3D Electrospun Scaffolds as a Cone for Dental Pulp Regeneration

Objectives: New tissue engineering strategies aim to replace actual endodontic treatments, for diseased or necrotic pulp, by developing biomaterials able to restore the lost tissue and to maintain the ability of the pulp to prevent future injuries. Currently, the most attractive strategy involves cell transplantation. Stem cell isolation and culture are well understood, but the transposition of their use in clinic remains challenging. In this context, we developed an optimized porous cone-shaped scaffold able to recruit and activate the host’s endogenous cells surrounding the root canal apex.
Methods: First, porous membranes were fabricated using an original method combining electrospinning and electrospraying. Membranes were structured by an alternating deposition of nanofibers and particles on a micro-patterned collector. They were made of biocompatible polymers, poly(lactic acid) and poly(ε-caprolactone), and functionalized with tannic acid bringing antimicrobial properties. The control of a sufficient porosity was required to ensure cell migration through the entire membrane; it was carried out by laser drilling that generate holes corresponding to open pore size of 150 to 200 micrometers. Finally, the membranes were rolled as a cone of 15 mm long to perfectly fill the root canal after endodontic preparation.
The in vitro potential of pulp-like regeneration was assessed by studying the capacity of dental pulp stem cells (DPSCs) to proliferate, migrate and differentiate into the plane membranes and the cone-shape scaffolds, placed into micro-bioreactors mimicking the root canal space.
Results: The biocompatibility of the membranes has been demonstrated. They were no cytotoxic and DPSC proliferated and differentiated on the surface. Confocal 3D reconstructions assessed that DPSCs colonize the scaffolds in depth.
Conclusions: Biocompatible 3D porous cone were developed to regenerate dental pulp by cell homing. Good results of cell colonization and differentiation demonstrated the hopeful potential of the membranes to induce pulp-like tissue.