Assessment of Cellular Responses in Non-Twisted and Twisted Scaffolds Using a Multiscale Computational Approach

In bone tissue engineering (BTE), suitable mechanical stimulation is required to support cellular activities during bone regeneration. Now, the implanted BTE scaffolds keep deforming and are subjected to physiological loading, which influences the fluid flow within the scaffold and surrounding tissue. Hence, understanding the mechanobiological changes of a bone cell seeded on the deformed scaffold needs to be specially focused. Therefore, twisted and non-twisted face-centered cubic scaffolds were modeled for identifying the changes in cellular mechanical stimulation at different locations of a scaffold. At first, a global computational fluid dynamics (CFD) study was conducted to predict the permeability and fluid shear stress (FSS) of the scaffold; further CFD-induced pressure data was applied to the sub-scaffold finite element model to predict the mechanical responses of osteoblasts placed in different positions of the twisted and non-twisted scaffolds. The results indicated a decline in permeability as twist angles increased. While mechanobiological stimulation within the scaffold improved up to a certain twist angle, exceeding this threshold may reduce the effectiveness of mechanical stimulation. These findings could help determine the influence of twisting, identify the optimal twist angle, and also guide the selection of ideal areas for cell placement within the scaffold to enhance bone regeneration.