3D Microtomographic Characterization of Precision Fused Deposited Biocompatible Polymer Scaffolds

A. Darling and W. Sun
Summary of the Awarded Paper

One of the dominant approaches to tissue engineering is the seeding of biodegradable biocompatible polymer scaffolds with progenitor cells prior to 3D culture or implantation. The microarchitecture of these scaffolds has direct effects upon the ability of cells to attach, migrate, and thrive. Microtomographic (micro-CT) scanners enable high-speed 3D characterisation of the salient features of these polymer scaffolds. A micro-CT scan followed by 3D reconstruction of serial image sections can determine porosity, pore size, pore interconnectivity, strut size and 3D microarchitecture. In this study, four polycaprolactone (PCL) samples with different microarchitectures were manufactured through fused deposition free-form fabrication and subsequently characterised through micro-CT analysis. A desktop micro-CT scanner was used to examine each sample at approximately 19.1-micron resolution. 2D analyses and 3D reconstructions of core regions of each sample were performed. All samples showed greater than 98% pore interconnectivity and predictable pore sizes in the range of 200 to 300 microns. The widths of the individual polymer struts were consistent in all samples, indicating a capacity to build samples of controlled porosity simply through manipulating the spacing of the struts. These results also illustrate that qualitative and quantitative analysis of polymer scaffolds is possible using micro-CT and 3D reconstruction techniques.