title: Differences in the gingival crevicular fluid composition between adults and adolescents undergoing orthodontic treatment.
abstract: OBJECTIVE
  To investigate differences in the gingival crevicular fluid (GCF) composition between adolescent and adult patients undergoing orthodontic treatment with fixed appliances.
  
  
  METHODS
  Ten adolescents (14.4 ± 1.43) and 10 adults (28.5 ± 7.83) with Class I malocclusions and minor upper incisor crowding were allocated to two different age groups. Brackets were bonded only in the upper arch over the 20-week period of the experiment. Samples of GCF were collected from the labial sides of the upper incisors (experimental sites) and lower incisors (control sites) of each subject at five time points. Aliquots from diluted GCF were screened for the presence of receptor activator of nuclear factor kappa B ligand (RANKL), osteoprotegerin (OPG), interleukin-1 (IL-1), interleukin-1 receptor antagonist (IL-1RA), and metalloproteinase-9 (MMP-9) using a microarray technique. The values were statistically analyzed.
  
  
  RESULTS
  In adults, the ratio of IL-1 to IL-1RA decreased significantly (P  =  .033) in experimental sites 3 weeks after appliance placement and first archwire activation. In adolescents, the ratio of RANKL to OPG peaked 6 weeks after the insertion of the first rectangular archwire. This ratio peak found in adolescents was a consequence of a decrease in the mean concentration of OPG. No significant changes over time were observed in the concentration of MMP-9.
  
  
  CONCLUSIONS
  This study demonstrates age trends in the GCF levels of IL-1, IL-1RA, RANKL, and OPG that may be used to track differences in tissue response between adults and adolescents undergoing orthodontic treatment.
authors.affiliation: a  Assistant Professor, Department of Orthodontics, College of Dentistry, University of Florida, Gainesville.
authors.forename: Wellington J
authors.initials: WJ
authors.lastname: Rody
authors.forename: Manjula
authors.initials: M
authors.lastname: Wijegunasinghe
authors.forename: William A
authors.initials: WA
authors.lastname: Wiltshire
authors.forename: Brenden
authors.initials: B
authors.lastname: Dufault
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D015415:Biomarkers / Q000032:analysis; D005260:Female; D005500:Follow-Up Studies; D005883:Gingival Crevicular Fluid / Q000737:chemistry*; D006801:Humans; D007180:Incisor; D053590:Interleukin 1 Receptor Antagonist Protein / Q000032:analysis; D007375:Interleukin-1 / Q000032:analysis; D008297:Male; D008311:Malocclusion, Angle Class I / Q000628:therapy*; D008334:Mandible; D020780:Matrix Metalloproteinase 9 / Q000032:analysis; D008437:Maxilla; D016910:Orthodontic Brackets; D009969:Orthodontic Wires; D009971:Orthodontics, Corrective / Q000295:instrumentation; D053244:Osteoprotegerin / Q000032:analysis; D053245:RANK Ligand / Q000032:analysis; D055815:Young Adult
chemical_list: D015415:Biomarkers; C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; D053244:Osteoprotegerin; D053245:RANK Ligand; C506030:TNFRSF11B protein, human; C505688:TNFSF11 protein, human; C579270:MMP9 protein, human; D020780:Matrix Metalloproteinase 9