In vivo XCT bone characterization of lattice structured implants fabricated by additive manufacturing

Abstract

Several cylindrical specimens and dental implants, presenting diagonal lattice structures with different cell sizes (600, 900 and 1200 μm) were additively manufactured by selective laser melting process. Then they were implanted for two months in a sheep. After removal, they were studied by Archimedes’ method as well as X-ray computed tomography in order to assess the penetration of bone into the lattice. We observed that the additive manufactured parts were geometrically conformed to the theoretical specifications. However, several particles were left adhering to the surface of the lattice, thereby partly or entirely obstructing the cells. Nevertheless, bone penetration was clearly visible. We conclude that the 900 μm lattice cell size is more favourable to bone penetration than the 1200 μm lattice cell size, as the bone penetration is 84% for 900 μm against 54% for 1200 μm cell structures. The lower bone penetration value for the 1200 μm lattice cell could possibly be attributed to the short residence time in the sheep. Our results lead to the conclusion that lattice implants additively manufactured by selective laser melting enable better bone integration.

Reconsidering Osteoconduction in the Era of Additive Manufacturing

“…Here, a unit cell of 0.9 mm showed the best bone ingrowth. 88 Pores 3.2 mm in diameter were used for honeycomb-shaped meshes to generate mechanobiologically optimized configurations for scaffolds to successfully treat large bone defects. 89,90 Such mesh-type scaffolds have not been tested or optimized for osteoconduction, but only examined in view of their mechanics and stress shielding capabilities.…”

Hydrostatic High-Pressure Post-Processing of Specimens Fabricated by DLP, SLA, and FDM: An Alternative for the Sterilization of Polymer-Based Biomedical Devices

“…Béduer et al [27] proposed an AM technology that is viable for 3D printing scaffolds used in tissue engineering and considered an autoclave sterilization method after printing, but the effects of the sterilization were not quantified. Obaton et al [28] also considered autoclave sterilization after printing an SLM-processed part, but the effects were not measured.…”

Investigation of new volumetric non-destructive techniques to characterise additive manufacturing parts

“…New non-destructive techniques (NDT) [1] as well as volumetric techniques have to be investigated. X-ray tomography is presently the most appropriate technique [2][3][4] considering that it is a non-contact technique providing a high spatial resolution. However, it is a costly and time-consuming technique which may be unsuitable for mass production.…”