Porous hydroxyapatite, a bioceramic with high biological affinity and similar composition to the bone mineral, has attracted a lot of interest. To produce a biomaterials with compositions close to bone mineral different ions have been substituted in hydroxyapatite structure, Fluor and magnesium substitution in hydroxyapatite structure have been investigated to improve its biological and physical properties. It is expected that addition of diopside, a glass-ceamic with high mechanical strentgh and bioactivity, to magnesium-fluorapatite lead to higher mechanical and biological properties. In this study, magnesium-fluorapatite foams with 10, 20 and 30 weight percent diopside were fabricated via gelcasting method. The porosity and mechanical properties of the foams were measured by Archimedes method and compressive tests respectivly. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM) were used to evaluate and characterize phase structure and composition, crystallite size and pore size and morphology. To evaluate the bioactivity and bioresorbability of the foams, soaking test in Ringer’s solution was performed. SEM and Fourier Transform Infrared Spectroscopy (FTIR) were used for verification and charactrization of apatite formation. Ion release was determined by inductive coupled plasma optical emission spectroscopy (ICP- OES). Results showed that, nanostructured magnesium-fluorapatite/diopside foams with 50-70% porosity were fabricated perfectly. Apatite layer formation was confirmed on all foams. magnesium- fluorapatite foam with 10 wt% diopside exhibited maximum strength (6 MPa) and magnesium-fluorapatite foam with 30 wt% diopside showed maximum bioactivity. In conclusion, magnesium-fluorapatite/diopside foams exhibiteed bioactive behavior with acceptable mechanical properties and could be good candidates for bone tissue engineering applications. Keywords : magnesium-fluorapatite, Gelcasting, diopside, nanocomposite foam, sol-gel, magnesium-fluorapatite/diopside nanocomposite.
