Experimental abscess formation caused by human dental plaque

Area of Science:

• Microbiology
• Infectious Diseases
• Oral Health

Background:

• Human dental plaque harbors diverse microorganisms.
• Some plaque bacteria are implicated in systemic infections, including abscesses.
• The specific role of dental plaque in abscess formation requires experimental validation.

Purpose of the Study:

• To investigate the abscess-forming potential of native human dental plaque in a murine model.
• To characterize the microbial composition of induced abscesses.
• To assess the anti-phagocytic properties of isolated microorganisms.

Main Methods:

• Subcutaneous injection of supragingival dental plaque into mouse models.
• Isolation and identification of microorganisms from abscess lesions.
• Assessment of microbial anti-phagocytic capacity against human polymorphonuclear leukocytes.

Main Results:

• Dental plaque induced abscess formation in a significant majority of mice (76/85).
• Abscesses exhibited simplified microbial communities compared to the original plaque.
• The Streptococcus anginosus group, including S. anginosus, S. intermedius, and S. constellatus, were frequently isolated and identified as primary causative agents.
• Isolates demonstrated high anti-phagocytic properties.

Conclusions:

• Human supragingival dental plaque is a direct source of pathogens capable of causing abscess formation.
• The Streptococcus anginosus group plays a critical role in plaque-induced abscesses.
• The anti-phagocytic mechanism contributes to the virulence of these oral bacteria in systemic infections.