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

Wenli Dai,Xiaoqing Hu,Muyang Sun,Xi Leng,Yingfang Ao

doi:10.3389/fbioe.2020.604814

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.

Highlights

Damage of cartilage and osteochondral tissue is one of the most common health problems worldwide, which occurred due to various reasons such as disease, injuries, and trauma
It is promising to construct high-strength, elastic, and biomimetic hydrogels to mimic the mechanical properties of native articular cartilage osteochondral tissues
The hydrogels can significantly change over time without permanent changes to the hydrogel network (Sun et al, 2012). Due to these attractive properties, recently, non-covalently formed hydrogels have emerged as a neoteric class of scaffolds that integrate hydrogels with reversible crosslinking to develop advanced features including high-strength, elastic, and selfhealing properties, which provide great advantages for cartilage and osteochondral tissue engineering

Summary

Introduction

Damage of cartilage and osteochondral tissue is one of the most common health problems worldwide, which occurred due to various reasons such as disease, injuries, and trauma. It is promising to construct high-strength, elastic, and biomimetic hydrogels to mimic the mechanical properties of native articular cartilage osteochondral tissues. Due to these attractive properties, recently, non-covalently formed hydrogels have emerged as a neoteric class of scaffolds that integrate hydrogels with reversible crosslinking to develop advanced features including high-strength, elastic, and selfhealing properties, which provide great advantages for cartilage and osteochondral tissue engineering.

Results

Conclusion