New intracanal formulations containing doxycycline or chlorhexidine against Enterococcus faecalis

Area of Science:

• Endodontics
• Microbiology
• Infectious Diseases

Background:

• Enterococcus faecalis (E. faecalis) is a common pathogen in persistent root canal infections.
• Effective intracanal medications are crucial for eliminating E. faecalis and ensuring endodontic treatment success.

Purpose of the Study:

• To evaluate the antimicrobial efficacy of two novel intracanal preparations against E. faecalis.
• To compare the effects of 3% doxycycline hydrochloride (DX) and 2% chlorhexidine digluconate (CHX) against E. faecalis in vitro.

Main Methods:

• Thirty single-rooted human canine teeth were instrumented and infected with E. faecalis.
• Teeth were treated with 3% DX gel, 2% CHX gel, or no medication (negative control).
• Microbial samples were collected after 14 days of medication and 7 days post-medication to quantify E. faecalis colony-forming units (CFU/ml).

Main Results:

• Both 3% DX and 2% CHX significantly reduced E. faecalis CFU/ml after 14 days of intracanal medication.
• Following medication removal, E. faecalis counts remained low in treated groups.
• The negative control group showed a significant increase in CFU/ml, returning to initial contamination levels.

Conclusions:

• 3% doxycycline hydrochloride gel and 2% chlorhexidine digluconate gel are effective in eliminating E. faecalis from the root canal system.
• These preparations demonstrate significant antimicrobial activity against E. faecalis, supporting their use in endodontic therapy.