Advances on gradient scaffolds for osteochondral tissue engineering

Abstract

The osteochondral (OC) tissue is one of the most hierarchical and complex structures known and it is composed by two main compartments of hyaline articular cartilage and subchondral bone. It exhibits unique cellular and molecular transitions from the cartilage to the bone layers. OC diseases such as osteoarthritis and traumatic lesions may affect the articular cartilage, calcified cartilage (interface region) and subchondral bone, thus posing great regenerative challenges. Tissue engineering (TE) principles can offer novel technologies and combinatorial approaches that can better recapitulate the biological OC challenges and complexity in terms of biochemical, mechanical, structural and metabolic gradients, and ultimately can provide biofunctional 3D scaffolds with high reproducibility, versatility and adaptability to each patient’s needs, as it occurs in OC tissue defects. The recent reports and future directions dealing with gradient scaffolds for OCTE strategies are overviewed herein. A special focus on clinical translation/regulatory approval is given.

Crystal Growth of 3D Poly(ε‐caprolactone) Based Bone Scaffolds and Its Effects on the Physical Properties and Cellular Interactions

“…[ 36 ] Moreover, several studies also found that stress relaxation is correlated to osteogenesis, with faster stress relaxation significantly improving mesenchymal stem cell (MSC) osteogenic differentiation. [ 24 , 25 , 37 , 38 , 39 ]…”

“…[36] Moreover, several studies also found that stress relaxation is correlated to osteogenesis, with faster stress relaxation significantly improving mesenchymal stem cell (MSC) osteogenic differentiation. [24,25,[37][38][39] Surface elastic modulus and hardness were determined using nanoindentation (Figure 2f,g). Overall, the melt-printed scaffolds have a higher surface hardness and reduced elastic modulus than solvent-printed scaffolds.…”

Advancements in gradient bone scaffolds: enhancing bone regeneration in the treatment of various bone disorders

“…Natural joints are composed of cartilage and subchondral bone, which are connected by a dense calcified cartilage layer [52,53]. In the repair of bone joints, it is important to design a scaffold with a continuous gradient in terms of material composition, structure, mechanical properties, and biological performance [54]. Current joint injuries typically involve damage to both cartilage and subchondral bone [55,56].…”

Research progress on repair of osteochondral defects

“…Osteochondral tissue (OCT) is a composite tissue structure, mainly found in the joints of the body, formed by bone and cartilage tissues arranged in a certain pattern [4]. The most important structures are the articular cartilage (AC), the calcified cartilage zone (CCZ) and the subchondral bone (SSB) and In OCT, the AC accounts for 90%, while the SSB accounts for an almost equal proportion to the CCZ at 5% respectively [5].…”