title: Detection of cariogenic Streptococcus mutans by quantitative polymerase chain reaction.
abstract: OBJECTIVE
  To establish a kind of molecular biology clinical detective method to cariogenic S. mutans.
  
  
  METHODS
  Using the coamplification of target and reference genes. One pair of specific primers were designed according to a portion of the dextranase (dexA) gene of S. mutans. The reference gene was plasmid pET23b DNA. The saliva samples of 196 children were quantitative detected. The PCR method was compared with the routine culture method.
  
  
  RESULTS
  The rate of S. mutans counts >/= 10(8) CFU/L (colony-forming unit per millilitre) saliva by quantitative PCR was 91.3%. The results of coincidence rate between the new method and the routine way was 94.9%.
  
  
  CONCLUSIONS
  The new quantitative detective method is fast and provides with high scoincidence rate and high specificity, so have extensive clinical practice foreground.
authors.affiliation: Department of Dentistry, Beijing Chaoyang Hospital, Affiliate of Capital University of Medical Sciences, Beijing 100020, China.
authors.forename: Jianqiu
authors.initials: J
authors.lastname: Wang
authors.forename: Changyi
authors.initials: C
authors.lastname: Li
authors.forename: Bai
authors.initials: B
authors.lastname: Xiao
authors.forename: Jingzhong
authors.initials: J
authors.lastname: Liu
mesh_terms: D017931:DNA Primers; D006801:Humans; D016133:Polymerase Chain Reaction; D012463:Saliva; D012680:Sensitivity and Specificity; D013295:Streptococcus mutans / Q000235:genetics; D016986:Streptococcus sobrinus / Q000235:genetics
chemical_list: D017931:DNA Primers