Computed Tomography-Driven Design and Fused Filament Fabrication of Graded Density Bone Scaffolds
Source abstract
Abstract
The design of scaffolds and prostheses benefits from the opportunities provided by additive manufacturing technologies. Specifically, scaffold design using cellular structures based on lattices has become a significant focus. These lattice-based scaffolds exhibit intricate and complex shapes with controlled macro-porosity. In this study, a method is presented that enables the modeling of a graded-density lattice structure for material extrusion additive manufacturing, without relying on a geometric lattice model. The methodology utilizes computed tomography (CT) scans as inputs to obtaining a 3D scalar field and a surface model. The lattice structure is designed and generated within the computer-aided manufacturing (CAM) software, ensuring consistent machine toolpaths. The 3D scalar field, representing a relative density map derived from CT Hounsfield units, drives the variation of the extrusion parameters generated by the CAM, achieving a graded-density lattice. To demonstrate the effectiveness of the method, a section of a human femur bone with a lattice with a triply periodic minimal surface (TPMS) gyroid pattern was designed and 3D-printed, replicating the relative density of the target tissue.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Bone Tissue Engineering Materials · Additive Manufacturing and 3D Printing Technologies · Dental materials and restorations
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Civil, Environmental, and Architectural Engineering, University of Padova, Via Venezia 1, 35131 Padova, Italy
Funding
project “GOALS, Green Optimization by Additive-Manufactured Lightweight Structures” · National Recovery and Resilience Plan (NRRP), · European Union—Next-Generation EU
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