title: Effect of periodontal therapy on the subgingival microbiota over a 2-year monitoring period. I. Overall effect and kinetics of change.
abstract: OBJECTIVE
  To examine the 2-year post-therapy kinetics of change in the composition of subgingival biofilms.
  
  
  METHODS
  In this study, 178 chronic periodontitis subjects were recruited and clinically monitored at baseline, 3, 6, 12, 18 and 24 months after therapy. All subjects received scaling and root planing and 156 one or more of periodontal surgery, systemically administered amoxicillin + metronidazole or local tetracycline at pockets ≥5 mm. Subgingival biofilm samples taken from each subject at each time point were analysed for their content of 40 bacterial species using checkerboard DNA-DNA hybridization. The significance of changes in median species counts over time was sought using the Wilcoxon or Friedman tests and adjusted for multiple comparisons.
  
  
  RESULTS
  Mean counts were significantly reduced from baseline to 2 years for 30 of the 40 taxa. Marked reductions were observed for periodontal pathogens including Tannerella forsythia, Treponema denticola and Eubacterium nodatum. The kinetics of change differed from species to species. When data were subset according to baseline PD, patterns of change in the microbial profiles were generally similar.
  
  
  CONCLUSIONS
  Periodontal therapy leads to a rapid reduction in periodontal pathogens, followed by a slower reduction in other taxa that can be sustained for at least 2 years.
authors.affiliation: Department of Applied Oral Sciences, Center for Periodontology, The Forsyth Institute, Cambridge, MA, USA.
authors.forename: Sigmund S
authors.initials: SS
authors.lastname: Socransky
authors.forename: Anne D
authors.initials: AD
authors.lastname: Haffajee
authors.forename: Ricardo
authors.initials: R
authors.lastname: Teles
authors.forename: Jan L
authors.initials: JL
authors.lastname: Wennstrom
authors.forename: Jan
authors.initials: J
authors.lastname: Lindhe
authors.forename: Anna
authors.initials: A
authors.lastname: Bogren
authors.forename: Hatice
authors.initials: H
authors.lastname: Hasturk
authors.forename: Thomas
authors.initials: T
authors.lastname: van Dyke
authors.forename: Xiaoshan
authors.initials: X
authors.lastname: Wang
authors.forename: Jo Max
authors.initials: JM
authors.lastname: Goodson
mesh_terms: D000658:Amoxicillin / Q000008:administration & dosage / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D058491:Bacterial Load; D001439:Bacteroides / Q000302:isolation & purification; D018441:Biofilms / Q000145:classification*; D002206:Capnocytophaga / Q000302:isolation & purification; D055113:Chronic Periodontitis / Q000382:microbiology / Q000628:therapy*; D012534:Dental Scaling / Q000379:methods; D004338:Drug Combinations; D005051:Eubacterium / Q000302:isolation & purification; D005260:Female; D005500:Follow-Up Studies; D005673:Fusobacterium / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008795:Metronidazole / Q000008:administration & dosage / Q000627:therapeutic use; D008875:Middle Aged; D010514:Periodontal Pocket / Q000382:microbiology / Q000628:therapy; D018720:Prevotella / Q000302:isolation & purification; D011446:Prospective Studies; D016745:Root Planing / Q000379:methods; D016037:Single-Blind Method; D013291:Streptococcus / Q000302:isolation & purification; D013752:Tetracycline / Q000627:therapeutic use; D048373:Treponema denticola / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D004338:Drug Combinations; D008795:Metronidazole; D000658:Amoxicillin; D013752:Tetracycline
keywords: chronic periodontitis; kinetics; microbiology; therapy