Curvature Controlled Tissue Growth in Bio-Degradable Bone Scaffold Optimization

Background: Biodegradable bone scaffolds are an emerging topic in the field of tissue engineering. Stem cells are cultured upon a 3D printed scaffold and differentiated into bone tissue. The scaffold is then implanted into a patient where a new bone forms around the degrading polymer, leaving a newly grown bone. The goal is to construct a scaffold design maximizing the cell growth rate within the structure. This is achieved by controlling geometric parameters, like the thickness of the filaments constituting the scaffold.

Methods: There are several factors known to affect the mechanical integrity and cell growth within the scaffold. Two vital factors are the substrate shape and pore size. A computational 3D Curvature Controlled Tissue Growth (CCTG) algorithm is proposed to study the effects of these factors. It simulates the motion of the interface between cells and culture-fluid.

Results: The numerical results describe local cell movement and tissue growth rates, showing sound agreement with previous 2D and 3D experiments. The CCTG algorithm was implemented iteratively to solve a design optimization problem, to maximize cell growth rates under given feasibility constraints. Two methods that were used, a greedy search and a genetic algorithm, were in good correspondence.

Conclusion: As in other fields of study, simulation and optimization methods prove as potent design tools for tissue engineering. A platform suitable for multi-aspect optimization is presented, providing a springboard for a more comprehensive design of bone scaffolds.