Streptococcus Mutans - Ecology

Ecology

Twenty-five species of oral streptococci live in the oral cavity. Each species has developed specific specialized properties for colonizing different oral sites and constantly changing conditions to fight competing bacteria and to withstand external challenges. Imbalances in the microbial biota can initiate oral diseases. Under special conditions, commensal streptococci can switch to opportunistic pathogens, initiating disease and damaging the host. Oral streptococci has both harmless and harmful bacteria. "Mutans streptococci" are the most important bacteria associated with tooth decay. S. mutans, the microbial species most strongly associated with carious lesions, is naturally present in the human oral microbiota. The taxonomy of these complex bacteria remains tentative. A 1970’s study found that S. mutans was more prevalent on the pits and fissures, constituting 39% of the total streptococci in the oral cavity. Fewer S. mutans were found on the buccal surface (2-9%).