Enterococcus faecalis--a mechanism for its role in endodontic failure.

Area of Science:

• Microbiology
• Endodontics
• Dental Research

Background:

• * Enterococcus faecalis (E. faecalis) is a common bacterium found in failed endodontic treatments.
• * Understanding its survival mechanisms within dentinal tubules is crucial for effective treatment.
• * Dentinal tubules offer a protected environment for bacterial persistence.

Purpose of the Study:

• * To investigate the mechanism of E. faecalis survival and growth within dentinal tubules.
• * To determine if E. faecalis can reinfect an obturated root canal.
• * To assess the role of human serum in E. faecalis's ability to invade dentine and bind to collagen.

Main Methods:

• * E. faecalis, Streptococcus gordonii, and Streptococcus mutans were cultured in human serum for 56 days.
• * Dentine invasion assays were performed.
• * Microtitre well experiments assessed bacterial binding to immobilized type I collagen.

Main Results:

• * All tested bacteria remained viable in human serum.
• * E. faecalis showed enhanced collagen binding and reduced, but not inhibited, dentine invasion in the presence of serum.
• * Human serum inhibited dentine invasion and collagen adhesion in S. gordonii and S. mutans.

Conclusions:

• * E. faecalis's ability to invade dentinal tubules and adhere to collagen in human serum is a potential virulence factor.
• * This resilience may contribute to the persistence of E. faecalis in endodontically treated teeth.
• * Further research into these mechanisms could lead to improved endodontic therapies.