Enhancement of the porous titanium with entangled wire structure for load-bearing biomedical applications

• The porous titanium with entangled wire structure was enhanced by PMMA.
• Its tensile elastic modulus reached about 1 GPa at porosity of 53.4%.
• Its preferred pore size and the good connectivity were still maintained.
• PMMA enhancement was more effective than the sintering.
• It reveals superiorities in stiffness and cost.

The porous Ti with entangled wire structure has been developed for the biomedical application. But its stiffness is lower than that of the conventional porous Ti due to the structural flexibility. In order to enhance the stiffness, the free cross wire nodes in the entangled structure must be fixed. In this study, a medical polymer – polymethylmethacrylate (PMMA) was selected as the bonding agent to fix the cross wire nodes. The method to enhance the porous Ti by the PMMA was described in detail. The tensile mechanical properties of the PMMA-enhanced porous Ti were investigated. The result indicated that this method was more effective than the sintering, and achieved about 1 GPa tensile elastic modulus, while the porosity only decreased from 55% to 53.4%. Although some PMMA was coated on the Ti wire surface, the preferred average pore size and the good connectivity were still maintained in the PMMA-enhanced porous Ti materials. This is very beneficial to the bone grafting application.