Topological, Mechanical and Biological Properties of Ti6Al4V Scaffolds for Bone Tissue Regeneration Fabricated with Reused Powders via Electron Beam Melting.

Maria Laura Gatto,Lorenzo Fassina,Nora Bloise,Paolo Mengucci,Manuela Galati,Riccardo Groppo,Livia Visai,Luca Iuliano

doi:10.3390/ma14010224

Abstract

Cellularized scaffold is emerging as the preferred solution for tissue regeneration and restoration of damaged functionalities. However, the high cost of preclinical studies creates a gap between investigation and the device market for the biomedical industry. In this work, bone-tailored scaffolds based on the Ti6Al4V alloy manufactured by electron beam melting (EBM) technology with reused powder were investigated, aiming to overcome issues connected to the high cost of preclinical studies. Two different elementary unit cell scaffold geometries, namely diamond (DO) and rhombic dodecahedron (RD), were adopted, while surface functionalization was performed by coating scaffolds with single layers of polycaprolactone (PCL) or with mixture of polycaprolactone and 20 wt.% hydroxyapatite (PCL/HA). The mechanical and biological performances of the produced scaffolds were investigated, and the results were compared to software simulation and experimental evidence available in literature. Good mechanical properties and a favorable environment for cell growth were obtained for all combinations of scaffold geometry and surface functionalization. In conclusion, powder recycling provides a viable practice for the biomedical industry to strongly reduce preclinical costs without altering biomechanical performance.

Highlights

An approach to bone tissue regeneration based on cellularized-scaffold implantation was used to overcome the risks connected to bone grafts when self-healing fails [1].The focal point of scaffolds for bone tissue regeneration is unit cell topology which influences mechanical and biological performance [1]
Both these features relate to porosity, pore size and pore interconnectivity, that in turn are determined by scaffold elementary unit cell geometry
The results summarized for the mass struts; VTiaccording

Summary

Introduction

The focal point of scaffolds for bone tissue regeneration is unit cell topology which influences mechanical and biological performance [1]. Suitable mechanical properties are required in load-bearing applications while suitable mass transport properties are necessary for biological activities [2]. Both these features relate to porosity, pore size and pore interconnectivity, that in turn are determined by scaffold elementary unit cell geometry. Numerical analysis by computational fluid dynamics (CFD) [6] has demonstrated that DO shows advantages in implant fixation (greater tortuosity and larger aperture), cell growth environment (more appropriate adhesion areas), and tissue regeneration (due to regular mechanical stimulation), while RD shows a superior mass transport performance (higher flow velocity value). DO and RD elementary unit cells are valid alternatives for bone tissue regeneration

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