Combined X-ray and neutron tomography for simultaneous assessment of in silico mechanical response and in vitro biological behavior of graded scaffolds: a preliminary study

This study presents a pioneering approach combining X-ray Computed Tomography (XCT) and Neutron Computed Tomography (NCT) to simultaneously assess the biomechanical and biological behavior of bone scaffolds fabricated by additive manufacturing. XCT was employed to model post-fabrication scaffold geometry, enabling precise finite element (FE) predictions on how each defect type, such as strut densification, lack of fusion and porosity, impacts the overall mechanical performance of the scaffold. Defect-inclusive models were successfully validated against experimental data. NCT was instead concomitantly used to assess short-term changes in the behavior of MG-63 human osteoblast-like cells under different culture conditions. Quantitative analysis of NCT scans of our samples showed that neutrons, thanks to their sensitivity to organic material, are able to discriminate between different compositions of the organic material itself. This research not only provides a comprehensive framework for preclinical characterization of scaffolds, but also paves the way for more efficient evaluation of implantable devices, ultimately reducing the reliance on animal models in biomaterials research.