Additive Manufacturing of TPMS Structures in Tricalcium Phosphate and Phosphate-Based Glass for Bone Tissue Engineering

Bone tissue has the ability of remodelling and allow the repair of little damages and adapt to mechanical stress experienced. This process is not possible with certain diseases like osteoporosis or bone cancer, and the necessity of bone grafting occurs. The higher demand, primarily due to the progressive aging of population, makes transplantation a limited option; the solution can be found in bone tissue engineering, that is studying and developing synthetic bone substitutes, created using biocompatible and bioactive materials, primarily bioceramics, that promote bone regeneration. These materials can be processed into scaffolds—structures that act as support for cells— using 3D printing techniques. In this thesis, Triply Periodic Minimal Surfaces (TPMS) structures were analyzed. These are complex structures that are highly useful for scaffold production due to their fundamental properties, including advantageous topological characteristics and good mechanical performance. Scaffolds were manufactured using the Digital Light Processing (DLP) additive manufacturing technique, focusing on two structures: Primitive and Neovius. The scaffolds were printed using two different materials: ß-Tricalcium Phosphate (ß-TCP) and a phosphate-based bioactive glass, and then heat treated. The heat treatment was followed by mechanical compression tests, geometrical analysis and density evaluations to assess the quality of the printing, mechanical resistance, and scaffold porosity. The Neovius structure consistently demonstrated superior mechanical strength, while the Primitive structure provided higher levels of porosity. The aim of the work was to obtain scaffolds with different characteristics and to analyze them in order to evaluate which of these structures and materials can create an efficient combination that can be a suitable scaffold for bone tissue engineering, where the adhesion and proliferation of bone cells are supported.