IADR Abstract Archives
Phage Therapy Against VRE Periapical Infections in Rats
Objectives: Enteroccocus faecalis (E. faecalis) is the third most prevalent nosocomial pathogen worldwide. Among the Enterococci, E. faecalis is responsible for 80-90% of the infections. Vancomycin-resistant enterococci (VRE) were declared by the CDC as one of the most difficult organisms to treat. E. faecalis is frequently recovered from secondary persistent infections associated with root canal treatment failures. A possible solution to target resistant bacteria is phage therapy. Phages are viruses that target bacteria and are considered as bacterial "professional killers". Their specificity and penetration modalities make them ideal for targeting bacteria in the pulp chamber and in the periapical tissue. We isolated efficient phages against VRE known as EFDG1 and EFLK1. The null hypothesis here was that local treatment of phages cocktail could kill VRE in periapical infection and decrease the periapical lesion.
Methods: Periapical lesions were induced by VRE in root canal infection model on incisor teeth of male rats. Root canals were instrumented and irrigated in a standard procedure. Test group included irrigation with phage cocktail. Microbiological samples were collected before and 3 weeks after treatment evaluating bacterial number (CFU/mL), and the DNA of bacteria from the root canal were isolated. Three weeks after treatment periapical lesions were evaluated using microCT, scanning electron microscopy and histology. In addition, the changes in the microbiota of the root canals were evaluated using 16S genome sequencing and light microscopy.
Results: Viable counts of VRE showed a significant killing of E. faecalis (3 logs growth reduction). 16S and light microscopy analysis showed that the phages cocktail changed the microbiota of the root canal, reducing the number of E. faecalis. MicroCT showed reduction in the periapical lesion size following phages treatment. Moreover, reduction in the inflammation of the periapical tissue was depicted using SEM and histological analysis.
Conclusions: Phage therapy is an efficient treatment against VRE in root canal periapical lesions in rat model.
Methods: Periapical lesions were induced by VRE in root canal infection model on incisor teeth of male rats. Root canals were instrumented and irrigated in a standard procedure. Test group included irrigation with phage cocktail. Microbiological samples were collected before and 3 weeks after treatment evaluating bacterial number (CFU/mL), and the DNA of bacteria from the root canal were isolated. Three weeks after treatment periapical lesions were evaluated using microCT, scanning electron microscopy and histology. In addition, the changes in the microbiota of the root canals were evaluated using 16S genome sequencing and light microscopy.
Results: Viable counts of VRE showed a significant killing of E. faecalis (3 logs growth reduction). 16S and light microscopy analysis showed that the phages cocktail changed the microbiota of the root canal, reducing the number of E. faecalis. MicroCT showed reduction in the periapical lesion size following phages treatment. Moreover, reduction in the inflammation of the periapical tissue was depicted using SEM and histological analysis.
Conclusions: Phage therapy is an efficient treatment against VRE in root canal periapical lesions in rat model.