Digital Light Processing 3D Printing of Gyroid Scaffold with Isosorbide-Based Photopolymer for Bone Tissue...

Bone tissue is frequently transplanted due to its structural diversity across anatomical regions. Current bone substitutes often lack the structural and mechanical similarity to native bone. Extrusion-based 3D printing is widely used, but it has limitations in resolution and mechanical performance. Digital light processing (DLP) offers faster and more precise printing. However, developing biocompatible resins for DLP remains a challenge. Prior research has shown that extrusion methods struggle with high-resolution scaffolds. No prior work had resolved the issue of biocompatible DLP resins for bone scaffolding. This gap motivated the development of new photopolymers. The need for high-resolution, biocompatible scaffolds remains unmet.

This study aimed to develop a biocompatible photopolymer suitable for DLP printing of bone scaffolds. The goal was to create scaffolds with high resolution and mechanical properties similar to cancellous bone. The specific problem was the lack of suitable resins for DLP in bone tissue engineering. The motivation was to advance DLP as a reliable method for fabricating complex scaffolds. The approach involved designing a renewable monomer-based resin. The study also sought to evaluate the osteogenic potential of the scaffolds. The focus was on combining high-resolution printing with biocompatibility. The outcome would support the use of DLP in bone regeneration.

The researchers developed CSMA-2, a photopolymer based on isosorbide, a renewable sugar derivative. The material was tested for its rheological properties suitable for DLP printing. Gyroid scaffolds were printed using DLP to achieve high resolution. The scaffolds were analyzed for compressive modulus to match cancellous bone. Human adipose-derived stem cells were seeded onto the scaffolds. Cell viability was assessed over 21 days of incubation. The expression of osteogenic markers was measured using gene analysis. Calcium deposition from the cells was also evaluated to assess osteogenic activity.

CSMA-2 demonstrated suitable rheological properties for DLP printing. The printed gyroid scaffolds had high resolution and structural accuracy. The compressive modulus of the scaffolds was within the range of human cancellous bone. Human adipose-derived stem cells remained viable for up to 21 days. The cells deposited calcium on the scaffold surfaces. The stem cells expressed osteogenic markers RUNX2, OCN, and OPN. These markers indicated osteogenic differentiation of the cells. The results suggest that the scaffolds supported bone-like tissue formation.

The study showed that CSMA-2 is a viable photopolymer for DLP printing of bone scaffolds. The scaffolds had high resolution and mechanical properties suitable for bone regeneration. The material supported stem cell viability and osteogenic differentiation. The results suggest that CSMA-2 is a promising material for DLP-based tissue engineering. The scaffolds could be used to fabricate complex biomimetic structures. The findings support the use of DLP for high-resolution bone scaffolding. The material's biocompatibility and mechanical properties were confirmed. The authors propose that CSMA-2 could advance DLP applications in bone tissue engineering.