Mechanical properties and in vitro behavior of additively manufactured and functionally graded Ti6Al4V porous scaffolds

Ezgi Onal, Jessica E. Frith, Marten Jurg, Xinhua Wu, Andrey Molotnikov

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Functionally graded lattice structures produced by additive manufacturing are promising for bone tissue engineering. Spatial variations in their porosity are reported to vary the stiffness and make it comparable to cortical or trabecular bone. However, the interplay between the mechanical properties and biological response of functionally graded lattices is less clear. Here we show that by designing continuous gradient structures and studying their mechanical and biological properties simultaneously, orthopedic implant design can be improved and guidelines can be established. Our continuous gradient structures were generated by gradually changing the strut diameter of a body centered cubic (BCC) unit cell. This approach enables a smooth transition between unit cell layers and minimizes the effect of stress discontinuity within the scaffold. Scaffolds were fabricated using selective laser melting (SLM) and underwent mechanical and in vitro biological testing. Our results indicate that optimal gradient structures should possess small pores in their core (~900 µm) to increase their mechanical strength whilst large pores (~1100 µm) should be utilized in their outer surface to enhance cell penetration and proliferation. We suggest this approach could be widely used in the design of orthopedic implants to maximize both the mechanical and biological properties of the implant.

Original languageEnglish
Article number200
Number of pages21
JournalMetals
Volume8
Issue number4
DOIs
Publication statusPublished - 1 Apr 2018

Keywords

  • Gradient structure
  • Mechanical properties
  • Osteoblast
  • Porous biomaterial
  • Selective laser melting
  • TI6AL4V

Cite this

@article{58e749f3cfd5469b816997d3d864c8ac,
title = "Mechanical properties and in vitro behavior of additively manufactured and functionally graded Ti6Al4V porous scaffolds",
abstract = "Functionally graded lattice structures produced by additive manufacturing are promising for bone tissue engineering. Spatial variations in their porosity are reported to vary the stiffness and make it comparable to cortical or trabecular bone. However, the interplay between the mechanical properties and biological response of functionally graded lattices is less clear. Here we show that by designing continuous gradient structures and studying their mechanical and biological properties simultaneously, orthopedic implant design can be improved and guidelines can be established. Our continuous gradient structures were generated by gradually changing the strut diameter of a body centered cubic (BCC) unit cell. This approach enables a smooth transition between unit cell layers and minimizes the effect of stress discontinuity within the scaffold. Scaffolds were fabricated using selective laser melting (SLM) and underwent mechanical and in vitro biological testing. Our results indicate that optimal gradient structures should possess small pores in their core (~900 µm) to increase their mechanical strength whilst large pores (~1100 µm) should be utilized in their outer surface to enhance cell penetration and proliferation. We suggest this approach could be widely used in the design of orthopedic implants to maximize both the mechanical and biological properties of the implant.",
keywords = "Gradient structure, Mechanical properties, Osteoblast, Porous biomaterial, Selective laser melting, TI6AL4V",
author = "Ezgi Onal and Frith, {Jessica E.} and Marten Jurg and Xinhua Wu and Andrey Molotnikov",
year = "2018",
month = "4",
day = "1",
doi = "10.3390/met8040200",
language = "English",
volume = "8",
journal = "Metals",
issn = "2075-4701",
publisher = "MDPI",
number = "4",

}

Mechanical properties and in vitro behavior of additively manufactured and functionally graded Ti6Al4V porous scaffolds. / Onal, Ezgi; Frith, Jessica E.; Jurg, Marten; Wu, Xinhua; Molotnikov, Andrey.

In: Metals, Vol. 8, No. 4, 200, 01.04.2018.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Mechanical properties and in vitro behavior of additively manufactured and functionally graded Ti6Al4V porous scaffolds

AU - Onal, Ezgi

AU - Frith, Jessica E.

AU - Jurg, Marten

AU - Wu, Xinhua

AU - Molotnikov, Andrey

PY - 2018/4/1

Y1 - 2018/4/1

N2 - Functionally graded lattice structures produced by additive manufacturing are promising for bone tissue engineering. Spatial variations in their porosity are reported to vary the stiffness and make it comparable to cortical or trabecular bone. However, the interplay between the mechanical properties and biological response of functionally graded lattices is less clear. Here we show that by designing continuous gradient structures and studying their mechanical and biological properties simultaneously, orthopedic implant design can be improved and guidelines can be established. Our continuous gradient structures were generated by gradually changing the strut diameter of a body centered cubic (BCC) unit cell. This approach enables a smooth transition between unit cell layers and minimizes the effect of stress discontinuity within the scaffold. Scaffolds were fabricated using selective laser melting (SLM) and underwent mechanical and in vitro biological testing. Our results indicate that optimal gradient structures should possess small pores in their core (~900 µm) to increase their mechanical strength whilst large pores (~1100 µm) should be utilized in their outer surface to enhance cell penetration and proliferation. We suggest this approach could be widely used in the design of orthopedic implants to maximize both the mechanical and biological properties of the implant.

AB - Functionally graded lattice structures produced by additive manufacturing are promising for bone tissue engineering. Spatial variations in their porosity are reported to vary the stiffness and make it comparable to cortical or trabecular bone. However, the interplay between the mechanical properties and biological response of functionally graded lattices is less clear. Here we show that by designing continuous gradient structures and studying their mechanical and biological properties simultaneously, orthopedic implant design can be improved and guidelines can be established. Our continuous gradient structures were generated by gradually changing the strut diameter of a body centered cubic (BCC) unit cell. This approach enables a smooth transition between unit cell layers and minimizes the effect of stress discontinuity within the scaffold. Scaffolds were fabricated using selective laser melting (SLM) and underwent mechanical and in vitro biological testing. Our results indicate that optimal gradient structures should possess small pores in their core (~900 µm) to increase their mechanical strength whilst large pores (~1100 µm) should be utilized in their outer surface to enhance cell penetration and proliferation. We suggest this approach could be widely used in the design of orthopedic implants to maximize both the mechanical and biological properties of the implant.

KW - Gradient structure

KW - Mechanical properties

KW - Osteoblast

KW - Porous biomaterial

KW - Selective laser melting

KW - TI6AL4V

UR - http://www.scopus.com/inward/record.url?scp=85044770380&partnerID=8YFLogxK

U2 - 10.3390/met8040200

DO - 10.3390/met8040200

M3 - Article

VL - 8

JO - Metals

JF - Metals

SN - 2075-4701

IS - 4

M1 - 200

ER -