Effect of Porosity on the Static and Impact Response of Titanium in Implants used insideFemur Bone

The high difference between mechanical properties oftitanium implants and bone creates stress shielding effectat the bone/implant interface which decreases thedurability of the implant. Low stiffness of porous titaniumbiomaterials decrease the mechanical properties mismatchbetween implant and bone tissue. In this research, effectof porosity of the inserted implant on the mechanicalbehavior of cortical bone of a simplified femur bonestructure is studied. After inserting the implant, theimposed stress on the cortical bone should not be muchhigher or lower than that in a natural femur bone. In thisstudy the stress distribution on the cortical bone wasinvestigated for different cores (cancellous bone, titanium,titanium with porosities of ۴۲, ۵۲ and ۷۲ %) under staticand impact loadings. For the static loading, standingposition of a ۷۵ kg person, and for the impact loading,landing of the same person in a gymnastics competitionwas considered. Comparison the results of cores withdifferent porosities showed that in a static loading, the lowporosity (۴۲%) titanium and for the impact loading, thehigh porosity (۷۲%) titanium can better follow thebehavior of cancellous bone.

کلیدواژه ها:

Impact ، Implant ، Titanium foam ، FiniteElement ، Femur