Characterization of Mechanical Properties of Tissue Scaffolds by Phase Contrast Imaging and Finite Element Modeling

Abstract

In tissue engineering, the cell and scaffold approach has shown promise as a treatment to regenerate diseased and/or damaged tissue. In this treatment, an artificial construct (scaffold) is seeded with cells, which organize and proliferate into new tissue. The scaffold itself biodegrades with time, leaving behind only newly formed tissue. The degradation qualities of the scaffold are critical during the treatment period, since the change in the mechanical properties of the scaffold with time can influence cell behavior. To observe in time the scaffold's mechanical properties, a straightforward method is to deform the scaffold and then characterize scaffold deflection accordingly. However, experimentally observing the scaffold deflection is challenging. This paper presents a novel study on characterization of mechanical properties of scaffolds by phase contrast imaging and finite element modeling, which specifically includes scaffold fabrication, scaffold imaging, image analysis, and finite elements (FEs) modeling of the scaffold mechanical properties. The innovation of the work rests on the use of in-line phase contrast X-ray imaging at 20 KeV to characterize tissue scaffold deformation caused by ultrasound radiation forces and the use of the Fourier transform to identify movement. Once deformation has been determined experimentally, it is then compared with the predictions given by the forward solution of a finite element model. A consideration of the number of separate loading conditions necessary to uniquely identify the material properties of transversely isotropic and fully orthotropic scaffolds is also presented, along with the use of an FE as a form of regularization.

Effect of Nanoparticle Incorporation and Surface Coating on Mechanical Properties of Bone Scaffolds: A Brief Review

“…It is expected that the mechanical properties of a scaffold match with the ones of the native tissue to be repaired [ 1 , 2 ]. Toward this end, it is imperative to characterize the mechanical properties of scaffolds after their fabrication and before their implantation to ensure the appropriate performance [ 2 , 3 , 4 , 5 , 6 , 7 ]; otherwise, the implanted scaffold may not be succeeding in the following repair process.…”

Modeling of the Mechanical Behavior of 3D Bioplotted Scaffolds Considering the Penetration in Interlocked Strands

“…It should also be noted that degradation of the scaffold over time can affect the mechanical properties of scaffolds and in this regard, many studies have been made to predict the mechanical behavior of scaffolds considering the effect of degradation in physiological condition [38][39][40]. In this study, we focused on the effect of penetration without the consideration of scaffold degradation over time.…”

Modeling of the Mechanical Behavior of 3D Bioplotted Scaffolds Considering the Penetration in Interlocked Strands

“…Figure 8 shows the effect of each factor on the elastic modulus demonstrating the significant effect of different terms on the elastic modulus. It should also be noted that degradation of the scaffold over time can affect the mechanical properties of scaffolds and in this regard, many studies have been made to predict the mechanical behavior of scaffolds considering the effect of degradation in physiological condition [38][39][40]. In this study, we focused on the effect of penetration without the consideration of scaffold degradation over time.…”