Comparative evaluation of substantivity of two biguanides - 0.2% polyhexanide and 2% chlorhexidine on human dentin

Area of Science:

• Endodontics
• Dental Materials Science
• Antimicrobial Agents

Background:

• Substantivity, the ability to bind to tissues and retain activity, is a key characteristic for root canal irrigants.
• Chlorhexidine (CHX) is the only conventional endodontic irrigant known for significant substantivity on root canal dentin.
• This study investigates the substantivity of polyhexamethylene biguanide (PHMB), a polymeric biguanide.

Purpose of the Study:

• To determine the substantivity of 0.2% PHMB on root canal dentin.
• To compare the substantivity of 0.2% PHMB with 2% CHX.

Main Methods:

• Dentin disks were prepared for evaluation.
• Substantivity was measured using spectrophotometry at 1 hour, 24 hours, 7 days, and 21 days.
• Unpaired t-test was used for intergroup comparison.

Main Results:

• 0.2% PHMB exhibited significantly greater substantivity on human dentin compared to 2% CHX.
• The substantivity of PHMB was notably higher than CHX over the tested time points.

Conclusions:

• 0.2% polyhexanide (PHMB) shows enhanced substantivity on root canal dentin.
• PHMB's substantivity property supports its potential use as an effective endodontic irrigant.