Octahedron pore architecture to enhance flexibility of nasal implant-shaped scaffold for rhinoplasty

This study is a part of ongoing research conducted to develop an ideal implant for augmentation rhinoplasty using a combination of cartilage tissue engineering and 3D printing (3DP) techniques. A promising nasal implant-shaped (NIS) scaffold for rhinoplasty should have flexibility similar enough to native cartilage tissue to maintain its mechanical stability after implantation into a nose. In scaffold fabrication using 3DP, the pore pattern or architecture has a significant effect on the mechanical properties of a scaffold. In this study, we proposed octahedron pore architecture inspired by a zigzag spring, which stores more mechanical energy than a simple rod. Therefore, we assumed that the scaffold having octahedron pore architecture is more flexible than one that has the cube or lattice pore architecture that is widely used in tissue engineering based on 3DP. To verify this assumption, scaffolds having octahedron, cube, or lattice pore architecture with the same porosity and same unit cell size were fabricated using projection-based micro-stereolithography and sacrificial molding, and their mechanical behaviors were analyzed using compression and three-point bending tests. Compared to the other pore types, the octahedron pore architecture had superior flexibility, which is beneficial for clinical application of NIS scaffolds.