title: Periodontopathic bacterial infection in childhood.
abstract: BACKGROUND
  Little information is available on periodontopathic bacterial infection in childhood. We assessed the prevalence by age of 10 putative periodontopathic microorganisms in periodontally healthy children using a polymerase chain reaction (PCR) assay.
  
  
  METHODS
  Plaque samples were collected from the buccal-mesial sulcus of the first molar or second primary molar in the right upper quadrant of 144 children (2 to 13 years old, 12 subjects from each year of age) who showed negligible periodontal inflammation. Using species-specific primers of Porphyromonas gingivalis, Bacteroides forsythus, Prevotella intermedia, Prevotella nigrescens, Campylobacter rectus, Eikenella corrodens, Actinobacillus actinomycetemcomitans, Capnocytophaga ochracea, Capnocytophaga sputigena, and Treponema denticola, PCR amplification was performed with bacterial genomic DNA from plaque samples.
  
  
  RESULTS
  The results indicated that C. rectus, E. corrodens, A. actinomycetemcomitans, C. ochracea, and C. sputigena were found in about 50% of the plaque samples from all age groups, while B. forsythus and P. intermedia were detected less frequently, and P. gingivalis and T. denticola were not found. In contrast, the percentage of P. nigrescens-positive subjects increased with age in primary dentition, and reached about 50% at 7 years of age and older. Subject-based analyses suggested that the number of bacterial species in the plaque samples increased gradually with age until 5 years old, and then reached a plateau after the mixed dentition period.
  
  
  CONCLUSIONS
  The colonization of many putative periodontopathic microorganisms can occur quite early in childhood without clinical signs of periodontal disease. However, colonization by P. gingivalis and T. denticola was not detected in periodontally healthy children.
authors.affiliation: Department of Oral Microbiology, Iwate Medical University School of Dentistry, Morioka, Japan. kimuras@iwate-med.ac.jp
authors.forename: Shigenobu
authors.initials: S
authors.lastname: Kimura
authors.forename: Takashi
authors.initials: T
authors.lastname: Ooshima
authors.forename: Miyako
authors.initials: M
authors.lastname: Takiguchi
authors.forename: Yumi
authors.initials: Y
authors.lastname: Sasaki
authors.forename: Atsuo
authors.initials: A
authors.lastname: Amano
authors.forename: Ichijiro
authors.initials: I
authors.lastname: Morisaki
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Hamada
mesh_terms: D000189:Actinobacillus Infections / Q000175:diagnosis; D000293:Adolescent; D000367:Age Factors; D016976:Aggregatibacter actinomycetemcomitans / Q000145:classification; D016866:Bacteroidaceae Infections / Q000175:diagnosis; D001439:Bacteroides / Q000145:classification; D001442:Bacteroides Infections / Q000175:diagnosis; D002167:Campylobacter / Q000145:classification; D002169:Campylobacter Infections / Q000175:diagnosis; D002206:Capnocytophaga / Q000145:classification; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D003773:Dental Plaque / Q000382:microbiology; D003818:Dentition, Mixed; D016124:Eikenella corrodens / Q000145:classification; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000175:diagnosis*; D006801:Humans; D008297:Male; D010510:Periodontal Diseases / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D016966:Porphyromonas gingivalis / Q000145:classification; D018720:Prevotella / Q000145:classification; D018713:Prevotella intermedia / Q000145:classification; D014094:Tooth, Deciduous / Q000382:microbiology; D014208:Treponema / Q000145:classification; D014211:Treponemal Infections / Q000175:diagnosis