title: Changes in salivary periodontal pathogens after orthodontic treatment: An in vivo prospective study.
abstract: OBJECTIVE
  To analyze the initial changes in salivary levels of periodontal pathogens after orthodontic treatment with fixed appliances.
  
  
  METHODS
  The subjects consisted of 54 adult patients. The Simplified Oral Hygiene Index, Plaque Index, and Gingival Index were measured as periodontal parameters. Both the plaque and gingival indexes were obtained from the central and lateral incisors and first molars of both arches. Whole saliva and periodontal parameters were obtained at the following four time points: immediately before debonding (T1), 1 week after debonding (T2), 5 weeks after debonding (T3), and 13 weeks after debonding (T4). Repeated measures analysis of variance was used to determine salivary bacterial levels and periodontal parameters among the four time points after quantifying salivary levels of Aggregatibacter actinomycetemcomitans (Aa), Fusobacterium nucleatum (Fn), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Tannerella forsythia (Tf), and total bacteria using the real-time polymerase chain reaction.
  
  
  RESULTS
  All periodontal parameters were significantly decreased immediately after debonding (T2). The salivary levels of total bacteria and Pg were decreased at T3, while Pi and Tf levels were decreased at T4. However, the amount of Aa and Fn remained at similar levels in saliva during the experimental period. Interestingly, Aa and Fn were present in saliva at higher levels than were Pg, Pi, and Tf.
  
  
  CONCLUSIONS
  The higher salivary levels of Aa and Fn after debonding suggests that the risk of periodontal problems cannot be completely eliminated by the removal of fixed orthodontic appliances during the initial retention period, despite improved oral hygiene.
authors.affiliation: Graduate Student, Dental Research Institute and Department of Oral Microbiology and Immunology, School of Dentistry, Seoul National University, Seoul, Korea.
authors.forename: Kyungsun
authors.initials: K
authors.lastname: Kim
authors.affiliation: Clinical Lecturer, Department of Orthodontics, Seoul National University Gwanak Dental Hospital, Seoul, Korea.
authors.forename: Woo-Sun
authors.initials: WS
authors.lastname: Jung
authors.affiliation: Research Assistant, Dental Research Institute, Seoul National University, Seoul, Korea.
authors.forename: Soha
authors.initials: S
authors.lastname: Cho
authors.affiliation: Professor, Dental Research Institute and Department of Orthodontics, School of Dentistry, Seoul National University, Seoul, Korea.
authors.forename: Sug-Joon
authors.initials: SJ
authors.lastname: Ahn
mesh_terms: D000328:Adult; D016976:Aggregatibacter actinomycetemcomitans; D001419:Bacteria / Q000302:isolation & purification*; D003773:Dental Plaque / Q000382:microbiology*; D005260:Female; D016967:Fusobacterium nucleatum; D006801:Humans; D008297:Male; D009967:Orthodontic Appliances; D010512:Periodontal Index; D016966:Porphyromonas gingivalis; D018713:Prevotella intermedia; D011446:Prospective Studies
keywords: Debonding; Orthodontic treatment; Periodontal pathogen; Saliva