Injectable Xenogeneic Dental Pulp Decellularized Extracellular Matrix Hydrogel Promotes Functional Dental Pulp Regeneration

Abstract

The present challenge in dental pulp tissue engineering scaffold materials lies in the development of tissue-specific scaffolds that are conducive to an optimal regenerative microenvironment and capable of accommodating intricate root canal systems. This study utilized porcine dental pulp to derive the decellularized extracellular matrix (dECM) via appropriate decellularization protocols. The resultant dECM was dissolved in an acid pepsin solution to form dECM hydrogels. The analysis encompassed evaluating the microstructure and rheological properties of dECM hydrogels and evaluated their biological properties, including in vitro cell viability, proliferation, migration, tube formation, odontogenic, and neurogenic differentiation. Gelatin methacrylate (GelMA) hydrogel served as the control. Subsequently, hydrogels were injected into treated dentin matrix tubes and transplanted subcutaneously into nude mice to regenerate dental pulp tissue in vivo. The results showed that dECM hydrogels exhibited exceptional injectability and responsiveness to physiological temperature. It supported the survival, odontogenic, and neurogenic differentiation of dental pulp stem cells in a 3D culture setting. Moreover, it exhibited a superior ability to promote cell migration and angiogenesis compared to GelMA hydrogel in vitro. Additionally, the dECM hydrogel demonstrated the capability to regenerate pulp-like tissue with abundant blood vessels and a fully formed odontoblast-like cell layer in vivo. These findings highlight the potential of porcine dental pulp dECM hydrogel as a specialized scaffold material for dental pulp regeneration.

Influence of extracellular matrix scaffolds on histological outcomes of regenerative endodontics in experimental animal models: a systematic review

“…Different animal models were used in the included studies. The majority used mice [ 38 , 39 , 41 , 42 , 45 , 46 , 48 , 50 , 51 , 53 ] followed by rats [ 43 , 44 , 49 , 52 ], pigs [ 39 , 40 ] and beagle dogs [ 23 , 47 ]. The main source of ECM used was swine [ 23 , 39 , 41 , 47 , 53 ], human [ 46 , 48 , 50 ] or bovine dental pulp [ 43 – 45 ].…”

“…The majority used mice [ 38 , 39 , 41 , 42 , 45 , 46 , 48 , 50 , 51 , 53 ] followed by rats [ 43 , 44 , 49 , 52 ], pigs [ 39 , 40 ] and beagle dogs [ 23 , 47 ]. The main source of ECM used was swine [ 23 , 39 , 41 , 47 , 53 ], human [ 46 , 48 , 50 ] or bovine dental pulp [ 43 – 45 ]. Others used cell-generated ECM [ 38 , 42 ], swine tooth bud [ 40 ], human amniotic membrane [ 49 , 52 ] and rats’ submandibular glands [ 51 ].…”

“…Others used cell-generated ECM [ 38 , 42 ], swine tooth bud [ 40 ], human amniotic membrane [ 49 , 52 ] and rats’ submandibular glands [ 51 ]. Regarding the study model, scaffolds were ectopically transplanted in six studies [ 38 , 39 , 43 , 44 , 46 , 52 ], semi-orthotopically transplanted in twelve studies [ 39 – 42 , 45 , 47 – 53 ] and orthotopically transplanted in just one study [ 23 ]. In terms of the regenerative approach, two thirds of the included studies used cell-seeded scaffolds [ 39 – 42 , 45 , 46 , 48 – 53 ] while the rest used cell-free scaffolds [ 23 , 38 , 43 , 44 , 47 ].…”

“…Regarding the study model, scaffolds were ectopically transplanted in six studies [ 38 , 39 , 43 , 44 , 46 , 52 ], semi-orthotopically transplanted in twelve studies [ 39 – 42 , 45 , 47 – 53 ] and orthotopically transplanted in just one study [ 23 ]. In terms of the regenerative approach, two thirds of the included studies used cell-seeded scaffolds [ 39 – 42 , 45 , 46 , 48 – 53 ] while the rest used cell-free scaffolds [ 23 , 38 , 43 , 44 , 47 ]. Six of the former studies also compared between the two approaches [ 40 , 45 , 48 , 49 , 51 , 52 ].…”

“…Six of the former studies also compared between the two approaches [ 40 , 45 , 48 , 49 , 51 , 52 ]. As for the scaffold form, this was either tissue sheets placed within either treated dentin matrix TDM [ 39 , 42 , 47 , 51 , 53 ] /tooth slices [ 41 , 45 , 48 ], or freeze-dried sponges [ 43 , 49 ] or sheets [ 23 , 44 , 51 ], powder [ 46 ], hydrogel microspheres [ 50 ], injectable hydrogel [ 52 , 53 ] or whole decellularized tooth bud [ 40 ]. Only four studies used crosslinked scaffolds [ 43 , 49 , 50 , 52 ].…”