EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Scaffolds are a necessary tool for the clinical treatment of critical sized bone defects. Additive manufacturing offers the potential to produce personalized porous scaffolds for such tissue engineering applications with unprecedented control of structural and functional design. Particularly for bone defect regeneration, the complex coupling of biological mechanisms to the scaffolds' mechanical properties has led to a predominantly trial-and-error approach for harnessing this design freedom. The most conventional approach that is currently in development for polymer based bone scaffolds is a raster-angle design.

As a first step in this work, we present an approach based on triply periodic minimal surface (TPMS) architectures. TPMS for bone scaffold designs are partially inspired by their resemblance to trabecular bone, which is particularly noticeable for the gyroid. As it turns out, these TPMS-based designs do exhibit advantageous mechanical properties compared to raster-angle designs.

TPMS geometries also arise as results in certain shape optimization problems. In the second step of this work, we thus consider a domain-splitting shape optimization problem related to bone regeneration in the presence of scaffolds and discuss the resulting optimized scaffold designs.

Finally, we will present an approach to optimize the local porosity of additively manufactured scaffolds for bone tissue engineering applications using a mathematical model for bone regeneration depending on the given scaffold parameters. Together, these optimization approaches may lead to patient specific custom bone scaffold designs in the sense of 'precision medicine', taking into account defect geometry, expected mechanical loading, individual patients' regenerative capacity, and comorbidities.