Fused deposition modeling of biodegradable polymeric scaffolds

No Thumbnail Available

URL

Journal Title

Journal ISSN

Volume Title

School of Electrical Engineering | Master's thesis
Checking the digitized thesis and permission for publishing
Instructions for the author

Date

2012

Major/Subject

Polymeeriteknologia

Mcode

Kem-100

Degree programme

Language

en

Pages

[8] + 100 s. + liitt. 24

Series

Abstract

Three-dimensional printing (3DP) consists of a group of promising additive manufacturing techniques which can be utilized in tissue engineering applications. Fused deposition modelling (FDM) is a less studied 3DP method capable of utilizing thermoplastic common biopolymers. Little attention has been previously paid to examining the suitability of this method to such applications. The purpose of this thesis was to determine the feasibility of FDM to tissue engineering scaffold design and manufacturing. The feasibility was investigated by examining the potential material scope, the mechanical properties of FDM-printed porous structures, and the cell-cultural response to the structures by studying the proliferation on the scaffold surface. This study demonstrated the printability of a poly (epsilon-caprolactone) bioactive glass (PCL/BAG) composite as well as L-lactide/epsilon-caprolactone 75/25 mol-% copolymers for the first time as far as we know. SEM images showed BAG particles at the surface of the printed PCL/BAG scaffolds. The mechanical testing showed the possibility to alter the compressive stiffness of a scaffold matrix without a change in the compressive modulus. A structure with 0°/90° raster angles and vertical pore channels was vertically approximately 60-% stiffer than the structure with 0°/90° raster angles and diagonal pore channels. A structure with 0°/60°/120° raster angles was as stiff vertically compared to the first matrix but horizontally 25-% to 50-% less stiff. The horizontal compressive modules were 12-% to 39-% higher than vertical compressive modules, suggesting strong adhesion between the layers. The proliferation results suggested polylactide (PLA) is superior material over PCL or PCL/BAG -composite for cell growth. The proliferation was three times higher in PLA than in other materials. Bioactive glass evoked no significant additional cell growth compared to pure PCL structures. Light microscope and SEM images showed both the viability and the oriented structure of the cells. The cells were growing in multiple layers, and the biocompatibility of the structures was demonstrated. Finally, a model trachea scaffold with interconnected pores and 40 % porosity was created to show the applicability of FDM for porous scaffold design.

Description

Supervisor

Seppälä, Jukka

Thesis advisor

Korhonen, Harri
Malin, Minna

Keywords

fused deposition modeling, 3D-pikavalmistus, tissue engineering, pursotus, scaffolds, kudosteknologian tukirakenteet, trachea scaffolds, trakean tukirakenteet

Other note

Citation