Osseointegration assessment of multi-material Ti6Al4V-βTCP implants: an experimental study in rats

Abstract

In the present study, mono- and multi-material laser textured Ti6Al4V implants are manufactured and characterized in vivo to explore their applicability in orthopedic implants. Laser surface texturing is used for manufacturing grooved Ti6Al4V implants while a pressure-assisted sintering technique is employed to impregnate beta-tricalcium phosphate into grooves for an improved bioactivity. After implantation into Sprague Dawley rat's femur for 4 and 12 weeks, bone-implant fixation and osseointegration are assessed, by performing push-out tests and histological characterization. Histological characterization showed bone formation around all implants, characterized by immature bone at 4 weeks of implantation and a more mature bone after 12 weeks. The maximum push-out forces are higher for the textured and multi-material solution, when compared to non-textured implants right after 4 weeks of implantation (p < 0.05). After 12 weeks, multi-material implant displayed higher fracture energy when compared to non-textured implants (p < 0.05). Results revealed that laser surface texturing and bioactive multi-material solutions are highly effective to promote bone regeneration and enhance bone-implant fixation for further application in orthopedic implants.