Nicky Bertollo, Masaaki Matsubara, Tsuyoshi Shinoda, Dong Chen, Mukesh Kumar, William R. Walsh
Porous scaffold dowels of Ti6Al4V were prepared and implanted into cancellous and cortical bone sites in adult sheep. Cancellous implants were examined under gap, line-to-line, and press-fit conditions, whereas line-to-line implantation was used in cortical sites. Cortical shear strength increased significantly with time and reached 26.1 ± 8.6 MPa at 12 weeks, accompanied by a concomitant increase in bone integration and remodeling. In cancellous sites, bone integration was well established at 4 and 12 weeks under conditions of press-fit and line-to-line match between implant and surgical defect. New bone growth was also found in the gap conditions, although to a lesser extent. These findings suggest that the porous Ti6Al4V could prove an effective scaffold material for uncemented fixation in cortical and cancellous sites.