Novel hydrogel systems for dentin regeneration

Toronto, ON, Canada – Dental caries, or tooth decay, continues to be the most prevalent infectious disease in the world,presenting significant public health challenges and socio-economic consequences. It leads to the loss of the hard tissues ofthe tooth, followed by inflammation and necrosis of the subjacent dental pulp. In the U.S. alone, over 20 million dental restorationsare placed each year, with failure rates of up to 60%. Hence, there exists a critical need for better biologic therapeuticsto restore the damaged dentin-pulp complex to its original form and function. However, progress in this area has been slowcompared with that in other fields of regenerative medicine.

Tissue-engineering strategies directed at mimicking the natural extracellular matrix have utilized synthetic and non-syntheticscaffolds to direct cell differentiation and matrix mineralization (in the case of bone). The most promising among thenew generation of delivery systems are synthetic peptide hydrogels, which provide a nanostructured matrix highly similar tonatural matrix. Short peptides can be designed to self-assemble into nanofibers, form macroscopic gels, and entrap living cells.With single amino acids as building blocks, the resulting materials are non-toxic, non-inflammatory, and biodegradable. Themodular concept allows for high control over the system and, at the same time, makes it extremely versatile.

Speaking today during the 86th General Session of the International Association for Dental Research, a team of investigatorsfrom Baylor College of Dentistry (Dallas), the University of Regensburg (Germany), and Rice University (Houston)presents its preliminary data describing the results of studies on hydrogels made of peptide amphiphiles, where a short peptidesequence is attached to a fatty acid, which provides the driving force for self-assembly. However, they recently applied adifferent design concept, where the self-assembly of peptide chains is achieved without attaching a hydrophobic tail. Based ontheir design, the chains can include bioactive peptide sequences for cell adhesion, binding of growth factors, or other biologicalmolecules with therapeutic potential. Hence, multidomain peptide hydrogels represent a novel and highly versatilematerial offering a higher degree of control over nanofiber architecture and better chemical functionality.

The overarching goal of this research is to utilize these multidomain peptides as a biomimetic scaffold, along with dentalstem cell therapy, to provide a natural 3D environment that can control and direct the differentiation and function of dentalstem cells for the targeted regeneration of the dentin-pulp complex.

This work is highly translational and innovative, since it capitalizes on a new and previously untested material with novelproperties for the regeneration of the dentin-pulp complex. Importantly, the results will provide the foundation for developingmultidomain peptide scaffolds as novel therapeutics for the regeneration of the dentin-pulp complex.

Source: International & American Association for Dental Research