A Polysaccharide-Based Antibacterial Coating with Improved Durability for Clear Overlay Appliances

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Orthodontics

Background:

• Clear overlay appliances (COAs) are popular in orthodontics due to their cost-effectiveness and aesthetics.
• Current COAs made from thermoplastic polymers suffer from poor durability and bacterial accumulation, necessitating frequent replacement.
• There is a need for improved materials to enhance the performance and lifespan of COAs.

Purpose of the Study:

• To develop durable, antibacterial multilayer films for clear overlay appliance (COA) applications.
• To improve the mechanical properties and reduce bacterial adhesion on COA materials.
• To explore the potential of polysaccharide-based coatings for enhanced intraoral device performance.

Main Methods:

• Fabrication of carboxymethylcellulose (CMC) and chitosan (CHI) multilayer films on PETG using a layer-by-layer (LbL) technique.
• Introduction of chemical cross-linking within the LbL-assembled CMC/CHI films.
• Evaluation of surface properties, bacterial reduction ratio, chemical resistance, and mechanical stability under simulated intraoral conditions.

Main Results:

• The cross-linked CMC/CHI multilayer films exhibited a superhydrophilic surface, preventing bacterial adhesion.
• A significant bacterial reduction ratio of approximately 75% was achieved.
• Cross-linking enhanced the chemical resistance and mechanical stability of the PETG substrate by strengthening inter-chain bonds.

Conclusions:

• Polysaccharide-based antibacterial multilayer films offer a promising solution for improving COA durability and hygiene.
• The developed LbL films with chemical cross-linking significantly enhance material properties for intraoral applications.
• This approach provides a foundation for developing next-generation COAs with improved patient outcomes.