Detection of Streptococcus mutans in human saliva and plaque using selective media, polymerase chain reaction, and monoclonal antibodies

Abstract

The objective of this study was to evaluate the distribution of dental caries-associated Streptococcus mutans in human saliva and plaque. The samples for this study were collected from 90 subjects (30 children, 30 adolescents, and 30 adults). The decayed, missing, and filled teeth (DMFT) and significant caries indices were evaluated. We applied polymerase chain reaction (PCR) analysis to detect S. mutans in each sample. Enumeration of S. mutans was conducted through culturing on Dentocult-SM and mitis salivarius agar medium. For saliva samples enzyme-linked immunosorbent assay (ELISA) analysis using monoclonal antibodies specific to antigen I/II and glucosyltransferase was done. We detected S. mutans in 79.7% and 56.8% of all saliva and plaque samples, respectively using PCR analyses. S. mutans were detected in 59.1%, 88.0%, and 88.9%, and in 86.4%, 56.0%, and 33.3% of saliva and plaque samples from children, adolescents, and adults, respectively. There were significantly higher levels of S. mutans in adolescents’ saliva more than any groups. There was a positive correlation between DMFT and the level of S. mutans reactivity measured using ELISA. Our results suggest that there should be more emphasis on adolescents’ oral hygiene more than in children or adults early prevention and research of dental caries.