Oxygen Self-Supplied Nanoplatform for Enhanced Photodynamic Therapy against Enterococcus Faecalis within Root Canals

Area of Science:

• Biomaterials Science
• Endodontics
• Photodynamic Therapy

Background:

• Persistent endodontic infections require novel antimicrobial strategies.
• Antibacterial photodynamic therapy (aPDT) shows promise but is limited by root canal hypoxia.
• Developing oxygen-scavenging materials is crucial for enhancing aPDT efficacy.

Purpose of the Study:

• To develop a self-oxygenating nanohybrid drug delivery system for enhanced aPDT in endodontic infection management.
• To investigate the efficacy of Ce6/CaO2/ZIF-8@polyethylenimine (PEI) in eradicating Enterococcus faecalis (E. faecalis) biofilms.
• To address the challenge of hypoxia in root canal environments to improve antimicrobial treatment outcomes.

Main Methods:

• Fabrication of a Ce6/CaO2/ZIF-8@polyethylenimine (PEI) nanohybrid using a bottom-up strategy.
• In vitro evaluation of antibacterial activity against planktonic and biofilm E. faecalis under laser irradiation.
• In situ assessment of biofilm eradication within root canal systems.
• Characterization of oxygen generation and bacterial targeting capabilities.

Main Results:

• The Ce6/CaO2/ZIF-8@PEI nanohybrid successfully generated oxygen, alleviating hypoxia.
• The material demonstrated potent antibacterial effects against E. faecalis biofilms in vitro.
• Effective in situ elimination of mature E. faecalis biofilms within the root canal system was achieved.
• PEI coating facilitated precise targeting of bacteria.

Conclusions:

• The developed nanohybrid drug system effectively overcomes hypoxia-induced limitations in aPDT for endodontic infections.
• This oxygen-self-supplying approach offers a promising strategy for managing persistent root canal infections.
• The findings present a viable alternative for enhancing photosensitizer efficacy in clinical endodontic treatments.