الفهرس 
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Abstract
Porous biomaterials fabricated by additive manufacturing (AM) technologies provide opportunity for orthopedic applications. This research has investigated the influence of using three different porous Titanium alloy (Ti6Al4V) structures; face centered cubic with vertical struts, reentrant and rhombic-dodecahedron for artificial tibia implant of total knee replacement (TKR) using a finite element method (FEM). The porous tibia joint implants were modeled using CATIA software. Then, three- dimensional finite element analysis (FEA), using ANSYS software, was conducted. The stress distributions of porous tibia-knee implants were compared to solid-stem implant under physiological human weight during stance phase through normal walking. The differences of scaffold design structures, unit cell and porosity with the same pore size for tibia-knee implantation demonstrated different performance on stress distributions. A comparison between maximum von-Mises stresses on the bone surface under the tibia-tray of porous tibia-knee implants and solid-stem implant indicated that higher stresses are generated in porous tibia-knee implants. Additionally, lower stresses are generated in porous-stem tibia implants on both bone/stem interface and stem-end region compared to solid-stem implant. Lower stress shielding and bone loss are predicted in case of using porous implanted tibia-knee joint. Also the risk of both micro-motion of implant/bone interface and stem-pain are predicted to decrease. Controlling the structure design and features; unit cell and porosity of cellular Ti6Al4V optimize the mechanical properties. Consequently, the effects of stress shielding and stresses in both bone/stem interface and stem-end region are predicted to reduce. The reduction of bone loss rate will reduce the risk of implant failure and the need for revision surgery. Proof of concepts, face centered cubic with vertical struts, reentrant and rhombic- dodecahedron lattice implants were fabricated as prototypes for the proposed designs. Acrylonitrile-Butadiene-Styrene (ABS-like resin) was used to prototype the proposed models using Phrozen Shuffle XL Printing Machine. The average pore sizes of the cellular implants were measured via Scanning Electron Microscope (SEM) to demonstrate the ability to be manufactured.