 h. Thus, the granulated cement could release the GS greater than the minimum inhibitory concentration of staphylococcus during the prescription peroid of the oral antibiotics. Key words: Bone cement, Granule, Gentamicin, Hydroxyapatite, β-TCP