Evaluation of Injectable Hyaluronic Acid-Based Hydrogels for Endodontic Tissue Regeneration

Abstract

Dental pulp tissue engineering (TE) endeavors to regenerate dentin/pulp complex by combining a suitable supporting matrix, stem cells, and biochemical stimuli. Such procedures foresee a matrix that can be easily introduced into the root canal system (RCS) and tightly adhere to dentin walls to assure the dentin surface’s proper colonization with progenitor cells capable of restoring the dentin/pulp complex. Herein was investigated an injectable self-setting hyaluronic acid-based (HA) hydrogel system, formed by aldehyde-modified (a-HA) with hydrazide-modified (ADH), enriched with platelet lysate (PL), for endodontic regeneration. The hydrogels’ working (wT) and setting (sT) times, the adhesion to the dentine walls, the hydrogel’s microstructure, and the delivery of human dental pulp cells (DPCs) were studied in vitro. Hydrogels incorporating PL showed a suitable wT and sT and a porous microstructure. The tensile tests showed that the breaking point occurs after 4.3106 ± 1.8677 mm deformation, while in the indentation test after 1.4056 ± 0.3065 mm deformation. Both breaking points occur in the hydrogel extension. The HA/PL hydrogels exhibited supportive properties and promoted cell migration toward dentin surfaces in vitro. Overall, these results support using PL-laden HA injectable hydrogels (HA/PL) as a biomaterial for DPCs encapsulation, thereby displaying great clinical potential towards endodontic regenerative therapies.

Self-Crosslinkable Oxidized Alginate-Carboxymethyl Chitosan Hydrogels as an Injectable Cell Carrier for In Vitro Dental Enamel Regeneration

“…We then prepared the hydrogels by mixing the aqueous solutions of oxidized alginate and carboxymethyl chitosan followed by incubation at 37 °C. The kinetics of crosslinking through the Schiff base reaction were previously found by other studies to be contingent upon the pH, temperature, and the type and content of amine and aldehyde groups in the polymers [ 41 , 70 ].…”

A Comprehensive Review of Cross-Linked Gels as Vehicles for Drug Delivery to Treat Central Nervous System Disorders

“…Schiff base cross-linking reactions are reactions between molecules containing amine, alcohol, or hydrazide moieties and an aldehyde molecule [ 87 ]. The reactions involve a dynamic covalent amine bond formation via the cross-linking of amine groups and aldehyde groups and depend on the pH, temperature, and type of aldehydes/amines involved in the reaction [ 182 , 183 ]. Enzymes form covalent bonds between polymers, they are significantly sensitive and specific in chemical reactions [ 80 ].…”

“… Schematic of drug release from nanogels in response to various stimuli [Obtained and reproduced without any changes from [ 183 ] and Gels MDPI in accordance with Creative Commons Attribution License (CC BY 4.0)]. …”

HYDRHA: Hydrogels of hyaluronic acid. New biomedical approaches in cancer, neurodegenerative diseases, and tissue engineering

“…Among the natural polymers selected for the realization of 3D cellular systems, for dermatological formulations [ 26 ] and regenerative medicine [ [27] , [28] , [29] , [30] ] the most popular biomaterial used is hyaluronic acid (HA) [ 31 ]. HA is a molecule easy to customize chemically and mechanically, with high-water retention and viscoelastic properties [ 32 ] and an indispensable component of the ECM [ 33 , 34 ].…”