IADR Abstract Archives

Diversity and stability of mutans streptococci genotype in children

It is well established that mutans streptococci (MS) are associated with the initiation of dental caries. A single MS genotype has been shown to colonize primary molars soon after eruption. More genotypes can be acquired with age and further dental development. Objectives: This study investigates the stability and diversity of MS genotypes in children as permanent molars (PMs) erupt. Methods: Ten children, 5-6 years old, had plaque collected from primary molars prior to eruption of at least one PM. Over a 6-month period when new PMs erupted, plaque samples were collected from primary and PMs, plated on Gold's media and grown anaerobically. Morphologically typical MS bacterial colonies were transferred to Todd Hewitt (TH) plates and single colonies (up to 10 each sample) were transferred into Todd Hewitt broth. DNA was extracted for use in repetitive extragenic palindromic-polymerase chain reaction (rep-PCR) (Bacterial Barcodes, Inc, Atlanta, GA) followed by microfluidics-based DNA amplicon fractionation and characterization using an Agilent 2100 Electrophoresis Bioanalyzer. The resulting data were analyzed by DiversiLab software (v3.3) using the Pearson correlation coefficient method to create DNA fingerprints of virtual gel images. Results: Among all 10 children, 9 different genotypes were identified. Two children had 1 genotype; Seven had 2 genotypes; One had 3 genotypes initially. At 6 months follow up, 1 genotype of 2 children was maintained and the other eight children's genotypes had changed by either introduction of new genotypes or loss of baseline genotypes. The changes in genotype were associated with new PM eruption. Conclusion: This data begins a longitudinal database of child follow-up to further pursue genotypic distribution within and between individual children and family members for evaluation how MS is transmitted and for the assessment of the risk for dental caries associated with diversity and stability of MS.

Supported by the NIDCR # DE016684


IADR/CADR General Session
2008 IADR/CADR General Session (Toronto, Ontario, Canada)
Toronto, Ontario, Canada
2008
15
Cariology Research
  • Cheon, Kyounga Cecilia  ( University of Alabama at Birmingham, Birmingham, AL, USA )
  • Moser, Stephen. A  ( University of Alabama at Birmingham, Birmingham, AL, USA )
  • Whiddon, Jennifer. F  ( University of Alabama at Birmingham, Birmingham, AL, USA )
  • Osgood, R. C  ( University of Alabama at Birmingham, Birmingham, AL, USA )
  • Momeni, Stephanie  ( University of Alabama at Birmingham, Birmingham, AL, USA )
  • Rahima, Bibi  ( University of Alabama at Birmingham, Birmingham, AL, USA )
  • Ruby, John. D  ( University of Alabama at Birmingham, Birmingham, AL, USA )
  • Childers, Noel K.  ( University of Alabama at Birmingham, Birmingham, AL, USA )
    • Oral Session
    Enamel/Microbiology/Genetics
    07/02/2008