A dentin-derived hydrogel bioink for 3D bioprinting of cell laden scaffolds for regenerative dentistry

Abstract

Recent studies in tissue engineering have adopted extracellular matrix (ECM) derived scaffolds as natural and cytocompatible microenvironments for tissue regeneration. The dentin matrix, specifically, has been shown to be associated with a host of soluble and insoluble signaling molecules that can promote odontogenesis. Here, we have developed a novel bioink, blending printable alginate (3% w/v) hydrogels with the soluble and insoluble fractions of the dentin matrix. We have optimized the printing parameters and the concentrations of the individual components of the bioink for print accuracy, cell viability and odontogenic potential. We find that, while viscosity, and hence printability of the bioinks, was greater in the formulations containing higher concentrations of alginate, a higher proportion of insoluble dentin matrix proteins significantly improved cell viability; where a 1:1 ratio of alginate and dentin (1:1 Alg-Dent) was most suitable. We further demonstrate high retention of the soluble dentin molecules within the 1:1 Alg-Dent hydrogel blends, evidencing renewed interactions between these molecules and the dentin matrix post crosslinking. Moreover, at concentrations of 100 μg ml, these soluble dentin molecules significantly enhanced odontogenic differentiation of stem cells from the apical papilla encapsulated in bioprinted hydrogels. In summary, the proposed novel bioinks have demonstrable cytocompatibility and natural odontogenic capacity, which can be a used to reproducibly fabricate scaffolds with complex three-dimensional microarchitectures for regenerative dentistry in the future.

Nucleotide lipid-based hydrogel as a new biomaterial ink for biofabrication

“…3A). It is in accordance with previous studies showing that HGFs and SCAPs were resistant to shear stress and pressure during extrusion printing [48][49][50] . Moreover, SCAPs viability decreased while HGF viability remained high over time (Fig.…”

Three‐dimensional printing biotechnology for the regeneration of the tooth and tooth‐supporting tissues

“…Additionally, DIW systems have been used to fabricate multiple functional tissues, including aortic valves, branched vascular trees, liver, cartilage, neural tissue constructs, and in vitro tumor models (R. Chang, Nam, & Sun, ; Duan, Hockaday, Kang, & Butcher, ; Faulkner et al, ; Hsieh, Lin, & Hsu, ; Markstedt et al, ; Norotte, Marga, Niklason, & Forgacs, ; F. Xu et al, ). In the latest invention of novel bioink for dentistry regeneration, the DIW system was used to test the printability of this bioink encapsulated with odontoblast‐like cells (Athirasala et al, ).…”

“…Ansari et al () encapsulated dental‐derived mesenchymal stem cells (MSCs) in certain elasticity and porosity alginate hydrogels, which showed high cell viability. Athirasala et al () applied alginate to produce a novel dental bioink with favorable printability and cytocompatibility while encapsulated with odontoblast cells.…”

“…Tooth dentin matrix was reported to be a suitable scaffold or an inductive microenvironment for the construction of the tooth root. It is worth mentioning that a soluble dentin matrix, combined with alginate, has been produced as a novel bioink, showing favorable printability, cytocompatibility and natural odontogenic capacity (Athirasala et al, ).…”

“…SCAPs, a type of dental stem cell essential for the development of the dental pulp–dentin complex, alveolar bone, and tooth root (Bakopoulou et al, ; Sonoyama et al, ), have been isolated from the root tips of growing teeth and are similar to DPSCs but with a markedly higher proliferative capacity and a greater capacity for dentin regeneration (Bakopoulou et al, ; B. Yang et al, ). Athirasala et al () extracted SCAPs from apical papilla of human third molars and encapsulated the cells in the dentin‐derived hydrogel. The cell viability was higher than 90% after bioprinting via the DIW system, and the cells were cultured for at least 5 days.…”