title: Salivary mutans streptococci counts as indicators in caries risk assessment in 6-7-year-old Chinese children.
abstract: OBJECTIVE
  This study aimed to determine whether salivary mutans streptococci (MS) counts in Chinese children had any value in the prediction of new caries in the permanent dentition in the age interval of 6.5-8.5 years.
  
  
  METHODS
  Four hundred and thirty-three 6-7-year-old children participated in this 2-year longitudinal study. Salivary MS counts were obtained at baseline with the spatula method. Dentin and enamel caries was recorded at baseline and at the follow-up, 2 years later. Spearman's correlation coefficients were computed. Past caries experience variables at baseline were entered into a multiple regression model with caries increment of the permanent dentition as dependent variable. MS counts were subsequently entered into the model to assess the additional caries predictive value.
  
  
  RESULTS
  Spearman's correlation coefficient for MS counts and caries experience of the primary dentition at baseline was 0.48 and for MS counts and caries increment in the permanent dentition 0.12. In the multiple regression model caries increment of the permanent dentition had an adjusted R2 of 0.17 when the past caries experience variables were entered. Adding MS counts in the regression model did not change the R2 value.
  
  
  CONCLUSIONS
  Salivary MS counts did not add any caries predictive value when past caries experience variables were used as caries predictors in this Chinese child population.
authors.affiliation: Key Laboratory of Oral Biomedical Engineering, Ministry of Education and Department of Endodontics, School and Hospital of Stomatology, Wuhan University, Luoyu Road 237, Wuhan, Hubei Province 430079, PR China. zhangqimary@yahoo.com.cn
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.forename: Zhuan
authors.initials: Z
authors.lastname: Bian
authors.forename: Mingwen
authors.initials: M
authors.lastname: Fan
authors.forename: W H
authors.initials: WH
authors.lastname: van Palenstein Helderman
mesh_terms: D002648:Child; D002681:China; D015169:Colony Count, Microbial; D004245:DMF Index; D003731:Dental Caries / Q000382:microbiology* / Q000473:pathology; D003733:Dental Caries Susceptibility; D003743:Dental Enamel / Q000382:microbiology / Q000473:pathology; D003804:Dentin / Q000382:microbiology / Q000473:pathology; D005500:Follow-Up Studies; D005544:Forecasting; D006801:Humans; D008137:Longitudinal Studies; D018570:Risk Assessment; D012463:Saliva / Q000382:microbiology*; D013295:Streptococcus mutans / Q000302:isolation & purification*; D016986:Streptococcus sobrinus / Q000302:isolation & purification*; D014094:Tooth, Deciduous / Q000382:microbiology / Q000473:pathology