Relationship between and in early childhood caries, evaluated by quantitative PCR.

The aim of this study was to analyze the synergistic relationship between and in children with early childhood caries (ECC) experience. Dental plaque and unstimulated saliva samples were taken from 30 subjects aged 3-5 years old, half with (n=15, dmft > 4) and half without (n=15) ECC. The abundance of and and relative to total bacteria load were quantify by real-time PCR (qPCR). This method was also employed to investigate the mRNA expression of glycosyltransferase ( ) gene in dental plaque. Student's t-test and Pearson's correlation were used to perform statistical analysis. Within the ECC group, the quantity of both microorganisms were higher in the saliva than in dental plaque. The ratio of to total bacteria was higher in saliva than in plaque samples (p < 0.05). We observed the opposite for (p < 0.05). The different value of and in saliva was positively correlated, and negatively correlated in dental plaque. Transcription level of showed a positive correlation with concentration in dental plaque.  has a positive correlation with cariogenic traits of in ECC-related biofilm of young children.