Copper-Loaded Chitosan-Polyphosphate Scaffold – A Promising Innovation for Regenerative Endodontics
The regeneration of dental pulp and dentin is one of the most exciting research areas in modern dentistry. Especially in immature teeth with necrotic pulp and apical periodontitis, restoring tooth vitality remains a major challenge.
Conventional treatments such as apexification stop disease progression but do not promote further root development. Regenerative endodontic procedures (REPs), on the other hand, aim for true tissue regeneration—but persistent infections and root canal calcification continue to limit clinical success.
A research team at Dalhousie University (Canada) has now developed an innovative scaffold that addresses several of these issues simultaneously: a copper-loaded chitosan-polyphosphate scaffold (Chi-PP-Cu).
A Synergistic Combination: Chitosan, Polyphosphate, and Copper
The newly developed scaffold combines three bioactive components with complementary properties:
- Chitosan, a natural biopolymer derived from chitin, known for its biocompatibility, antimicrobial activity, and support of cell growth.
- Polyphosphate (PP), an inorganic polyanion that promotes cell proliferation and inhibits unwanted mineralization through calcium chelation.
- Copper ions (Cu²⁺), which provide strong antibacterial activity while also stimulating angiogenesis and tissue regeneration.
The combination of these three materials resulted in a porous, three-dimensional scaffold with a high vertical wicking rate (0.5 mm/s), enabling efficient fluid transport and cell migration within the root canal.
Controlled Release and Excellent Biocompatibility
The scaffold was prepared using medium molecular weight chitosan (Glentham Life Sciences, DDA ≥ 90%, 125 kDa). Complexation with polyphosphate produced a stable polyelectrolyte network that significantly slowed down copper ion release. After 24 hours, only about 9% of the incorporated copper was released—a major improvement compared to pure chitosan–copper systems, which tend to release copper rapidly and thus cause cytotoxic effects. The lowest tested concentration (Chi-PP-Cu1) released approximately 10 ppm of copper—enough to inhibit Enterococcus faecalis without affecting cell viability. In vitro, fibroblasts and stem cells of the apical papilla (SCAP) remained viable, while higher copper concentrations (≥ 20 ppm) were cytotoxic.
Cell-Friendly, Antibacterial, and Anti-Calcifying
Biological tests showed that the copper-loaded scaffold inhibited E. faecalis growth by up to 68% over 14 days. At the same time, it supported the odontogenic differentiation of SCAP cells, a key step in regenerating the dentin–pulp complex. Notably, the polyphosphate component of the scaffold significantly prevented calcification in cell cultures without impairing cell differentiation. This is clinically relevant, as excessive mineralization can lead to root canal obliteration and compromise the success of regenerative therapies.
Biodegradable and Clinically Applicable
After 28 days, about half of the scaffold mass had degraded, indicating good biodegradability and suitability for clinical application. Moreover, the conical 3D shape, mimicking natural root anatomy, allows for practical insertion into the root canal while supporting tissue ingrowth.
The research team highlights that this development represents an important step toward antibiotic-free biomaterials for regenerative endodontics.
Conclusion
The copper-loaded chitosan-polyphosphate scaffold combines:
- Biocompatibility and biodegradability
- Controlled antimicrobial activity
- Inhibition of unwanted calcification
- Support for cell viability and differentiation
These features make it a highly promising candidate for dental tissue regeneration, especially for use in children and adolescents whose teeth are still developing. Future studies will determine whether this system also proves effective in vivo and could pave the way for a new generation of copper-based chitosan biomaterials in dentistry.
Quelle
Moussa, H., Mello, I., Leung, B., & Filiaggi, M. (2025). Chitosan-Polyphosphate Scaffold Loaded with Copper for Endodontic Regeneration: A Laboratory Study. Dalhousie University, Halifax, Canada. https://doi.org/10.1101/2025.10.30.685681
First published on 20th of November 2025
Revised on 20th of November 2025