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Related Experiment Video

Updated: Apr 14, 2026

3D Imaging of PDL Collagen Fibers during Orthodontic Tooth Movement in Mandibular Murine Model

3D Imaging of PDL Collagen Fibers during Orthodontic Tooth Movement in Mandibular Murine Model

Published on: April 15, 2021

Chlorhexidine-releasing orthodontic elastomerics.

Hyun-Sun Jeon¹, Choong-Ho Choi, Si-Mook Kang

¹Department of Preventive Dentistry and Public Oral Health, Yonsei University College of Dentistry.

Dental Materials Journal

|April 24, 2015

Summary

This study found the optimal chlorhexidine (CHX) and ethyl cellulose combination for sustained antimicrobial release from orthodontic elastomerics. Group 3 demonstrated superior sustained release and antibacterial activity without compromising material integrity.

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Area of Science:

Materials Science
Biomaterials Engineering
Orthodontics

Background:

Orthodontic patients are susceptible to oral diseases.
Chlorhexidine (CHX) is a potent antimicrobial agent.
Elastomeric ligatures in orthodontics can harbor bacteria.

Purpose of the Study:

To determine the optimal combination of chlorhexidine (CHX) with ethyl cellulose (EC) for sustained release from orthodontic elastomerics.
To evaluate the impact of different solvents on CHX release and antimicrobial efficacy.
To assess the mechanical properties of CHX-coated elastomerics.

Main Methods:

Coating orthodontic elastomerics with ethyl cellulose and chlorhexidine using various solvents (ethanol, dichloromethane).
Evaluating chlorhexidine release kinetics using UV spectrophotometry over 48 hours.
Assessing antimicrobial properties via inhibition zone testing against *S. mutans*.
Analyzing surface morphology with Scanning Electron Microscopy (SEM).
Testing tensile force to evaluate mechanical integrity.

Main Results:

Group 3 (CDA+EC+30% EtOH/70% DCM) exhibited the longest sustained chlorhexidine release over 48 hours (p<0.001).
This group also demonstrated the highest antimicrobial efficacy against *S. mutans* (p<0.05).
Coating did not negatively affect the tensile force of the orthodontic elastomerics.

Conclusions:

The sustained release and antimicrobial properties of chlorhexidine can be modulated by polymer and solvent selection.
The combination of ethyl cellulose with a 30% ethanol/70% dichloromethane solvent system (Group 3) provides optimal substantivity and antimicrobial activity for orthodontic applications.