Streptococcus Mutans Reactive Oxygen Species Metabolism And Its Significance In Causing Dental Caries

Dental caries are commonly and frequently encountered oral diseases and streptococcus mutans is regarded as the main pathogenic bacterium in causing dental caries. Dental plaque, in which streptococcus mutans could grow and cause dental caries, is a cariogenic environment. Previous studies stated that dental caries is caused by electrochemical corrosiveness and redox potential changes in the dental plaque is the main factor incausing dental caries. My colleagues and I had proved that redox potential in the dental plaque is negative and reactive oxygen species is the reason of negative potential formation. In order to research for the origin of active oxygen in the dental plaque, following three studies were done:1. A general study on streptococcus mutans reactive oxygen species metabolism.2. The effect of exogenous sugar on streptococcus mutans reactive oxygen species metabolism.3. A preliminary study on the mechanism of streptococcus mutans reactive oxygen species formation.Following results were obtained:1. Electron spin resonance (ESR) spectrum of DMPO-O₂^·|- and DMPO - OH· And superoxide dismutase were obtained in streptococcus mutans culture fluid. This result proved that streptococcus mutans could produce reactive oxygen species and have active oxygen scavenging systems.