Tissue engineering at the dentin-pulp interface using human treated dentin scaffolds conditioned with DMP1 or BMP2...

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Dental Research

Background:

• Conventional dental caries management relies on inert biomaterials, failing to regenerate natural tooth structure.
• Existing tissue engineering approaches often produce reparative dentin but do not replicate the tubular microstructure of ortho-dentin.
• The sensory and defensive functions of odontoblasts are compromised in current regenerative strategies.

Purpose of the Study:

• To characterize human EDTA-treated, freeze-dried dentin (HTFD) scaffolds combined with plasmid-carrying nanoparticles (NPs) for dentin regeneration.
• To evaluate the in vitro and in vivo efficacy of HTFD/NPs constructs in promoting ortho-dentin formation and preserving pulp vitality.
• To assess the potential of HTFD/NPs as a tool for personalized reconstruction of the dentin-pulp interface.

Main Methods:

• Synthesized calcium phosphate NPs carrying plasmids encoding dentinogenesis factors (pBMP2/NPs or pDMP1/NPs).
• Conditioned HTFD scaffolds with synthesized NPs and evaluated NP uptake, transfection efficiency, and cell viability using microscopy and flow cytometry.
• Assessed in vitro gene expression and cell phenotype of dental pulp stem cells (DPSCs) on HTFD/NPs constructs via real-time PCR and SEM.
• Evaluated in vivo biocompatibility and regenerative potential after implantation in C57BL6 mice.

Main Results:

• NP uptake and transfection efficiency on DPSCs increased with concentration and time, with an optimal concentration balancing transfectability and viability.
• HTFD/NPs constructs at optimal concentrations preserved DPSC viability in vitro and showed no adverse reactions in vivo.
• Constructs induced significant odontogenic differentiation of DPSCs, confirmed by gene expression (RunX2, ALP, BGLAP, BMP-2, DMP-1, DSPP) and SEM visualization of cellular structures within dentinal tubules.
• Successful recapitulation of ortho-dentin microstructure and odontoblastic layer was observed.

Conclusions:

• HTFD/NPs constructs represent a promising biomaterial for regenerating natural ortho-dentin.
• This approach facilitates the reconstruction of the dentin-pulp interface, preserving pulp vitality.
• The technology holds potential for customized bio-fillings in personalized dental reconstruction.