Development of three-dimensional printing polymer-ceramic scaffolds with enhanced compressive properties and tuneable resorption

Zhou, Zuoxin; Cunningham, Eoin; Lennon, Alex; McCarthy, Helen O.; Buchanan, Fraser; Dunne, Nicholas

Abstract

In this study, bone tissue engineered scaffolds fabricated via powder-based 3D printing from hydroxyapatite (HA) and calcium sulphate (CaSO4) powders were investigated. The combination of using a fast resorbing CaSO4 based powder and the relatively slower HA powder represents a promising prospect for tuning the bioresorption of 3D printed (3DP) scaffolds. These properties could then be tailored to coincide with tissue growth rate for different surgical procedures. The manufactured scaffolds were infiltrated with poly(??caprolactone) (PCL). The PCL infiltrated the inter-particle spacing within the 3DP structures due to the nature of a loosely-packed powder bed and also covered the surface of ceramic-based scaffolds. Consequently, the average compressive strength, compressive modulus and toughness increased by 314%, 465% and 867%, respectively. The resorption behaviour of the 3DP scaffolds was characterised in vitro using a high-throughput system that mimicked the physiological environment and dynamic flow conditions relevant to the human body. A rapid release of CaSO4 between Day 0 and 28 was commensurate with a reduction in scaffold mass and compressive properties, as well as an increase in medium absorption. In spite of this, HA particles, connected by PCL fibrils, remained within the microstructure after 56?days resorption under dynamic conditions. Consequently, a high level of structural integrity was maintained within the 3DP scaffold. This study presented a porous PCL-HA-CaSO4 3DP structure with the potential to encourage new tissue growth during the initial stages of implantation and also offering sufficient structural and mechanical support during the bone healing phase.

Citation

Zhou, Z., Cunningham, E., Lennon, A., McCarthy, H. O., Buchanan, F., & Dunne, N. (2018). Development of three-dimensional printing polymer-ceramic scaffolds with enhanced compressive properties and tuneable resorption. Materials Science and Engineering: C, 93, 975-986. doi:10.1016/j.msec.2018.08.048

• Journal Article Type: Article
• Acceptance Date: Aug 21, 2018
• Online Publication Date: Aug 23, 2018
• Publication Date: Nov 1, 2018
• Deposit Date: Oct 24, 2018
• Publicly Available Date: Aug 24, 2019
• Journal: Materials Science and Engineering: C
• Print ISSN: 0928-4931
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 93
• Pages: 975-986
• DOI: https://doi.org/10.1016/j.msec.2018.08.048
• Keywords: Mechanical Engineering; General Materials Science; Mechanics of Materials; Condensed Matter Physics
• Public URL: https://nottingham-repository.worktribe.com/output/1186472
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0928493117338110
• Additional Information: This article is maintained by: Elsevier; Article Title: Development of three-dimensional printing polymer-ceramic scaffolds with enhanced compressive properties and tuneable resorption; Journal Title: Materials Science and Engineering: C; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.msec.2018.08.048; Content Type: article; Copyright: Crown Copyright © 2018 Published by Elsevier B.V. All rights reserved.