Polymerase chain reaction-based identification of various serotypes of Streptococcus mutans in adults with and without dental caries

Dental caries is a multistep process which initiates the development of plaque‚ defined as a structured biofilm containing microbial communities. Teeth provide unique surfaces for bacterial colonization. Serotypes of Streptococcus mutans implicate the development of dental caries. The aim of the study was to determine the prevalence and association of serotypes of S. mutans in groups with and without dental caries. One hundred and fifty adults aged between 18 and 35 years were included in the study. Supragingival plaque samples were collected, followed by deoxyribonucleic acid extraction. Polymerase chain reaction was performed to identify S. mutans and its serotypes. Proportions of S. mutans and its serotypes were correlated with caries-active (CA) and caries-free (CF) groups. CA group showed 66.7% positivity for S. mutans and CF group showed only 42.7% of positivity. Serotype C showed a higher proportion followed by E‚ F, and K in the CA group, whereas in the CF group, higher proportion was observed with K followed by C‚ E, and F. 70.8% cases showed single serotype in the CA group and 83.3% in CF group. Multiple serotypes were seen in 29.2% in the CA group and 16.7% in the CF group. The study clearly established variation in proportions of S. mutans and its serotypes between CA and CF groups. Positive correlation was observed in the CA group for S. mutans and its serotypes.