Ebselen-loaded silver-containing mesoporous bioactive glass for the control of Enterococcus faecalis and Streptococcus mutans in endodontic infections.

OBJECTIVE

Calcium silicate-based sealers are widely used in endodontics, however, their efficacy against persistent biofilms remains limited. This study aimed to investigate the antibacterial and antibiofilm properties, hydroxyapatite (HA)-formation ability, and cytocompatibility of mesoporous bioactive glass loaded with silver and Ebselen (Ebselen/MBG-Ag), a bioceramic material with potential application in future endodontic sealers.

METHODS

Silver-containing mesoporous bioactive glass (MBG-Ag) was synthesized via a sol-gel method, followed by Ebselen loading through solvent impregnation to produce Ebselen/MBG-Ag. The synthesized materials were characterized using Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS) elemental mapping. The release profiles of silver ions and Ebselen were evaluated using inductively coupled plasma mass spectrometry (ICP-MS) and high-performance liquid chromatography (HPLC), respectively. Antibacterial and antibiofilm activities against Enterococcus faecalis (E. faecalis) and Streptococcus mutans (S. mutans) were assessed. The HA-forming ability was evaluated by examining HA deposit on dentin surfaces after immersion in phosphate-buffered saline (PBS).

RESULTS

Characterization confirmed the successful synthesis of Ebselen/MBG-Ag and the uniform distribution of silver within the mesoporous matrix. Sustained release of silver ions and Ebselen was observed for up to 336 h. Compared with MBG-Ag alone, Ebselen/MBG-Ag exhibited significantly enhanced antibacterial and antibiofilm activities against E. faecalis and S. mutans. Furthermore, rapid HA formation was observed on treated dentin surfaces. In addition, Ebselen loading reduced the in vitro cytotoxicity of MBG-Ag, indicating improved cytocompatibility.

CONCLUSION

The incorporation of Ebselen into MBG-Ag enhanced antibacterial and antibiofilm activities endodontic pathogens, while promoting HA formation and reducing in vivo cytotoxicity. These findings suggest that Ebselen/MBG-Ag may serve as a candidate bioceramic material for future endodontic sealer development. Further long-term in vivo studies are warranted to confirm its biocompatibility, sealing performance, and clinical applicability.

CLINICAL RELEVANCE: The novel Ebselen/MBG-Ag bioceramic presents a dual-functional approach for endodontics. By simultaneously eliminating resilient bacterial biofilms and accelerating dentin remineralization via hydroxyapatite precipitation, it effectively targets the main drivers of root canal failure, offering a promising strategy to enhance long-term treatment success.