title: [Identification and quantitative analysis of Archaea involved in periodontal disease].
abstract: OBJECTIVE
  To make qualitative and quantitative analysis of Archaea in subgingival plaque sample and to investigate the relationship between periodontal disease and Archaea.
  
  
  METHODS
  Subgingival plaque was collected from 23 patients with aggressive periodontitis, 29 with chronic periodontitis, 35 with plaque-induced gingivitis and 38 healthy controls. Qualitative and quantitative analysis of methanogenic archaea was performed by amplification of the 16S rRNA genes in the DNA extracted from the plaque samples.
  
  
  RESULTS
  Archaea were found in 65% of aggressive periodontitis patients, 72% of chronic periodontitis, 26% of gingivitis and zero of healthy subjects. Quantitative analysis showed the average abundance of archaeal 16S rRNA gene in Archaea-positive patients was different among the three groups. The average 16S rRNA gene copy number from per microg wet plaque was 6.66 x 10(6) in aggressive periodontitis sufferers, 4.47 x 10(6) in chronic periodontitis and 1.78 x 10(6) in gingivitis groups. The prevalence of Archaea and the average Archaea 16S rRNA gene numbers in periodontitis groups were higher than those in gingivitis group (P < 0.05).
  
  
  CONCLUSIONS
  This suggests that Archaea may be implicated as causative agents for periodontitis.
authors.affiliation: Department of Oral Medicine, School of Stomatology, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200011, China.
authors.forename: Chao-lun
authors.initials: CL
authors.lastname: Li
authors.forename: Yun-tao
authors.initials: YT
authors.lastname: Jiang
authors.forename: Ming-zhu
authors.initials: MZ
authors.lastname: Zhang
authors.forename: Jing-ping
authors.initials: JP
authors.lastname: Liang
mesh_terms: D010520:Aggressive Periodontitis / Q000382:microbiology; D001105:Archaea / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D016022:Case-Control Studies; D055113:Chronic Periodontitis / Q000382:microbiology; D004269:DNA, Bacterial / Q000235:genetics; D003773:Dental Plaque / Q000382:microbiology*; D006801:Humans; D010510:Periodontal Diseases / Q000382:microbiology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S