3D-printed biodegradable metallic Mg scaffolds, FHNW School of Life Sciences

Due to its flexibility, selective laser melting (SLM) is used to manufacture permanent, patient-specific, metallic implants made of commercially pure titanium. However, only a few studies on 3D printing magnesium using SLM have been published. We have developed new patient-specific solutions that surgeons could implement toward biodegradable magnesium implants.

Background

The surgical application of permanent implants, e.g. osteosynthesis plates to stabilize fractured bones during healing, may be accompanied by disadvantages in the long-term, in particular in children or adolescent where impaired growth can result.

Furthermore, implant dislocations, implant-associated infections or injuries of nerves and vessels can appear as side effects. Secondary surgeries to remove the implant after successful bone healing and to clinically eradicate this artificial foreign body often are expensive and complex.

Toward strong, biodegradable magnesium implants

Resorbable implants, however, degenerate in-vivo. The foreign material is absorbed and no secondary surgery is necessary. Still, the mechanical strength of existing bioresorbable ceramic or polymeric biomaterials is too low for load-bearing applications. On the contrary, magnesium could be used as a biomaterial for the production of metallic, resorbable implants with sufficient mechanical properties.

• Safety recipient for controlled selective laser melting of magnesium
• Degradable Mg scaffolds produced by selective laser melting
• Preliminary microstructural investigation of Mg cubes produced by SLM
• Customizing the microstructure in three-dimensional Mg structures (see image below)
  

• R. Marek, F. Wohlfender, B. Wiese, M. de Wild, Customizing the microstructure in three-dimensional Mg structures, proceeding of the 9^th Biometal Symposium on Biodegradable Metals for Biomedical Applications, Met-4, 27. European Cells and Materials Meeting Abstracts 2017, Collection 4; Biometal 11 (2017).
• F. Wohlfender, N. Vogt, J. Rüegg, R. Marek, M. de Wild, Effect of process parameters on hardness of SLM-Mg material, Biomed Tech 2016 61, s30 (2016).
• J. Rüegg, S. Böhringer, A. Kessler, R. Schumacher, E. Schkommodau, M. de Wild, Degradable Mg scaffolds produced by selective laser melting, Front. Bioeng. Biotechnol. Conference Abstract: 10^th World Biomaterials Congress
• F. Wohlfender, S. Saxer, B. Wiese, J. Rüegg, A. Dietschy, R. Schumacher, M. de Wild, Preliminary microstructural investigation of Mg produced by SLM, European Cells and Materials 32. Suppl. 1, 24 (2016).
• S. Böhringer, A. Kessler, J. Rüegg, R. Schumacher, E. Schkommodau, M. de Wild, Safety recipient for controlled selective laser melting of magnesium, European Cells and Materials, 30; Suppl. 3, 4 (2015).