Fabrication of bone tissue engineering scaffolds with a hierarchical structure using combination of 3D printing/gas foaming techniques

The goal of this research was to study and optimize the structure and geometric features of scaffolds made using a combined method of 3D printing and gas foaming. This endeavor aimed to produce scaffolds with a hierarchical structure that closely resemble bone tissue. The study examined the effects of saturation pressure, foam temperature, and foam time on the scaffolds using response surface methodology (RSM). RSM is statistical technique used for optimizing and analyzing processes by modeling relationship between input variables and output responses. The results of multi‐objective optimization showed that highest pressure (55 MPa), the shortest time (40 s), and the temperature of 68°C were the optimal conditions. RSM was also used to develop mathematical models of structural properties, dimensional accuracy, and mechanical strength, focusing on different foam parameters, which could be used to predict desired properties. Subsequently, the designed scaffold underwent MTT assay testing to assess cell toxicity indicating its biocompatibility. The results demonstrate that by using the correct foam parameters in combination with 3D printing, it is possible to achieve polymer scaffolds with proportional dimensions, geometry, and mechanical strength suitable for cell growth to use inside the human body. Cellular structure of rasters of 3d printed PLA filaments.