In Vivo Evaluation of 3D-Printed Silica-Based Bioactive Glass Scaffolds for Bone Regeneration

Abstract

Bioactive glasses are often designed as porous implantable templates in which newly-formed bone can grow in three dimensions (3D). This research work aims to investigate the bone regenerative capability of silicate bioactive glass scaffolds produced by robocasting in comparison with powder and granule-like materials (oxide system: 47.5SiO2-10Na2O-10K2O-10MgO-20CaO-2.5P2O5, mol.%). Morphological and compositional analyses performed by scanning electron microscopy (SEM), combined with energy dispersive spectroscopy (EDS) after the bioactivity studies in a simulated body fluid (SBF) confirmed the apatite-forming ability of the scaffolds, which is key to allowing bone-bonding in vivo. The scaffolds exhibited a clear osteogenic effect upon implantation in rabbit femur and underwent gradual resorption followed by ossification. Full resorption in favor of new bone growth was achieved within 6 months. Osseous defect healing was accompanied by the formation of mature bone with abundant osteocytes and bone marrow cells. These in vivo results support the scaffold’s suitability for application in bone tissue engineering and show promise for potential translation to clinical assessment.

Bioactive Glass-Ceramic Scaffolds Coated with Hyaluronic Acid–Fatty Acid Conjugates: A Feasibility Study

“…Cracking ( Figure 8 a,c) was the result of vacuum dehydration during sputter-coating prior to SEM analysis. After 7 days of immersion in SBF, EDS analysis revealed a Ca-to-P ratio of about 1.5 (atomic ratio), which is typical of the Ca-deficient hydroxyapatite formed on the surface of bioactive silicate glasses of various compositions [ 30 , 31 , 32 , 33 ]. A comparable Ca-to-P ratio was also found on the surface of robocast 47.5B scaffolds also soaked in SBF for 7 days.…”

Zinc and Strontium-Substituted Bioactive Glass Nanoparticle/Alginate Composites Scaffold for Bone Regeneration

“…An apatite-rich layer (cauliflower-like apatite) on the surface of the scaffolds formed more substantially on the surface of the Zn-Sr-BGNP: Alg composite scaffolds after soaking in the SBF solution for 21 days than on the alginate scaffolds. The formation of this apatite layer helped recruit cells to the scaffold and assisted with the cell attachment [ 28 , 36 ]. EDX analysis was conducted to determine the chemical composition of the mineral seen in the SEM images.…”

3D-Printing for Critical Sized Bone Defects: Current Concepts and Future Directions

“…BG can be used as a raw material for a variety of 3D printing techniques, including SLS, SLA, and FDM [ 171 ]. Tulyaganov et al demonstrated the effectiveness of 3D-printed silica-based BG in forming hydroxyapatite within simulated body fluid (SBF), as well as an in vivo 4.5 mm rabbit femoral defect model, in which the 3D-printed BG scaffolds resulted in osseous defect healing and the formation of new bone [ 172 ].…”