title: Topological design and additive manufacturing of porous metals for bone scaffolds and orthopaedic implants: A review.
abstract: One of the critical issues in orthopaedic regenerative medicine is the design of bone scaffolds and implants that replicate the biomechanical properties of the host bones. Porous metals have found themselves to be suitable candidates for repairing or replacing the damaged bones since their stiffness and porosity can be adjusted on demands. Another advantage of porous metals lies in their open space for the in-growth of bone tissue, hence accelerating the osseointegration process. The fabrication of porous metals has been extensively explored over decades, however only limited controls over the internal architecture can be achieved by the conventional processes. Recent advances in additive manufacturing have provided unprecedented opportunities for producing complex structures to meet the increasing demands for implants with customized mechanical performance. At the same time, topology optimization techniques have been developed to enable the internal architecture of porous metals to be designed to achieve specified mechanical properties at will. Thus implants designed via the topology optimization approach and produced by additive manufacturing are of great interest. This paper reviews the state-of-the-art of topological design and manufacturing processes of various types of porous metals, in particular for titanium alloys, biodegradable metals and shape memory alloys. This review also identifies the limitations of current techniques and addresses the directions for future investigations.
authors.affiliation: Centre for Innovative Structures and Materials, School of Engineering, RMIT University, GPO Box 2476, Melbourne 3001, Victoria, Australia.
authors.forename: Xiaojian
authors.initials: X
authors.lastname: Wang
authors.affiliation: Centre for Innovative Structures and Materials, School of Engineering, RMIT University, GPO Box 2476, Melbourne 3001, Victoria, Australia.
authors.forename: Shanqing
authors.initials: S
authors.lastname: Xu
authors.affiliation: Centre for Innovative Structures and Materials, School of Engineering, RMIT University, GPO Box 2476, Melbourne 3001, Victoria, Australia.
authors.forename: Shiwei
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Centre for Additive Manufacturing, School of Engineering, RMIT University, GPO Box 2476, Melbourne 3001, Victoria, Australia.
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
authors.affiliation: Centre for Additive Manufacturing, School of Engineering, RMIT University, GPO Box 2476, Melbourne 3001, Victoria, Australia.
authors.forename: Martin
authors.initials: M
authors.lastname: Leary
authors.affiliation: Department of Surgery, University of Melbourne, St. Vincent's Hospital, Melbourne 3001, Victoria, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Choong
authors.affiliation: Centre for Additive Manufacturing, School of Engineering, RMIT University, GPO Box 2476, Melbourne 3001, Victoria, Australia.
authors.forename: M
authors.initials: M
authors.lastname: Qian
authors.affiliation: Centre for Additive Manufacturing, School of Engineering, RMIT University, GPO Box 2476, Melbourne 3001, Victoria, Australia.
authors.forename: Milan
authors.initials: M
authors.lastname: Brandt
authors.affiliation: Centre for Innovative Structures and Materials, School of Engineering, RMIT University, GPO Box 2476, Melbourne 3001, Victoria, Australia; Centre for Additive Manufacturing, School of Engineering, RMIT University, GPO Box 2476, Melbourne 3001, Victoria, Australia. Electronic address: mike.xie@rmit.edu.au.
authors.forename: Yi Min
authors.initials: YM
authors.lastname: Xie
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D008670:Metals / Q000737:chemistry* / Q000494:pharmacology*; D009985:Orthopedics; D016062:Porosity; D019736:Prostheses and Implants; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D008670:Metals
keywords: Additive manufacturing; Biomaterials; Bone scaffold; Orthopaedic implants; Porous metals; Topology optimization