Rational Design and Fabrication of Porous Calcium-Magnesium Silicate Constructs That Enhance Angiogenesis and Improve Orbital Implantation

Tissue integration of orbital implants, following orbital enucleation treatment, represents a challenge for rapid fibrovascularization, long-time stability, anti-infection, and even induction of vascule regeneration. The objective of this study was to develop porous calcium magnesium silicate materials, with good stability, bioactivity, and antibacterial potential as new orbital fillers. Three-dimensional (3D) diopside scaffolds (low dissolvability) were fabricated by direct ceramic ink writing assembly and then followed by one-step sintering at 1150 degrees C for 3 h. The pore wall of the scaffold was modified by another calcium-magnesium silicate, such as bredigite or akermanite, which dissolves quickly but shows greater angiogenic potential. These two Ca-Mg-silicates can be coated onto the pore strut, and the coating layers were observed to slowly dissolve in Tris buffer. The vascularization-favorable Cu ions, which had been doped into the bredigite or akermanite coating, could also be measured in the immersion medium. A primary angiogenic test in a panniculus carnosus muscle model in rabbit indicated that the Cu-doped bredigite and akermanite coatings were significantly beneficial for the neovascularization in the early stages. These results suggest that the diopside-based porous materials modified with functional coatings hold great potential for application in orbital reconstruction.