3D Printing of Bone‐Mimetic Scaffold Composed of Gelatin/β‐Tri‐Calcium Phosphate for Bone Tissue Engineering

Abstract

biodegradable polymer scaffolds were widely studied for bone regeneration because the metal implants have the limitations of non-degradability and high rigidity. [2,3] Common methods for fabricating such a scaffold include particulate leaching, electrospinning, and freeze-drying. However, these methods have limited reproducibility and versatility in their manufacturing processes. [4] To solve these problems, the 3D bioprinting technology for making scaffolds by stacking printing materials has been applied. [5] This 3D bioprinting technology can control the architecture of fabricated structures, so that it only comprises interconnected networks, and also controls the shape of the scaffold. Interconnected pores are an important component of tissue engineering scaffolds because they play roles in cell viability, migration, proliferation, and differentiation. [6] In addition, reproducibility can be guaranteed by bioprinting. β-tri-calcium phosphate (β-TCP) is known to form new bone with osteoconductive properties and are widely applied for bone regeneration. The solubility of β-TCP is higher than that of hydroxyapatite, so it forms higher-density aggregates to bone defects, thereby promoting bone formation. [7,8] Gelatin, a natural polymer derived from partially hydrolyzed collagen, has biological properties such as biocompatibility and 3D printed scaffolds composed of gelatin and β-tri-calcium phosphate (β-TCP) as a biomimetic bone material are fabricated, thereby providing an environment appropriate for bone regeneration. The Ca 2+ in β-TCP and COO − in gelatin form a stable electrostatic interaction, and the composite scaffold shows suitable rheological properties for bioprinting. The gelatin/β-TCP scaffold is crosslinked with glutaraldehyde vapor and unreacted aldehyde groups which can cause toxicity to cells is removed by a glycine washing. The stable binding of the hydrogel is revealed as a result of FTIR and degradation rate. It is confirmed that the composite scaffold has compressive strength similar to that of cancellous bone and 60 wt% β-TCP groups containing 40 wt% gelatin have good cellular activity with preosteoblasts. Also, in the animal experiments, the gelatin/β-TCP scaffold confirms to induce bone formation without any inflammatory responses. This study suggests that these fabricated scaffolds can serve as a potential bone substitute for bone regeneration.

3D-Printed Ginsenoside Rb1-Loaded Mesoporous Calcium Silicate/Calcium Sulfate Scaffolds for Inflammation Inhibition and Bone Regeneration

“…We further examined the GR scaffold via H&E, Masson’s trichrome (MT), and von Kossa staining (VK) and found it could promote bone regeneration and bone formation effectively in vivo [ 48 ]. Consistent with the in vitro results, H&E staining indicated that the hard tissue morphology presented more tibia integrity in the G5 scaffold groups than the G0 scaffold [ 49 ]. MT and VK staining also showed that collagen and calcification were increased in the G5 scaffold after 4 and 8 weeks of implantation.…”

Bone Regeneration by Dedifferentiated Fat Cells Using Composite Sponge of Alfa-Tricalcium Phosphate and Gelatin in a Rat Calvarial Defect Model

“…Moreover, the FTIR analysis did not reveal any significant change between α-TCP alone and the composite. The peak for GS (1631 cm −1 ) slightly shifted to a higher wave number (1640 cm −1 ) in the α-TCP/GS, due to the electrostatic interaction between calcium ions in α-TCP and carboxyl groups in gelatin [25,26].…”

Bioengineered Living Bone Grafts—A Concise Review on Bioreactors and Production Techniques In Vitro

“…Moreover, they demonstrated, using a rat model, that fabricated novel 3D printed biomaterial enhanced bone formation. In another study, Jeong et al [62] showed that 3D printed bone scaffolds containing gelatin and β-TCP were supportive to preosteoblasts' (MC3T3-E1 cells) adhesion, proliferation, and differentiation in vitro. Moreover, the scaffold stimulated bone formation in the animal experiments (a rat model).…”