3D-printed biodegradable gyroid scaffolds for tissue engineering applications

Abstract

Fused deposition modeling (FDM), a low cost and easy-to-use additive manufacturing technique, was pushed to its typical resolution limit to produce poly(lactic acid) (PLA) gyroid scaffolds. A gyroid morphology was selected as scaffold structure due to its spring shape architecture, high porosity, leading to good nutrient and waste diffusion, and favorable mechanical properties, such as isotropic resistance to pressure. Printing parameters were optimized and the need of a support material to improve printing quality was evidenced. The gyroid structure was compared with the more common strut-based structure. Scaffold porosity was measured by micro-CT, and mechanical properties were determined by compressive mechanical tests. The effect of mesh geometry, printing resolution, and PLA crystallinity on resistance against compression was evaluated. Moreover, the impact of PLA scaffold geometry and crystallinity on its degradation was studied in vitro. Porosity of the gyroid structure was 71%, close to the 74% expected from the model used for printing. The compression tests showed that the gyroid scaffold has an isotropic behavior, in contrast with the typical strut-based scaffold, which exhibits an orientation-dependent deformation. Upon aging in physiological conditions, gyroid scaffolds retained their integrity during 64 weeks, while control scaffolds lost struts one after the other starting from week 33, in a way that depended on crystallinity and printing resolution. For both geometries, the remaining mass started to decrease at week 52. Based on these results, the gyroid design is proposed as a suitable mesh architecture for tissue engineering scaffolds that can be elaborated using FDM techniques, to produce low cost and personalized implants.

On the Use of Surfactant‐Complexed Chitosan for Toughening 3D Printed Polymethacrylate Composites

“…Gyroid was selected because of its mesh structure suitable for robust 3D printed scaffolds in tissue engineering applications. [ 70 ] The printed gyroid structure at 8 wt% SMCS loading is found to be comparable with that of commercial PMA resin (0 wt% SMCS) in terms of the details and the quality of the design (Figure 8a,b). Likewise, the dimensional accuracy was then evaluated by 3D reconstruction and surface measurement of a 3D‐printed bolt with 8 wt% SMCS loading (Figure 8c,d).…”

Flexural Properties and Fracture Behavior of CF/PEEK in Orthogonal Building Orientation by FDM: Microstructure and Mechanism

“…In order to further understand the mechanical behavior of the printed samples, it was essential to determine their porosity and pore distribution. In recent years, X-ray μ-CT has proven to be a useful tool for medical diagnoses and nondestructive ultrasonic detection of 3D printed samples [29]. The orthogonally printed flexural specimens before and after bending tests were scanned via X-ray μ-CT. From the results, we can see that the porosity of the two orthogonally printed CF/PEEK composites were larger than that of PEEK.…”

Favorable Thermoresponsive Shape Memory Effects of 3D Printed Poly(Lactic Acid)/Poly(ε‐Caprolactone) Blends Fabricated by Fused Deposition Modeling

“…[4] Among the available 3D printing technologies, fused deposition modeling (FDM) is the most commonly used and cost-effective. [5,6] However, the printing materials suitable for FDM are generally limited to thermoplastics. The printing anisotropy and printing orientation in FDM process attracted great interest.…”