Antimicrobial residual effects of irrigation regimens with maleic acid in infected root canals

Area of Science:

• Endodontics
• Microbiology
• Dental Materials Science

Background:

• Endodontic treatment success relies on controlling root canal microorganisms.
• Enterococcus faecalis is a common pathogen in persistent endodontic infections.
• Investigating novel irrigation protocols is crucial for effective root canal disinfection.

Purpose of the Study:

• To evaluate the residual antimicrobial activity of 7% maleic acid (MA) alone and combined with chlorhexidine (CHX) and/or cetrimide (CTR).
• To assess the efficacy of these final irrigation protocols against Enterococcus faecalis biofilms in root canals.

Main Methods:

• Biofilms of E. faecalis were established in root canals over 4 weeks.
• 72 infected roots were divided into groups using final irrigation with 2.5% NaOCl, 7% MA, 7% MA + 0.2% CTR, 7% MA + 2% CHX, or 7% MA + 0.2% CTR + 2% CHX.
• Kaplan-Meier survival analysis and log-rank tests were used to compare the proportion of ungrown samples over 60 days.

Main Results:

• The combination of MA with CHX, and MA with CHX + CTR, demonstrated the highest efficacy, with 5 and 4 samples respectively showing no growth.
• 7% MA + 0.2% CTR showed moderate efficacy, with 7 out of 12 samples exhibiting no growth.
• 7% MA alone was significantly less effective, with 11 out of 12 samples showing growth, compared to MA combined with CHX or CHX + CTR.

Conclusions:

• Final irrigation protocols using 7% MA combined with 2% CHX or 2% CHX + 0.2% CTR significantly improve root canal disinfection.
• These combinations show superior antimicrobial activity against E. faecalis biofilms compared to MA alone.
• The findings support the use of these combined irrigants for enhanced endodontic treatment outcomes.