Bone tissue engineering is the field of intense research for developing new 3D scaffolds with hierarchical and highly interconnected porous structure. which should match the properties of the tissue that is to be replaced. These materials need to be biocompatible, ideally osteoinductive, osteoconductive and mechanically well-matched. In the present study, we report the development and characterization of novel hybrid macroporous scaffolds of poly(vinyl) alcohol (PVA)/bioactive glass (BaG) through the sol-gel route. The organic-inorganic hybrids with three concentrations of PVA (80, 70 and 60 wt%) and bioactive glass (58SiO(2)-33CaO-9P(2)O(5)) were synthesized by foaming a mixture of polymer solution and bioactive glass via sol-gel precursor solution. PVA with two degree of hydrolysis, 98.5% (high degree) and 80% (low degree) was also investigated, in order to evaluate the influence of residual acetate group present in polymer chain on the final structure and properties of 3D porous nanocomposites produced (PVA/BaG). Bioartificial polymeric hybrids were also investigated in this work by blending PVA with chitosan (chi) and then reacting with bioactive glass reagents using sol-gel processing route (PVA/Chi/BaG). The microstructure, morphology and crystallinity of the hybrid porous scaffolds were characterized through synchrotron small-angle X-ray scattering (SAXS), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analysis. In addition, mechanical properties of hybrids were evaluated by uni-axial compression tests. Biocompatibility, cytotoxicity and cell viability assays were also performed by the MTT method with VERO cell culture. The results have given strong evidence that both hybrid systems of PVA/bioactive glass and PVA/chitosan/bioactive glass were successfully produced and extensively characterized with hierarchical macroporous 3D structure. FTIR spectroscopy associated with XRD and SAXS has proven to be important technique for investigating the formation of PVA/BaG and PVA/Chi/BaG hybrids as organic-inorganic network at micro-nanostructure order. Finally, the developed hybrids have presented suitable mechanical, morphological and cell viability properties for potential biological applications. (C) 2007 Elsevier B.V. All rights reserved.