Tetrahedron-Based Porous Scaffold Design for 3D Printing

Abstract

Tissue repairing has been the ultimate goal of surgery, especially with the emergence of reconstructive medicine. A large amount of research devoted to exploring innovative porous scaffold designs, including homogeneous and inhomogeneous ones, have been presented in the literature. The triply periodic minimal surface has been a versatile source of biomorphic structure design due to its smooth surface and high interconnectivity. Nonetheless, many 3D models are often rendered in the form of triangular meshes for its efficiency and convenience. The requirement of regular hexahedral meshes then becomes one of limitations of the triply periodic minimal surface method. In this paper, we make a successful attempt to generate microscopic pore structures using tetrahedral implicit surfaces. To replace the conventional Cartesian coordinates, a new coordinates system is built based on the perpendicular distances between a point and the tetrahedral faces to capture the periodicity of a tetrahedral implicit surface. Similarly to the triply periodic minimal surface, a variety of tetrahedral implicit surfaces, including P-, D-, and G-surfaces are defined by combinations of trigonometric functions. We further compare triply periodic minimal surfaces with tetrahedral implicit surfaces in terms of shape, porosity, and mean curvature to discuss the similarities and differences of the two surfaces. An example of femur scaffold construction is provided to demonstrate the detailed process of modeling porous architectures using the tetrahedral implicit surface.

TPMS-based membrane lung with locally-modified permeabilities for optimal flow distribution

“…Moreover, methods for defining novel TPMS are the subject of ongoing research. Implicit surface modeling methods enabled the creation of minimal surfaces which were not periodic in the Cartesian coordinate system but rather in a tetrahedral coordinate system and have proven more reliable in replicating complex structures without the need for complex mapping techniques 40 . Such surfaces could provide benefits when designing modules that do not conform to highly-regular geometries like those used in modern oxygenators, possibly even taking the contours of natural organs into account 41 .…”

Design and Analysis of Biomedical Scaffolds Using TPMS-Based Porous Structures Inspired from Additive Manufacturing

“…For treating large SBD, TPMS-based porous scaffolds are designed and mapped on the solid bone model using Boolean operations, resulting in a porous scaffold structure, ensuring application at various anatomical sites for bridging bone gaps [74][75][76][77]. The bone mapping method is patient-specific, and the customized modeling methodology demonstrates the efficacy of the design criterion to develop a proficient bone scaffold architecture for generating patient-specific implants with adequate mechanical characteristics [74,[78][79][80].…”

Design and Applications of Additive Manufacturing and 3D Printing

“…Topology optimization and laser-based powder bed fusion additive manufacturing were utilized by Orne et al [13] to develop space flight hardware. They redesigned and manufactured two heritage parts for a Surrey Satellite Technology LTD (SSTL) Technology Demonstrator Space Mission and a system of five components for SpaceIL's lunar launch vehicle.…”