To Improve Total Knee Prostheses Performance Using Three-Phase Ceramic-Based Functionally Graded Biomaterials

Abstract

One of the common issues that occur after total knee replacement surgery is the aseptic loosening. The problem usually occurs after about 15 years from the surgery. The destructive effects of residual particles due to wear, the stress shielding effect, and micro-movements are the causative factors for this type of loosening. In this research, using the advantages of functionally graded biomaterials (FGBM), it is tried to design a prosthetic system that can reduce the above-mentioned effects. For this purpose, the materials used in the most important part of the prosthesis system, i.e., the femoral part are redesigned so that the bioactivity between the prosthesis and bone, and the stress applied to the adjacent tissues increase simultaneously. In addition, to reduce the effect of wear at contact areas, wear-resistant biocompatible ceramics such as alumina and zirconia are used. The value of stress at the bone-prosthesis interface and adjacent tissues is the most important parameters. Two types of three-phase ceramic-based FGBMs are recommended. The prosthesis with three-phase hydroxyapatite-titanium-zirconia has increased the average stress in the bone tissues around high-risk areas up to 71.8% with respect to a commonly used Cr-Co prosthesis. The result for the prosthesis with three-phase hydroxyapatite-titanium-alumina is up to 65%, respectively. At bone-prosthesis interfaces, an increase of 92% in the stress for both zirconia-based and alumina-based is seen. Briefly, the recommended FGBMs can improve the bone-prosthesis performance in all desired indices.

A numerical investigation for the development of functionally graded Ti/HA tibial implant for total ankle replacement: Influence of material gradation law and volume fraction index

“…This is a better approach than dividing the tibial implant into different layers/ slices and then assigning different properties to each layer as done by the earlier researchers. [28][29][30]34 In the layered approach, the material variation is not gradual between the interfaces of the subsequent layers. Additionally, in this approach, the number of elements can be increased to achieve a more continuous and uniform FGM distribution.…”

“…27 FGMs have already been successfully used in total hip replacement (THR) 26,[28][29][30][31] and total knee replacement (TKR). [32][33][34][35] Enab et al 26 proposed FGM hip implants of different titanium alloys layered with HA and reported an increase in bone von Mises stress with FGMs. Moussa and Yadav 28 performed a study on FGM stem for the femoral component of THR, and showed lesser stress shielding with FGM implants compared with Ti alloy implants.…”

“…Therefore, the preclinical biomechanical analysis can be done using finite element (FE) analysis similar to the earlier published work. 26,[28][29][30][31][32][33][34][35] Thereafter, stress shielding and implant-bone micromotion can be studied, which are the important parameters for evaluating the performance of TAR. 37,38 The objectives of this study are (1) to design the tibial implant for TAR with FGM using three-dimensional (3D)FE models of intact and implanted tibiae and (2) to investigate the influence of material gradation law and volume fraction index on stress shielding and implant-bone micromotion.…”

A Review on Functionally Graded Materials and Their Applications in the Field of Prosthetics

“…They concluded that the gradation direction considerably affects the bone adaptation procedure. The results showed that using a radial FGM with low-stiffness material in the outer layer and less metal composition significantly improves the bone remodelling behaviour., Ayatollahi et al, [55] improve the performance of the bone prosthesis system and prevent the aseptic loosening in a total knee replacement surgery using two types of ceramic based functionally graded biomaterials, alumina based and zirconia based FG biomaterials. Both the alumina based and zirconia based FG biomaterials showed significantly better performance compared to commonly used Cr.Co prosthesis.…”

The status and challenges of replicating the mechanical properties of connective tissues using additive manufacturing

“…Many different studies have created FGBMs by varying the size of the lattice unit cell throughout the material to alter the stiffness of the scaffold in different locations (Mahbod and Asgari, 2019;Torres et al, 2016;Zhang et al, 2019). Ayatollahi et al (2019) have proposed a 3-phase ceramic based FGBM, which uses HA, alumina or zircona, and titanium all within the same component to provide different material properties in different locations on a knee implant. The use of FGBMs is also being investigated to develop artificial blood vessels.…”