Effectiveness of silver-graphene oxide nanoparticle against Enterococcus faecalis biofilms in the root canal.

Aim: This study aims to assess the effectiveness of silver-graphene oxide (AgGO) nanoparticles against Enterococcus faecalis biofilm and smear layer in comparison with 3% sodium hypochlorite (NaOCl) and 2% chlorhexidine (CHX) using passive ultrasonic irrigation (PUI) technique.

Subjects and methods: Eighty single-rooted teeth were collected, sterilized, and prepared for this study. E. faecalis was inoculated into the root canals and incubated for 21 days. Teeth were divided into four groups for irrigation: Group I (0.25% AgGO), Group II (3% NaOCl), Group III (2% CHX), and Group IV (0.9% saline), followed by PUI. Microbiological evaluation was performed by collecting bacterial samples and quantifying colony-forming units/ml. Scanning electron microscope was used to assess biofilm and smear layer removal.

Statistical analysis used: Kruskal-Wallis test, Bonferroni correction, intraclass correlation test.

Results: Antibacterial activity and smear layer removal were highest in Group II followed by Group I and Group III which showed similar results. Group IV showed the least results.

Conclusions: 3% NaOCl was the most effective solution in terms of antibacterial activity and smear layer removal. 0.25% AgGO and 2% CHX showed moderate effectiveness in removing E. faecalis biofilms and smear layer which suggests that both have potential as alternative irrigants.