Strategies for the design of additively manufactured nanocomposite scaffolds for hard tissue regeneration

Pierpaolo Fucile,Ilaria Onofrio,Roberto De Santis,Vito Gallicchio,Antonio Gloria,Andrea Rega,Teresa Russo,Giovanni Improta,Ida Papallo,Vincenzo D'Antò

doi:10.21014/acta_imeko.v9i4.739

Abstract

Additive manufacturing represents a powerful tool for the direct fabrication of lightweight and porous structures with tuneable properties. In this study, a fused deposition modelling/3D fibre deposition technique was considered for designing 3D nanocomposite scaffolds with specific architectures and tailored biological, mechanical, and mass transport properties. 3D poly(caprolactone) (PCL)/hydroxyapatite (HA) nanocomposite scaffolds were designed for bone tissue engineering. An optimisation design strategy for the additive manufacturing processes based on extrusion/injection methods was at first extended to the development of the PCL/HA scaffolds. Further insight into the effect of the process parameters on the mechanical properties and morphological features of the nanocomposite scaffolds was provided. The nanocomposite structures were analysed at different levels, and the possibility of designing 3D customised scaffolds for mandibular defect regeneration (i.e., symphysis and ramus) was also reported.

Highlights

Bone is capable of healing and remodelling itself except in the case of defects that exceed a critical size [1], [2]
The manufacturing parameters were selected to obtain a value of the road width (RW) that was equivalent to the inner nozzle diameter (400 μm), attempting to reduce the fabrication time and to maintain the highest reproducibility without significant alteration of the structural stability of the devices
Differences in terms of the RW and porosity were observed at different process temperature (PT) values, the results suggested that both the compressive modulus and the maximum stress were not greatly affected if the PT was increased above 120 °C

Summary

Introduction

Bone is capable of healing and remodelling itself except in the case of defects that exceed a critical size [1], [2]. Even though it is reported that there is no risk of device rejection or disease transmission, many complications arise due to poor availability, prolonged hospitalisation, donor-site morbidity and pain, and high risk of infection and haematoma [1]-[3]. For this reason, allografts may be seen as an alternative to autografts but their clinical applications are strongly limited by the risk of pathogenic disease transmission as well as low integration with native tissues [4]-[9]. The use of metallic devices may lead to the risk of bone resorption and fracture as a consequence of the low torsion of the great mismatch between the mechanical properties of the implant and the bone

Methods

Results

Conclusion