title: Progression of chronic periodontitis can be predicted by the levels of Porphyromonas gingivalis and Treponema denticola in subgingival plaque.
abstract: BACKGROUND
  Chronic periodontitis is an inflammatory disease of the supporting tissues of the teeth associated with bacteria. Diagnosis is achieved retrospectively by clinical observation of attachment loss. Predicting disease progression would allow for targeted preventive therapy. The aim of this study was to monitor disease progression in patients on a maintenance program and determine the levels of specific bacteria in subgingival plaque samples and then examine the ability of the clinical parameters of disease and levels of specific bacteria in the plaque samples to predict disease progression.
  
  
  METHODS
  During a 12-month longitudinal study of 41 subjects, 25 sites in 21 subjects experienced disease progression indicated by at least 2 mm of clinical attachment loss. Real-time polymerase chain reaction was used to determine the levels of Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, Fusobacterium nucleatum, and Prevotella intermedia in subgingival plaque samples.
  
  
  RESULTS
  No clinical parameters were able to predict periodontal disease progression. In sites undergoing imminent periodontal disease progression within the next 3 months, significant partial correlations were found between P. gingivalis and T. forsythia (r = 0.55, P < 0.001) and T. denticola and T. forsythia (r = 0.43, P = 0.04). The odds of a site undergoing imminent periodontal disease progression increased with increasing levels of P. gingivalis and T. denticola.
  
  
  CONCLUSIONS
  Monitoring the proportions of P. gingivalis and T. denticola in subgingival plaque has the potential to help identify sites at significant risk for progression of periodontitis, which would assist in the targeted treatment of disease.
authors.affiliation: Cooperative Research Centre for Oral Health Science, Melbourne Dental School and Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Melbourne, Vic., Australia.
authors.forename: S J
authors.initials: SJ
authors.lastname: Byrne
authors.forename: S G
authors.initials: SG
authors.lastname: Dashper
authors.forename: I B
authors.initials: IB
authors.lastname: Darby
authors.forename: G G
authors.initials: GG
authors.lastname: Adams
authors.forename: B
authors.initials: B
authors.lastname: Hoffmann
authors.forename: E C
authors.initials: EC
authors.lastname: Reynolds
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D055113:Chronic Periodontitis / Q000473:pathology*; D004269:DNA, Bacterial / Q000032:analysis; D003773:Dental Plaque / Q000382:microbiology*; D003774:Dental Plaque Index; D018450:Disease Progression; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010512:Periodontal Index; D010514:Periodontal Pocket / Q000382:microbiology; D016966:Porphyromonas gingivalis / Q000302:isolation & purification*; D011379:Prognosis; D048373:Treponema denticola / Q000302:isolation & purification*
chemical_list: D004269:DNA, Bacterial