Additive manufacturing technology for porous metal implant applications and triple minimal surface structures: A review

Abstract

Recently, the fabrication methods of orthopedic implants and devices have been greatly developed. Additive manufacturing technology allows the production of complex structures with bio-mimicry features, and has the potential to overcome the limitations of conventional fabrication methods. This review explores open-cellular structural design for porous metal implant applications, in relation to the mechanical properties, biocompatibility, and biodegradability. Several types of additive manufacturing techniques including selective laser sintering, selective laser melting, and electron beam melting, are discussed for different applications. Additive manufacturing through powder bed fusion shows great potential for the fabrication of high-quality porous metal implants. However, the powder bed fusion technique still faces two major challenges: it is high cost and time-consuming. In addition, triply periodic minimal surface (TPMS) structures are also analyzed in this paper, targeting the design of metal implants with an enhanced biomorphic environment.

Impact of Laser Structuring on Medical-Grade Titanium: Surface Characterization and In Vitro Evaluation of Osteoblast Attachment

“…Furthermore, macroscopic porosity can be generated using an Nd:YAG laser in a reduced oxygen atmosphere, as shown in 2010 by Bandyopadhyay et al [16], who performed this technique on the basis of computer-aided design data and titanium alloy powder. At present, this technology is known under the term "additive manufacturing", as summarized in the review by Yuan et al [17]. In general, the impacts of different laser systems have been evaluated for titanium and titanium alloys with the purpose of triggering the adhesion or proliferation of cells on the surface.…”

Current Trends in Improving of Artificial Joints Design and Technologies for Their Arthroplasty

“…The methods of 3D printing of orthopedic products made of polymers by the Fused Deposition Modeling (FDM) method and metals using Direct Metal Laser Sintering (DMLS), developed in recent years, have opened up new possibilities for creating personalized implants (Wong and Scheinemann, 2018;Dall'Ava et al, 2019;Timercan et al, 2019), which, moreover, can be very effective from the point of view of drug delivery to the area of their implantation (Benmassaoud et al, 2019). Despite the fact that additive manufacturing techniques for implants are in the initial stage of development, it can be argued that in the future they will be a powerful means of creating structures with a porous structure, optimal not only in relation to mechanical properties, but also to biocompatibility, bioactivity, and, if necessary and biodegradability (Yuan et al, 2018). Currently, studies of such structures during the replacement of various parts of the body are accumulating, their strengths and weaknesses are being evaluated, and the prospects for their use and improvement from the point of view of orthopedic surgeons are being actively discussed (Han et al, 2019).…”

Functionally graded materials classifications and development trends from industrial point of view

“…Deposition methods represent highly advanced technologies that are used for high accuracy and small products. Liquid-state processes are usually used for large products of relatively lower property control, while solid-state-based FGMS are utilized for highly stressed thermo-mechanical components [37]. The production of FGM by different routes and in different states affects the characteristics of the final product according to the thermal influences, mechanical loading, pressure and inertia forces taking place during manufacturing.…”

“…Complex shapes are possible Low cost for prototyping From art to part directly (min. tooling) High accuracy High repeatability Secondary finishing operation is required Mainly produce discrete structure Very high specific energy consumption Huge equipment costs in case of metal products Lower productivity rates [37,[103][104][105] Plasma spray forming Simultaneous melting of metallic and highly refractory phases, blending the two in ratios that can be present by control of the feeding rates of the powders of the two materials…”