title: Cytokine levels in crevicular fluid are less responsive to orthodontic force in adults than in juveniles.
abstract: OBJECTIVE
  Bone remodelling during orthodontic tooth movement is related to the expression of mediators in gingival crevicular fluid (GCF). No information is available concerning the effect of age on the levels of these mediators in GCF. The purpose of this study was to quantify three mediators (prostaglandin E2, interleukin-6 and granulocyte-Macrophage Colony-Stimulating Factor) in GCF during orthodontic tooth movement in juveniles and adults.
  
  
  METHODS
  A total of 43 juvenile patients (mean age 11 +/- 0.7 year), and 41 adult patients (mean age 24 +/- 1.6 year) took part in the study. One of the lateral incisors of each patient was tipped labially, the other served as control. GCF samples were taken before force activation (t0) and 24 h later (t24). Mediator levels were determined by radioimmunoassay (RIA).
  
  
  RESULTS
  PGE2 concentrations were significantly elevated at t24 in juveniles and adults, while concentrations of IL-6 and GM-CSF were significantly elevated only in juveniles. Total amounts of all three mediators in GCF significantly increased at t24 in both groups.
  
  
  CONCLUSIONS
  In early tooth movement, mediator levels in juveniles are more responsive than levels in adults, which agrees with the finding that the initial tooth movement in juveniles is faster than in adults and starts without delay.
authors.affiliation: Department of Orthodontics & Oral Biology, University Medical Centre St Radboud, Nijmegen, the Netherlands. R.Yijin@dent.kun.nl
authors.forename: Yijin
authors.initials: Y
authors.lastname: Ren
authors.forename: Jaap C
authors.initials: JC
authors.lastname: Maltha
authors.forename: Martin A
authors.initials: MA
authors.lastname: Van't Hof
authors.forename: Johannes W
authors.initials: JW
authors.lastname: Von Den Hoff
authors.forename: Anne Marie
authors.initials: AM
authors.lastname: Kuijpers-Jagtman
authors.forename: Ding
authors.initials: D
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000367:Age Factors; D016723:Bone Remodeling / Q000502:physiology*; D002648:Child; D016207:Cytokines / Q000096:biosynthesis*; D003799:Dental Stress Analysis; D015232:Dinoprostone / Q000096:biosynthesis; D005883:Gingival Crevicular Fluid / Q000378:metabolism*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000096:biosynthesis; D006801:Humans; D007180:Incisor; D018836:Inflammation Mediators / Q000378:metabolism*; D015850:Interleukin-6 / Q000096:biosynthesis; D008297:Male; D008437:Maxilla; D016910:Orthodontic Brackets; D014087:Tooth Movement Techniques
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators; D015850:Interleukin-6; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D015232:Dinoprostone