To fulfill the properties of barrier membranes useful for guided bone tissue regeneration in the treatment of periodontitis, in this study a simple process combining lyophilization with preheating treatment to produce asymmetric barrier membranes from biodegradable chitosan (CS) and functional β-tricalcium phosphate (TCP) was proposed. By preheating TCP/CS (3:10, w/w) in an acetic acid solution at 40°C, a skin layer that could greatly increase the mechanical properties of the membrane was formed. The asymmetric membrane with a skin layer had a modulus value almost 4-times that of the symmetric porous membrane produced only by lyophilization. This is beneficial for maintaining a secluded space for the bone regeneration, as well as to prevent the invasion of other tissues. The subsequent lyophilization at -20°C then gave the rest of material an interconnected pore structure with high porosity (83.9-90.6%) and suitable pore size (50-150 μm) which could promote the permeability and adhesiveness to bone cells, as demonstrated by the in vitro cell-culture of hFOB1.19 osteoblasts. Furthermore, the TCP particles added to CS could further increase the rigidity and the cell attachment and proliferation of hFOB1.19. The TCP/CS asymmetric composite membrane thus has the potential to be used as the barrier membrane for guided bone regeneration.
Journal of Biomaterials Science: Polymer Edition 23(9), pp.1153-1170