Effect of silver-loaded PMMA on Streptococcus mutans in a drip flow reactor

Area of Science:

• Biomaterials Science
• Dental Materials
• Microbiology

Background:

• Orthodontic retainers are essential for maintaining tooth alignment but pose a risk for bacterial colonization and caries.
• Streptococcus mutans is a primary contributor to caries formation in the oral environment.
• Silver incorporation into biomaterials is explored for its antimicrobial properties.

Purpose of the Study:

• To evaluate the long-term efficacy of silver-containing base plate materials against Streptococcus mutans biofilm formation.
• To assess the impact of prolonged washout periods on the antimicrobial properties of silver-infused materials.

Main Methods:

• Silver was incorporated into base plate materials.
• Materials underwent short-term or long-term washout periods.
• Biofilm formation of Streptococcus mutans was assessed using a drip flow reactor simulating oral conditions.

Main Results:

• Silver-containing materials effectively resisted Streptococcus mutans biofilm formation after short-term washout.
• Long-term washout significantly reduced the materials' ability to inhibit biofilm formation.
• The antimicrobial efficacy of silver is compromised over extended periods under simulated oral conditions.

Conclusions:

• The antimicrobial benefit of silver in orthodontic base plate materials is time-dependent and diminishes with prolonged washout.
• Future development of antimicrobial orthodontic materials requires consideration of long-term efficacy and washout effects.
• Strategies to ensure sustained antimicrobial activity are needed to reduce caries risk in patients using orthodontic retainers.