Bilayered scaffold with 3D printed stiff subchondral bony compartment to provide constant mechanical support for long-term cartilage regeneration

Abstract

Background/Objective We seek to figure out the effect of stable and powerful mechanical microenvironment provided by Ti alloy as a part of subchondral bone scaffold on long-term cartilage regeneration. Methods: we developed a bilayered osteochondral scaffold based on the assumption that a stiff subchondral bony compartment would provide stable mechanical support for cartilage regeneration and enhance subchondral bone regeneration. The subchondral bony compartment was prepared from 3D printed Ti alloy, and the cartilage compartment was created from a freeze-dried collagen sponge, which was reinforced by poly-lactic-co-glycolic acid (PLGA). Results In vitro evaluations confirmed the biocompatibility of the scaffold materials, while in vivo evaluations demonstrated that the mechanical support provided by 3D printed Ti alloy layer plays an important role in the long-term regeneration of cartilage by accelerating osteochondral formation and its integration with the adjacent host tissue in osteochondral defect model at rabbit femoral trochlea after 24 weeks. Conclusion Mechanical support provided by 3D printing Ti alloy promotes cartilage regeneration by promoting subchondral bone regeneration and providing mechanical support platform for cartilage synergistically. Translational potential statement The raw materials used in our double-layer osteochondral scaffolds are all FDA approved materials for clinical use. 3D printed titanium alloy scaffolds can promote bone regeneration and provide mechanical support for cartilage regeneration, which is very suitable for clinical scenes of osteochondral defects. In fact, we are conducting clinical trials based on our scaffolds. We believe that in the near future, the scaffold we designed and developed can be formally applied in clinical practice.

Numerical Simulation Study on Relationship between the Fracture Mechanisms and Residual Membrane Stresses of Metallic Material

“…For the last experimental work, a biomaterial was fabricated using the metallic filler polymer reinforced method [ 44 , 45 , 46 ] to provide the requisite mechanical and structural strengths [ 47 ] for the scaffold integrity [ 48 ]. The tensile strength and flexural strength for this biomaterial made of 30% low brass filler and 70% polyester urethane liquid were found to be 203 MPa and 1015 MPa, respectively [ 18 , 49 ].…”

Periosteum and development of the tissue-engineered periosteum for guided bone regeneration

“…Subsequently, drugs, key factors, BMP-2, and vascular endothelial growth factor (VEGF) were attached to the scaffolds or attached to capsules, particles, and other structures to achieve the effect of controlled release, to provide suitable conditions for new bone formation and make the cells more osteogenic [ 71 , 72 ]. However, abnormalities in the physiological levels of bioactive factors can produce serious side effects [ 73 ], such as inflammation and immune responses [ 74 ], excessive osteogenesis, and ectopic osteogenesis [ 75 ].…”

3D gel-printed porous magnesium scaffold coated with dibasic calcium phosphate dihydrate for bone repair in vivo

“…In our previous researches [ [28] , [29] , [30] , [31] ], we developed 3D gel printing (3DGP) and used it to prepare a variety of materials, such as ceramics and metals. In this paper, a Mg scaffold with a controllable pore structure was prepared by the 3DGP method, and its surface was modified with a calcium phosphate coating.…”