Moisture based three-dimensional printing of calcium phosphate structures for scaffold engineering

Area of Science:

• Materials Science
• Biomedical Engineering
• Additive Manufacturing

Background:

• Powder-based three-dimensional printing (3DP) offers versatility for tissue engineering scaffolds but faces limitations in resolution and accuracy.
• Optimizing powder properties for specific layer thicknesses is crucial for improving 3DP scaffold quality.

Purpose of the Study:

• To investigate the impact of moisture application, layer thickness, and batch size on the surface roughness and geometrical accuracy of 3DP scaffolds.
• To explore the potential of moisture-based 3DP for enhancing scaffold resolution and accuracy.

Main Methods:

• Systematic quantification of surface roughness and geometrical accuracy in 3DP specimens.
• Variation analysis based on moisture application time (0-20s), layer thickness (44 and 88 μm), and specimens per batch (6 and 12).
• Utilized a custom moisture application device integrated with the print head.

Main Results:

• Achieved a best surface roughness of 25 μm with 5s moisture application and 44 μm layer thickness.
• Higher geometrical accuracy was observed with 88 μm layers due to improved powder bed stability.
• Moisture application enabled 44 μm layer 3DP and enhanced accuracy even for powders optimized for thicker layers.
• Recycled humidified powder showed beneficial effects on reactivity.

Conclusions:

• Moisture-based 3DP is a promising approach for achieving high-resolution scaffolds.
• This method addresses key limitations in resolution and accuracy for scaffold engineering.
• Optimizing moisture application and layer thickness can significantly enhance 3DP scaffold quality.