Extrusion-based 3D printed magnesium scaffolds with multifunctional MgF₂ and MgF₂-CaP coatings

Area of Science:

• Biomaterials Science
• Additive Manufacturing
• Orthopedic Engineering

Background:

• Additively manufactured (AM) biodegradable magnesium (Mg) scaffolds offer potential for bone regeneration but face challenges like oxidation and poor corrosion resistance.
• Extrusion-based 3D printing of Mg scaffolds improves structure but requires enhanced bioactivity and controlled biodegradation.
• Current AM Mg scaffolds struggle with safety and severe oxidation, limiting clinical application.

Purpose of the Study:

• To develop and evaluate novel extrusion-based 3D printed porous Mg scaffolds coated with MgF2 and MgF2-CaP.
• To enhance corrosion resistance and biocompatibility of AM Mg scaffolds for bone substitute applications.
• To assess the mechanical properties, biodegradation, and osteoblast response of coated Mg scaffolds.

Main Methods:

• Fabrication of porous Mg scaffolds using extrusion-based 3D printing.
• Coating of scaffolds with MgF2 and MgF2-CaP to improve surface properties.
• Evaluation of mechanical properties, in vitro biodegradation, electrochemical response, and biocompatibility (MC3T3-E1 preosteoblast culture).

Main Results:

• MgF2-CaP coatings significantly improved corrosion resistance, reducing the biodegradation rate to 0.2 mm y-1.
• Coated scaffolds maintained mechanical properties comparable to trabecular bone during in vitro immersion.
• Coated Mg scaffolds demonstrated good biocompatibility with MC3T3-E1 preosteoblasts.

Conclusions:

• MgF2-CaP coated porous Mg scaffolds produced by extrusion-based 3D printing offer enhanced corrosion resistance and biocompatibility.
• These advanced scaffolds show significant potential for clinical use as bone substitutes in bone defect repair.
• The study highlights a promising approach to overcome limitations of current AM Mg scaffolds.