Porous sol-gel Bioglass® from near-equilibrium drying

It has recently been reported that sol-gel derived Bioglass(R) with large pores exhibits a rapid induction of hydroxy-carbonate apatite (HCA) and significant degradability which results in enhanced bone growth[1,2]. In this work, large pore Bioglass(R) has been developed through the sol-gel route with drying under near-equilibrium(liquid/gas) conditions. The water vapor in the near-equilibrium condition creates a pressure inside the pores of the drying gel. This counteracts the capillary pressure responsible for pore deformation which results in a larger pore network. The near-equilibrium drying method to achieve large pores is less expensive, safer and easier for production than supercritical drying without the difficulties in removing residual organics associated with surface modified gels. In addition, crack-free monolithic implants from sol-gel derived Bioglass(R) can also be fabricated by drying under near-equilibrium conditions. This sol-gel derived Bioglass(R) could be an ideal candidate for bone grafting applications.