E-Book 3rd Congress

  • Investigating the presence of Streptococcus mutans through oral saliva by polymerase chain reaction method
  • Hafezeh Azizi,1,* Farnaz Farzaneh Dehkordi,2
    1. Islamic Azad university ardabil
    2. Islamic Azad university


  • Introduction: Many infectious diseases in humans are caused by virulent biofilms. Tooth decay is one of the most important diseases related to biofilm in the world. Streptococcus mutans cocci is gram-positive and facultative anaerobes, which is the flora of the oral cavity in humans and is the main bacteria that causes caries. The caries process directly depends on the ability of microorganisms to colonize on the tooth surface and form plaque. (S. mutans) determination in saliva is recommended as a suitable method in contrast to phenotypic and culture methods to identify patients at risk of dental caries. The main purpose of this research is to investigate the presence of Streptococcus mutans through oral saliva by polymerase chain reaction method as a fast, simple, cheap and non-invasive method.
  • Methods: Materials and methods: In this study on DNA extracted from case and control samples, quantity and quality assessment DNA was performed by nanodrab in order to detect Streptococcus Motense, Polymerase Chain Reaction (PCR) with dedicated htrA Protease Serin Protease Primers, and the results were analyzed by SPSS software and under the Cai Square test.
  • Results: Results: Among 66 people with caries, 59 people had positive PCR test for Streptococcus mutans, 24 of them were men and 25 were women. Also, 18 people (10 women and 8 men) from the normal population tested had a positive PCR test for Streptococcus mutans.
  • Conclusion: In this study, a significance level of 0.05 was considered, and higher values (P-value>0.05) reject the existence of a relationship between two variables, and lower values (P-value<0.05) confirm the existence of a relationship between two variables. slow down According to the results obtained by the square test (P-value=0.259), there is no significant relationship between caries and gender, and the correlation coefficient (R) (P-value=0.000) shows a relatively strong and positive relationship between the presence of Streptococcus mutans in the cavity. It shows mouth and tooth decay. So this method can be a method with high sensitivity and specificity.
  • Keywords: Bacteria, PCR, Streptococcus mutans,tooth decay, oral saliva