Correlation of Streptococcus Mutans by 16SrRNA Gene Sequencing in Children with Different Caries Experience- A PCR Based Study

Abstract

Background and Objectives: Early Childhood Caries is considered as a common chronic disease in children. Since some research had concluded that children with higher levels of Streptococcus mutans are associated with a higher incidence of decayed, missing, and filled teeth, the present study was undertaken to analyze the salivary Streptococcus mutans of children with different caries status using species specific 16S rRNA gene sequencing technology to evaluate the quantity of Streptococcus mutans with respect to different caries status.
 Materials and Methods: Children between 3-6 years were selected and divided into 3 groups, Group I- Caries free, Group II-Early Childhood caries and Group III- Severe Early childhood caries. The caries status was assessed using dmfs and the severity of caries was assessed using pufa index. Salivary samples were collected to isolate DNA and Real time PCR was done with 16SrRNA primer specific to Streptococcus mutans to estimate the quantity of Streptococcus mutans in children with different caries status.
 Results: There was a significant difference in the mean CT values among the study groups (p < 0.001). Post hoc Tukey test revealed that, Group I had a significantly higher mean CT values than that of Groups II and III. Pearson's correlation analysis was carried out to correlate dmfs value with CT values and to correlate the pufa value with the fold change. There was a negative correlation between dmfs score and CT values and positive correlation between pufa score and fold change.
 Conclusion: There was a higher expression of 16SrRNA gene in Severe Early childhood caries group, followed by Early childhood caries and caries free group, indicating a high level of Streptococcus mutans in Severe Early childhood caries group and there was a negative correlation between dmfs score and CT values and a positive correlation between pufa score and fold change.