title: Impact of orthodontic retainers on periodontal health status assessed by biomarkers in gingival crevicular fluid.
abstract: OBJECTIVE
  To evaluate whether biomarkers of inflammation and periodontal remodeling are differentially expressed in the gingival crevicular fluid (GCF) of patients wearing different types of orthodontic retainers.
  
  
  METHODS
  Thirty-one adult subjects (17 men and 14 women with an age range of 20 to 35 years) were allocated to three different groups. Group 1 consisted of 10 patients wearing fixed retainers, group 2 included 11 patients using lower removable retainers, and group 3 comprised 10 patients without retainers (control). Periodontal health assessment and GCF collection were carried out at two sites per subject: the lingual side of a central lower incisor and the lingual side of a lower second premolar. Aliquots from diluted GCF were screened for the presence of biomarkers using a microarray technique.
  
  
  RESULTS
  Group 1 patients exhibited a higher percentage of sites with visible plaque in the incisor region than the other groups (P = .03); no differences were noted in gingival bleeding and probing depths. The median concentrations (pg/mL) of interferon-gamma and interleukin-10 were significantly higher in the premolar sites of patients in group 2 (P = .01 and P = .04, respectively), whereas the concentration of matrix metalloproteinase-9 was significantly higher at the incisors of patients wearing fixed retainers (P = .02). A significant difference between the two sites was seen only in group 2.
  
  
  CONCLUSIONS
  The presence of different orthodontic retainers may promote specific alterations in the GCF composition. With retention periods potentially becoming longer, this finding may be of clinical significance.
authors.affiliation: Division of Orthodontics, School of Dentistry, University of Manitoba, Winnipeg, MB, Canada. rody@cc.umanitoba.ca
authors.forename: Wellington J
authors.initials: WJ
authors.lastname: Rody
authors.forename: Hengameh
authors.initials: H
authors.lastname: Akhlaghi
authors.forename: Sercan
authors.initials: S
authors.lastname: Akyalcin
authors.forename: William A
authors.initials: WA
authors.lastname: Wiltshire
authors.forename: Manjula
authors.initials: M
authors.lastname: Wijegunasinghe
authors.forename: Getulio Nogueira
authors.initials: GN
authors.lastname: Filho
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000032:analysis; D016022:Case-Control Studies; D003773:Dental Plaque / Q000209:etiology; D005260:Female; D005883:Gingival Crevicular Fluid / Q000737:chemistry*; D006801:Humans; D018836:Inflammation Mediators / Q000032:analysis*; D007371:Interferon-gamma / Q000032:analysis; D016753:Interleukin-10 / Q000032:analysis; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000032:analysis; D016382:Orthodontic Appliance Design; D018704:Orthodontic Retainers / Q000009:adverse effects; D010510:Periodontal Diseases / Q000209:etiology*; D018709:Statistics, Nonparametric; D055815:Young Adult
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D016753:Interleukin-10; D007371:Interferon-gamma; D020780:Matrix Metalloproteinase 9