Design, Stereolithographic 3D Printing, and Characterization of TPMS Scaffolds

Abstract

Anatomical and functional tissue loss is one of the most debilitating problems and involves a great cost to the international health-care sector. In the field of bone tissue, the use of scaffolds to promote tissue regeneration is a topic of great interest. In this study, a combination of additive manufacturing and computational methods led to creating porous scaffolds with complex microstructure and mechanical behavior comparable to those of cancellous bone. Specifically, some representative models of triply periodic minimal surfaces (TPMSs) were 3D-printed through a stereolithographic technique using a dental resin. Schwarz primitive and gyroid surfaces were created computationally: they are characterized by a complex geometry and a high pore interconnectivity, which play a key role in the mechanism of cell proliferation. Several design parameters can be varied in these structures that can affect the performance of the scaffold: for example, the larger the wall thickness, the lower the elastic modulus and compressive strength. Morphological and mechanical analyses were performed to experimentally assess the properties of the scaffolds. The relationship between relative density and elastic modulus has been analyzed by applying different models, and a power-law equation was found suitable to describe the trend in both structures.

Numerical Study of Fluid Flow in a Gyroid-Shaped Heat Transfer Element

“…Gabrieli et al [20] addressed 3D printing using stereolithographic techniques to create triply periodic minimal surfaces in the form of Schwarz P and gyroid. Although the authors did not use thermally conductive material, the methods employed yielded highly accurate products.…”

“…Despite their apparent complexity, they have the potential to transform various branches of science and technology and lead to the discovery of new materials and technologies with revolutionary potential. Some of the best-known examples include the gyroid, Schwarz P, Schwarz D (see Figure 1), and many others, each with its own unique symmetries and properties [20]. The second principle that has been applied in the creation of the described geometry is the creation of a three-dimensional solid using a recursive function.…”

Novel 3D printed TPMS scaffolds: microstructure, characteristics and applications in bone regeneration

“… 8 TPMS scaffolds are constructed of continuous surface structures with optimised fluid permeability, and they exhibit open cell networks that provide continuous porosity for vascularisation and highly interconnected pores that provide sufficient space for cell attachment, promoting cell adhesion and retention. 92 Wall shear stress (WSS) generated by fluid flow within the scaffold is an important factor to consider because it affects cell distribution during new tissue formation. The WSS is caused by the relative motion between the wall of the support and fluid in the support.…”