title: Distribution of selected cariogenic bacteria in five different intra-oral habitats in young children.
abstract: BACKGROUND
  Knowledge of the colonization patterns and composition of the oral microbiota can lead to a better understanding of disease initiation.
  
  
  OBJECTIVE
  The aim of this study was to examine the distribution of selected cariogenic bacteria in samples from five different oral habitats in young Greek children.
  
  
  METHODS
  Ninety-three children 3-12 years old (mean + SD 7.9 +/- 2.5) (60.2% male, 39.8% female) participated and split into three different age groups: primary (3-6 years), early mixed (6-9 years), and mixed dentition (9-12 years). Samples for bacterial enumeration were taken from saliva, supragingival and subgingival plaque, tongue dorsum, and soft tissues from each child, and were further analysed using checkerboard DNA-DNA hybridization.
  
  
  RESULTS
  Mean counts and proportions of all the test bacteria differed significantly among sample locations. Cariogenic bacteria were present in almost all healthy children. Mean proportions of Streptococcus mutans isolated from soft tissue and Streptococcus sanguinis from soft tissue, subgingival and saliva samples increased significantly with age, whereas the opposite was seen for Lactobacillus acidophilus.
  
  
  CONCLUSIONS
  Cariogenic bacteria were present in almost all young children. Soft tissues, saliva, and tongue were more often colonized by cariogenic streptococcal species than teeth. These surfaces may serve as reservoirs for oral pathogens, requiring attention during preventive interventions.
authors.affiliation: Department of Padiatric Dentistry, University of Athens, Athens, Greece. periowp@hol.gr
authors.forename: Sotiria
authors.initials: S
authors.lastname: Gizani
authors.forename: William
authors.initials: W
authors.lastname: Papaioannou
authors.forename: Anne D
authors.initials: AD
authors.lastname: Haffajee
authors.forename: Katerina
authors.initials: K
authors.lastname: Kavvadia
authors.forename: Marc
authors.initials: M
authors.lastname: Quirynen
authors.forename: Liza
authors.initials: L
authors.lastname: Papagiannoulis
mesh_terms: D000190:Actinomyces / Q000302:isolation & purification; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D015169:Colony Count, Microbial; D004245:DMF Index; D003731:Dental Caries / Q000382:microbiology*; D003773:Dental Plaque / Q000382:microbiology; D003818:Dentition, Mixed; D005260:Female; D006115:Greece; D006801:Humans; D007779:Lactobacillus acidophilus / Q000302:isolation & purification; D008297:Male; D009055:Mouth / Q000382:microbiology*; D009061:Mouth Mucosa / Q000382:microbiology; D042807:Neisseria mucosa / Q000302:isolation & purification; D009693:Nucleic Acid Hybridization; D012463:Saliva / Q000382:microbiology; D013291:Streptococcus / Q000145:classification / Q000302:isolation & purification*; D034361:Streptococcus mitis / Q000302:isolation & purification; D013295:Streptococcus mutans / Q000302:isolation & purification; D019533:Streptococcus oralis / Q000302:isolation & purification; D014059:Tongue / Q000382:microbiology; D014094:Tooth, Deciduous / Q000382:microbiology; D014678:Veillonella / Q000302:isolation & purification