Extra low interstitial titanium based fully porous morphological bone scaffolds manufactured using selective laser melting

J Mech Behav Biomed Mater. 2019 Jul:95:1-12. doi: 10.1016/j.jmbbm.2019.03.025. Epub 2019 Mar 28.

Abstract

Lattice structure based morphologically matched scaffolds is rapidly growing facilitated by developments in Additive Manufacturing. These porous structures are particularly promising due to their potential in reducing stress shielding and maladapted stress concentration. Accordingly, this study presents Extra Low Interstitial (ELI) Titanium alloy based morphological scaffolds featuring three different porous architecture. All scaffolds were additively manufactured using Selective Laser Melting from Ti6Al4V ELI with porosities of 73.85, 60.53 and 55.26% with the global geometry dictated through X-Ray Computed Tomography. The elastic and plastic performance of both the scaffold prototypes and the bone section being replaced were evaluated through uniaxial compression testing. Comparing the data, the suitability of the Maxwell criterion in evaluating the stiffness behaviour of fully porous morphological scaffolds are carried out. The outcomes show that the best performing scaffolds presented in this study have high strength (169 MPa) and low stiffness (5.09 GPa) suitable to minimise stress shielding. The matching morphology in addition to high porosity allow adequate space for flow circulation and has the potential to reduce maladapted stress concentration. Finally, the Electron Diffraction X-ray analysis revealed a small difference in the composition of aluminium between the particle and the bonding material at the scaffold surface.

Keywords: Additive manufacturing; Extra low interstitial; Mechanical performance; Morphological scaffold; Selective laser melting; Stress shielding.

MeSH terms

  • Alloys
  • Compressive Strength
  • Lasers*
  • Materials Testing
  • Phase Transition*
  • Porosity
  • Tibia / cytology*
  • Tibia / diagnostic imaging
  • Tibia / drug effects
  • Tissue Scaffolds / chemistry*
  • Titanium / chemistry*
  • Titanium / pharmacology
  • X-Ray Microtomography

Substances

  • Alloys
  • titanium alloy (TiAl6V4)
  • Titanium