Geometry-Based Computational Fluid Dynamic Model for Predicting the Biological Behavior of Bone Tissue Engineering Scaffolds

Abstract

The use of biocompatible and biodegradable porous scaffolds produced via additive manufacturing is one of the most common approaches in tissue engineering. The geometric design of tissue engineering scaffolds (e.g., pore size, pore shape, and pore distribution) has a significant impact on their biological behavior. Fluid flow dynamics are important for understanding blood flow through a porous structure, as they determine the transport of nutrients and oxygen to cells and the flushing of toxic waste. The aim of this study is to investigate the impact of the scaffold architecture, pore size and distribution on its biological performance using Computational Fluid Dynamics (CFD). Different blood flow velocities (BFV) induce wall shear stresses (WSS) on cells. WSS values above 30 mPa are detrimental to their growth. In this study, two scaffold designs were considered: rectangular scaffolds with uniform square pores (300, 350, and 450 µm), and anatomically designed circular scaffolds with a bone-like structure and pore size gradient (476–979 µm). The anatomically designed scaffolds provided the best fluid flow conditions, suggesting a 24.21% improvement in the biological performance compared to the rectangular scaffolds. The numerical observations are aligned with those of previously reported biological studies.

Bamboo-Inspired Porous Scaffolds for Advanced Orthopedic Implants: Design, Mechanical Properties, and Fluid Characteristics

“…The findings demonstrate that when β is 2/3, the proportion of high WSS (>0.03 Pa) is minimal, comprising only 0.45%. Previous experimental findings have indicated that cell proliferation and differentiation were favored when the WSS remains below 0.01 Pa at lower levels , and a WSS <0.03 Pa correlates with enhanced osteoblast differentiation . Considering the BISs’ favorable characteristics in terms of flow velocity distribution, permeability, and WSS, it emerges as an ideal choice for a porous orthopedic implant, but further biological experiments are still needed to verify it.…”

Computational fluid dynamics study on three‐dimensional polymeric scaffolds to predict wall shear stress using machine learning models for bone tissue engineering applications

“…Analysis of WSS distribution on each scaffold is quantified by measuring the surfaceaverage WSS, which is more accurate than the volume average followed in the previous work. 12 The total number of surfaces for each design of scaffold differs and ranges from 64 to 96. Surface-averaged WSS was calculated by multiplying the velocity gradient with the viscosity of the body fluid in each selected surface by installing a virtual probe.…”

“…Biologically designed scaffolds have uniform pore sizes and complex architecture. 12 Machine learning (ML) algorithms have been applied to these CFD simulations to accelerate the design process, to reduce computational time and cost, and also to improve the accuracy of the results. The application of deep learning (DL) models, such as convolutional neural networks (CNNs) and recurrent neural networks (RNNs), to CFD simulations in tissue engineering has been increasingly utilized in recent years.…”

“…Laminar flow CFD studies investigated on biologically designed scaffolds show improved biological behavior than rectangular scaffolds. Biologically designed scaffolds have uniform pore sizes and complex architecture 12 …”

Micronesian maritime piloting charts as bioimaging proxies for the rescue of cells on the apoptotic trajectory

“…The last few decades in tissue engineering have seen a disproportionate focus on the studies of control of cell fate through the control of properties of solid materials onto which the cells adhere, ranging from the chemical composition [ 4 ] to topography [ 5 ] to mechanical stiffness [ 6 ], leaving the hydrodynamic effects of the fluid medium on the cells understudied in comparison. It is known, however, that the dynamics of the fluid flow through three-dimensional scaffolds has a critical effect on the fate of cells seeded inside them [ 7 ] and that structures of the cellular junctions and cytoskeleton can be altered by controlling fluid flow regimens inside the cerebral microvasculature [ 8 ], likely affecting consciousness and cognition [ 9 ]. Therefore, it is clear that the investigation of the relationship between cell behavior and hydrodynamic properties of the medium in which they grow should be more copious than it is today.…”