Randomised Controlled Trial on the Additive Effect Between Calcium Hydroxide and Sodium Hypochlorite in an...

Area of Science:

• Endodontics
• Microbiology
• Biochemistry

Background:

• Apical periodontitis presents a significant endodontic challenge.
• Effective intracanal disinfection is crucial for treatment success.
• Investigating novel antimicrobial strategies for root canal therapy is ongoing.

Purpose of the Study:

• To evaluate the additive antimicrobial efficacy of calcium hydroxide (Ca(OH)₂) combined with sodium hypochlorite (NaOCl) as an inter-visit root canal dressing.
• To compare the microbial reduction achieved by Ca(OH)₂/NaOCl slurry versus Ca(OH)₂/saline slurry.
• To assess the impact on periapical inflammatory markers.

Main Methods:

• A randomized controlled clinical trial involving patients with pulpal necrosis and apical periodontitis.
• Root canals were instrumented and irrigated with 3% NaOCl.
• Inter-visit dressings consisted of Ca(OH)₂ slurry mixed with either 3% NaOCl (test) or saline (control).
• Microbial samples and periapical fluid were collected for analysis of anaerobic growth and MMP-9 levels.

Main Results:

• The Ca(OH)₂/NaOCl group showed significantly higher rates of microbial elimination (40%) compared to the Ca(OH)₂/saline group (6%) (p<0.001).
• Chemo-mechanical preparation significantly reduced colony-forming units (CFUs) but did not achieve complete microbial eradication.
• Matrix metalloproteinase-9 (MMP-9) levels in periapical fluid were comparable between the test and control groups.

Conclusions:

• A combined NaOCl/Ca(OH)₂ root canal dressing demonstrates superior antimicrobial activity against bacteria in primary apical periodontitis.
• This enhanced disinfection was achieved without an apparent increase in periapical inflammation.
• The findings support the use of NaOCl-augmented Ca(OH)₂ dressings for improved endodontic disinfection.