Comparison of Selective Laser Melted Commercially Pure Titanium Sheet‐Based Triply Periodic Minimal Surfaces and Trabecular‐Like Strut‐Based Scaffolds for Tissue Engineering. Issue 1 (1st October 2021)

• Record Type: Journal Article
• Authors: Torres-Sanchez, Carmen; Borgman, James M.; Sargeant, Ben; Bell, Hugo; Alabort, Enrique; Lindsay, Craig; Conway, Paul P.
• Is Part Of: Advanced engineering materials. Volume 24:Issue 1(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-10-01
• Subjects: commercially pure titanium -- gyroids -- IWP -- osteoblasts -- selective laser melting -- trabecular -- Voronoi tessellations; Materials -- Periodicals; 620.11
• DOI: 10.1002/adem.202100527
• Languages: English
• ISSNs: 1438-1656

Abstract

Abstract : This systematic comparison between sheet‐based triply periodic minimal surfaces (TPMS) and strut‐based ordered and disordered lattice topologies offers insights into parametric designs for tissue engineering scaffolds intended as implants. The study explores the effect of topology on compressive properties and in vitro osteoblastogenesis. TPMS‐sheet gyroid and IWP, Voronoi tessellation with different sharpness, and cubic orthogonal lattices are studied. Disparities between the design intent and the as‐manufactured scaffolds, intrinsic to selective laser processing, are considered to ensure that actual porosity and surface area per unit volume, two important factors in tissue engineering, are consistent across the set. Surface analysis reports the presence of microporosity created by partly sintered titanium particles. The TPMS topologies display a stretching‐dominated deformation and the strut‐based disordered ones a bending‐dominated double‐shear failure. Although the trabecular‐like structures exhibit an enhanced compressive behavior when the designed topology is smoothed, they are more prone to printing imperfections with sharper finishes. The in vitro studies reveal that the trabecular sharp topology displays a faster proliferation rate, explained by concavity‐driven cellular growth, but its smooth counterpart promotes a larger differentiation extent, outperforming TPMS, as it is aided by larger pore throats lined with microporosity at the scale of osteoblastic geometric features. Abstract : Triply periodic minimal surface and trabecular‐like structures are common approaches in tissue engineering. There are few comparative studies assessing the impact of topology on biological and mechanical performance independent of porosity and surface area. Herein, these two features are controlled, despite design‐to‐manufacture disparities intrinsic to selective laser melting. Smoothed trabecular scaffolds, with more accessible throats lined with microporosity, enhance osteoblastogenesis.