title: Colonisation of the oral cavity by periodontopathic bacteria in complete denture wearers.
abstract: OBJECTIVE
  The purpose of this study was to investigate colonisation by periodontopathic bacteria and the sites of colonisation in elderly upper and lower complete denture wearers. We also investigated the relationship between level of oral hygiene and colonisation by periodontopathic bacteria.
  
  
  METHODS
  Forty edentulous and 37 dentate volunteers participated in this study. Samples were collected from whole saliva, and levels of Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia and Fusobacterium nucleatum were determined by PCR Invader technology. Detection of these species on oral mucosal and denture surfaces was performed by PCR. Fisher's exact test was used for the statistical analysis. Cluster analysis was employed to investigate trends in the periodontopathic bacteria flora in each sampling area.
  
  
  RESULTS
  Detection rates of periodontopathic bacteria in whole saliva were lower under edentulous conditions than under dentulous conditions, except for A. actinomycetemcomitans and F. nucleatum (p < 0.01). Detection rate of F. nucleatum was the highest in all areas. A positive correlation was observed between DNA quantification of P. gingivalis and number of Candida species in saliva. Cluster analysis of the test species identified two clusters. Tongue-coating status was associated with the detection rate of all periodontopathic bacteria investigated, and denture plaque status was associated with the detection rate of T. denticola and F. nucleatum.
  
  
  CONCLUSIONS
  Results indicate the presence of periodontopathic bacteria under edentulous conditions and that the status of oral hygiene of the mucosal or denture surfaces affects colonisation by T. denticola and F. nucleatum.
authors.affiliation: Oral Health Science Center, Tokyo Dental College, Mihama-ku, Chiba city, Chiba, Japan. ishihara@tdc.ac.jp
authors.forename: Masako
authors.initials: M
authors.lastname: Yasui
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ryu
authors.forename: Kaoru
authors.initials: K
authors.lastname: Sakurai
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Ishihara
mesh_terms: D000368:Aged; D016976:Aggregatibacter actinomycetemcomitans / Q000254:growth & development; D001422:Bacterial Adhesion; D001439:Bacteroides / Q000254:growth & development; D002175:Candida / Q000254:growth & development; D003773:Dental Plaque / Q000382:microbiology; D003817:Dentition; D003819:Denture Bases / Q000382:microbiology; D003824:Denture, Complete / Q000382:microbiology*; D003826:Denture, Complete, Lower / Q000382:microbiology; D003827:Denture, Complete, Upper / Q000382:microbiology; D005260:Female; D016967:Fusobacterium nucleatum / Q000254:growth & development; D006090:Gram-Negative Bacteria / Q000254:growth & development* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D009055:Mouth / Q000382:microbiology*; D009061:Mouth Mucosa / Q000382:microbiology; D009910:Oral Hygiene; D021362:Palate, Hard / Q000382:microbiology; D016966:Porphyromonas gingivalis / Q000254:growth & development; D018713:Prevotella intermedia / Q000254:growth & development; D012463:Saliva / Q000382:microbiology; D014059:Tongue / Q000382:microbiology; D014093:Tooth, Artificial / Q000382:microbiology; D048373:Treponema denticola / Q000254:growth & development