3D Printing of Calcium Phosphate/Calcium Sulfate with Alginate/Cellulose-Based Scaffolds for Bone Regeneration: Multilayer Fabrication and Characterization

Abstract

Congenital abnormalities, trauma, and disease result in significant demands for bone replacement in the craniofacial region and across the body. Tetra-compositions of organic and inorganic scaffolds could provide advantages for bone regeneration. This research aimed to fabricate and characterize amorphous calcium phosphate (ACP)/calcium sulfate hemihydrate (CSH) with alginate/cellulose composite scaffolds using 3D printing. Alginate/cellulose gels were incorporated with 0%, 13%, 15%, 18%, 20%, and 23% ACP/CSH using the one-pot process to improve morphological, physiochemical, mechanical, and biological properties. SEM displayed multi-staggered filament layers with mean pore sizes from 298 to 377 μm. A profilometer revealed mean surface roughness values from 43 to 62 nm that were not statistically different. A universal test machine displayed the highest compressive strength and modulus with a statistical significance in the 20% CP/CS group. FTIR spectroscopy showed peaks in carbonate, phosphate, and sulfate groups that increased as more ACP/CSH was added. Zero percent of ACP/CSH showed the highest swelling and lowest remaining weight after degradation. The 23% ACP/CSH groups cracked after 60 days. In vitro biocompatibility testing used the mouse osteoblast-like cell line MC3T3-E1. The 18% and 20% ACP/CSH groups showed the highest cell proliferation on days five and seven. The 20% ACP/CSH was most suitable for bone cell regeneration.

Osteoblast-like Cell Differentiation on 3D-Printed Scaffolds Using Various Concentrations of Tetra-Polymers

“…In this study, the 18% ACP/CSH showed the highest ALP and OCN, but the mineralization in the 20% ACP/CSH group was noticeably higher than the 18% ACP/CSH group on day 14 because sulfate ions were rapidly released on day 1 and accumulated more in ECM until day 7, which may subsequently interact with bodily fluids and affect bone mineralization [ 34 ]. However, the mechanical properties of 23%ACP/CSH were less than 20%ACP/CSH, indicating that the scaffold with lower mechanical properties provides less cell differentiation [ 22 ].…”

“…A 0%ACP/CSH group served as the control. To achieve a homogeneous and desirable particle size, the printing ink dispersion was filtered through a 110 μm filter [ 22 ].…”

“…The scaffold was immediately immersed in crosslink for 60 min to complete the set, and then cleaned 5 times with distilled water before freeze-drying for 3 h. Each scaffold was divided into 7 × 7 × 2 mm sections and disinfected using ethylene oxide gas before seeding the cells. All groups were divided into three samples each ( Figure 1 c–e) [ 22 ].…”

Fabricating biodegradable calcium phosphate/calcium sulfate cement reinforced with cellulose:in vitroandin vivostudies

“…24 Recent evidence suggests that CSC/CPC-based composite cement has favorable cytocompatibility for osteoblasts. 25–28 Further, CSC/CPC cement demonstrate the ability to induce bone regeneration in vivo . 29,30…”

“…24 Recent evidence suggests that CSC/CPCbased composite cement has favorable cytocompatibility for osteoblasts. [25][26][27][28] Further, CSC/CPC cement demonstrate the ability to induce bone regeneration in vivo. 29,30 Presently, the most common strategy to overcome the inherent limitations of inorganic cement involves the incorporation of polymer additives into the cement.…”