EVALUATION OF MECHANOBIOLOGICAL POTENTIAL OF 3D-PRINTED PLA BONE TISSUE SCAFFOLDS WITH DIFFERENT PORE ARCHITECTURES AND POROSITY RATIOS

Lattice structures are widely used in bone tissue scaffold designs due to interconnected porous structures that mimic the natural extracellular matrix (ECM) to treat large bone defects. This study investigated the mechanical behavior of scaffolds with different pore architectures and porosity ratios using experimental and numerical methods. In addition, mechanobiological potentials of scaffolds were evaluated in terms of the specific energy absorption and the specific surface area. Three different geometries were created by varying the combination of vertical, horizontal, and diagonal struts to evaluate the geometric factor and 50%, 62.5, and 75% porosity ratios are examined as potential permeabilities. Compression tests were performed to calculate stiffness values and energy absorptions of the scaffolds. Finite element simulations were used to obtain stiffness values of scaffolds. The specific energy absorptions of scaffolds were calculated under 4 N compressive load as a representative of potential body loads. According to the results, it was found that pore architectures and porosity ratios had crucial effects on stiffness values, energy absorption levels, specific energy absorption, and specific surface area which may lead to significant differences in bone remodeling. The highest specific energy absorption was observed in the scaffolds designed with only diagonal struts with 75% porosity. The highest specific surface area was observed in the scaffolds designed with the combination of vertical, horizontal, and diagonal struts with 75% porosity.