title: Prevalence of four putative periodontopathic bacteria in saliva of a group of Brazilian children with mixed dentition: 1-year longitudinal study.
abstract: OBJECTIVE
  This study aimed at evaluating the prevalence of putative periodontal pathogens (Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella nigrescens, Treponema denticola) in saliva of children with mixed dentition at two different time points, correlating these findings with a clinical parameter of gingival health.
  
  
  METHODS
  Polymerase chain reaction (PCR) detection was used to determine the prevalence of these bacteria in saliva of 64 children in 2003 and 60 children in 2004. Gingival health was assessed by gingival index.
  
  
  RESULTS
  Sixty-two (96.9%) and 50 (83.3%) children presented low gingival inflammation, whereas 2 (3.1%) and 10 (16.7%) had moderate scores in 2003 and 2004, respectively. Majority of the children (81.3% in 2003 and 73.3% in 2004) had detectable levels of at least one of the bacteria. The prevalence found was of 4.7% and 1.7% for A. actinomycetemcomitans, 6.3% and 8.3% for P. gingivalis, 23.4% and 48.3% for P. nigrescens (P < 0.05), and 71.9% and 50% for T. denticola (P < 0.05) in 2003 and 2004, respectively. No significant relationship between gingival index and presence of these bacteria and combination of different species was found.
  
  
  CONCLUSIONS
  A high percentage of children harboured at least one of the putative periodontal pathogens in saliva, but presented periodontally healthy conditions.
authors.affiliation: Department of Pediatric Dentistry, Orthodontics and Public Health, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil.
authors.forename: Vivien T
authors.initials: VT
authors.lastname: Sakai
authors.forename: Marinele R
authors.initials: MR
authors.lastname: Campos
authors.forename: Maria Aparecida A M
authors.initials: MA
authors.lastname: Machado
authors.forename: José Roberto P
authors.initials: JR
authors.lastname: Lauris
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Greene
authors.forename: Carlos F
authors.initials: CF
authors.lastname: Santos
mesh_terms: D016976:Aggregatibacter actinomycetemcomitans / Q000302:isolation & purification; D001938:Brazil; D002648:Child; D015169:Colony Count, Microbial; D003818:Dentition, Mixed; D005260:Female; D005500:Follow-Up Studies; D005891:Gingivitis / Q000382:microbiology*; D006090:Gram-Negative Bacteria / Q000302:isolation & purification*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D010512:Periodontal Index; D016133:Polymerase Chain Reaction; D016966:Porphyromonas gingivalis / Q000302:isolation & purification; D045242:Prevotella nigrescens / Q000302:isolation & purification; D012463:Saliva / Q000382:microbiology*; D048373:Treponema denticola / Q000302:isolation & purification