Application and determination of functional rating scaffoldings in hip prosthesis

Today, depending on the developing additive manufacturing technology, it has become possible to produce personalized, lightweight and highly biocompatible porous implants suitable for the structure of human bones by creating different designs apart from traditional production methods. The fact that the elastic modulus of hip implants is greater than that of bone tissue creates mechanical incompatibility. This causes problems such as loosening, breaking and deformation in implants. In order to minimize the problems in hip joint implants and to increase the adhesion ability of the implant, the manufacturing method was changed and a porous structure was used in the high stressed parts. In this study, hybrid samples with double and triple unit cell models with different pore densities and different unit cell models were produced by 3D printing method, and their mechanical properties were investigated in accordance with the properties of CoCr alloy under axial and radial loads. Porosity ratios, cell model, cell density, shape geometry, printing results of scaffold structures were compared. Chemical cleaning was carried out to minimize dust adhesion and sagging in the inner parts of the scaffolding structures, and the best cleaning results were obtained by using hydrofluoric acid. As a result of the mechanical test, hybrid structures showed different mechanical properties from each other because different porosity ratios and unit cells were used in the scaffold structures. In the double hybrid scaffold models, the maximum stress belongs to the BDWN+TOL model and is measured as 518.20 N, while in the triple hybrid scaffold models, the maximum stress belongs to the OT+BDWN+TOL model and is measured as 475.25 N.