Material Challenges and Opportunities in 3D Printing for Hip Implant Applications

Abstract

There is a current need for tissue and organ repairs, replacement, and regeneration for patients who suffer from diseased or damaged tissues or organs. This situation is continuously on the rise and the supply of this form of therapy does not meet the patients demand mostly due to lack of donors and biocompatibility issues which causes immune system rejection of the implants. To succeed through these limitations, researchers are currently investigating the use of scaffolds as another approach for implants. The conventional scaffold fabrication technique is limited due to the precision of pore design. The 3D printing technology on the other side can produce an extracellular matrix with a higher degree of complexity and matching details such as pore size and geometry suitably based on certain factors including tissue engineering, hip biomechanism, material suitability, ethical standards, future, and challenges. This paper in particular focuses on materials challenges and opportunities addressing various issues at various levels to the materials-process-property relationship. It is comprehensive as it starts with hip biomechanism in gait and stress distribution to give the reader a clear perspective of the magnitude of challenges for hip implants and details to consider when designing the materials. This is followed by 3D printing for orthopaedic applications and 3D hip tissue regeneration. The hip replacement materials including polymers, composites, and metals are explored and correlated to conventional hip replacement materials. The work is concluded with some concluding remarks on opportunities, challenges, and future trends. The goal is to have scaffolds that have the capability of having a biomimicking design similar to the extracellular matrix with the advantage being the provision of structural supports for cell attachment, growth, and differentiation with the main goal of producing an operational organ or tissue. The knowledge derived from this review offers huge potential for providing a pathway for sustainable healing.