Chlorhexidine hexametaphosphate as a coating for elastomeric ligatures with sustained antimicrobial properties: A...

Area of Science:

• Biomaterials Science
• Dental Materials
• Orthodontic Materials

Background:

• White spot lesions are a prevalent complication of orthodontic therapy.
• Developing effective strategies for their prevention is crucial.
• This study investigates a novel coating for orthodontic elastomeric ligatures.

Purpose of the Study:

• To evaluate the suitability of chlorhexidine hexametaphosphate (CHX-HMP) as a coating for orthodontic elastomeric ligatures.
• To assess the sustained release of chlorhexidine (CHX) from these coated ligatures.
• To determine the impact of conditioning methods on CHX release and ligature properties.

Main Methods:

• CHX-HMP dissolution kinetics were analyzed using spectroscopy and a colorimetric phosphate assay.
• Elastomeric ligatures were conditioned (acetone, ethanol, or as received) and immersed in CHX-HMP or chlorhexidine digluconate.
• CHX release was measured over 8 weeks, with mechanical properties and surface topography assessed.

Main Results:

• CHX-HMP demonstrated gradual release of soluble CHX and phosphates over 8 weeks.
• Ethanol conditioning significantly enhanced CHX-HMP uptake (6x) and led to sustained CHX release.
• Acetone conditioning did not improve CHX release and negatively impacted mechanical properties; CHX digluconate treatment showed no release.

Conclusions:

• Ethanol conditioning of CHX-HMP coated elastomeric ligatures facilitates sustained CHX release.
• This in-vitro study suggests potential for coated ligatures in preventing orthodontic white spot lesions.
• Further clinical investigations are warranted to confirm efficacy in patients.