Biocomposite of Hydroxyapatite/Gelatin/PVA for Bone Graft Application

A porous block composite of Hydroxyapatite/Gelatin/Polyvynil Alcohol has been successfuly fabricated as a bonegraft. The porous block of composite was examined to investigate its compressive strength, micro structure and callus formation. Materials for the composite were hydroxyapatite synthesized from calcite (coHA), commercial hydroxyapatite (HA-200), gelatin (G) and polyvynil alcohol (PVA). The porous block composite was prepared from a solution, by mixing the loading material and distilled water with ratio of 5, 15 and 250% w/v. The loading material was made by blending of HA (coHA or HA-200), G and PVA with weight composition ratio of 1/1/0.15. To develop a porous block, the solution of composite was casted in a mold and freezed overnight prior to freeze-drying for 6 hours at 0.02 Bar and -50°C. Tests were performed on compression strength, microstructure, pore size and in vivo. The in vivo test was carried out by observing a callus growth within cancellous bone of white rat for 14 and 21 days. The results showed that the graft composed by coHA and HA-200 had average pore size of <;10 μm up to 300 μm with compressive strength of 3 to 5 MPa. These strengths were in the range of trabecular bone strength. From the in vivo test, composite of [HA200/G/PVA] showed better callus growth compared to [CoHA/G/PVA] and the control.