Recent Progress in 3D Printing of Elastic and High-Strength Hydrogels for the Treatment of Osteochondral and Cartilage Diseases

Abstract

Despite considerable progress for the regenerative medicine, repair of full-thickness articular cartilage defects and osteochondral interface remains challenging. This low efficiency is largely due to the difficulties in recapitulating the stratified zonal architecture of articular cartilage and engineering complex gradients for bone-soft tissue interface. This has led to increased interest in three-dimensional (3D) printing technologies in the field of musculoskeletal tissue engineering. Printable and biocompatible hydrogels are attractive materials for 3D printing applications because they not only own high tunability and complexity, but also offer favorable biomimetic environments for live cells, such as porous structure, high water content, and bioactive molecule incorporation. However, conventional hydrogels are usually mechanically weak and brittle, which cannot reach the mechanical requirements for repair of articular cartilage defects and osteochondral interface. Therefore, the development of elastic and high-strength hydrogels for 3D printing in the repairment of cartilage defects and osteochondral interface is crucial. In this review, we summarized the recent progress in elastic and high-strength hydrogels for 3D printing and categorized them into six groups, namely ion bonds interactions, nanocomposites integrated in hydrogels, supramolecular guest–host interactions, hydrogen bonds interactions, dynamic covalent bonds interactions, and hydrophobic interactions. These 3D printed elastic and high-strength hydrogels may provide new insights for the treatment of osteochondral and cartilage diseases.

Unraveling of Advances in 3D-Printed Polymer-Based Bone Scaffolds

“…Printable and biocompatible polymer materials are the optimum material in the applications of 3D printing. Because they possess high adjustability and complexity and provide a prefer bionic environment for living cells [ 63 ]. Therefore, more and more people have begun to commit to the research of biological materials needed for 3D printing in recent years, especially in polymer-based composite print materials.…”

3D Printing for Bone-Cartilage Interface Regeneration

“…Bioink is the base material for scaffold formation and are generally flowable liquids that can be easily squeezed and rapidly solidified, retaining their shape by physical or chemical stimulation ( Dai et al, 2020 ). The porous structure, adjustable mechanical properties, and high water content can provide an appropriate environment for different cells to mimic the ECM.…”

Therapeutic application of hydrogels for bone-related diseases

“…Current treatment strategies mainly include repair of microfractures, and autologous chondrocyte implantation, osteochondral autografts and allografts ( Benazzo et al, 2008 ; Selmi et al, 2008 ; Hamblin et al, 2010 ; Haene et al, 2012 ; MacDonald et al, 2016 ; Polat et al, 2016 ; Gou et al, 2020 ). Despite their widespread usage, these approaches have significant drawbacks and limitations ( Dai et al, 2020 ). At present, therapeutic techniques targeting cartilage lesions are difficult to cure cartilage damage, thereby accelerating the development of alternative tissue engineering strategies.…”