An in vitro dynamic bioreactor model for evaluating antimicrobial effectiveness on periodontal polymicrobial...

Area of Science:

• Microbiology
• Pharmacology
• Biotechnology

Background:

• Subgingival plaque harbors polymicrobial biofilms contributing to periodontal diseases.
• Understanding antimicrobial efficacy against these biofilms is crucial for effective treatment.

Purpose of the Study:

• To evaluate the antimicrobial impact of amoxicillin on oral polymicrobial biofilms using a dynamic in vitro model.
• To simulate clinically relevant amoxicillin dosing within a bioreactor system.

Main Methods:

• Oral microcosm biofilms were cultivated in dynamic biofilm reactors for 108 hours.
• Amoxicillin was administered to simulate a 500 mg thrice-daily regimen over 5 days.
• Biofilms were analyzed using live/dead staining, SEM, and qPCR.

Main Results:

• Amoxicillin treatment significantly increased dead bacteria in biofilms at multiple time points (p < 0.0140).
• Viable bacteria persisted in biofilm centers despite treatment.
• Significant reductions in key periodontal pathogens like C. rectus and T. forsythia were observed.

Conclusions:

• The developed in vitro dynamic model successfully simulated the antimicrobial effects of clinically relevant amoxicillin doses.
• This model provides a valuable tool for studying antibiotic efficacy against complex oral biofilms.