Efficacy of Experimental Root Canal Irrigation Solution Against Enterococcus Faecalis

Objectives: To investigate the anti-microbial efficacy of an experimental root canal irrigation solution containing hydrolyzed copper and zinc and citric acid (Steriroot) on Enterococcus faecalis. Methods: This study was carried out at the South African Bureau of Standards. The root canals of 21 single rooted freshly extracted teeth were accessed with burs and prepared with stainless steel manual files and rotary NiTi files in a step-down procedure. The root canals were then sterilized and inoculated with Enterococcus faecalis and incubated anaerobically for 72 hours. Growth was confirmed by sampling with sterile paper points and plating the paper points onto brain heart infusion agar and anaerobic incubation for 72 hours.The teeth were then randomly divided into 3 groups of 7 teeth each. The root canals were then irrigated for 5 minutes using : Group 1: 50 ml 3.5% NaOCl Group 2: 50 ml of 1:50 dilution of Steriroot Group 3: 50 ml sterile water. The root canals were again sampled with paper points and the paper points plated onto brain heart infusion agar, incubated anaerobically for 72 hours and observed for growth. All teeth were dissected and prepared and viewed in SEM. Results: No growth was observed in Group 1. All samples from Groups 2 and 3 showed growth. A smear layer was observed in Groups 1 and 3. In Group 2 the smear layer was removed in some areas. Conclusion: Under the conditions of this study a 1:50 solution of Steriroot showed no anti-microbial efficacy against Enterococcus faecalis but it removed the smear layer more effectively than 3.5% NaOCl and sterile water.