title: Expression of IL-1beta, MMP-9 and TIMP-1 on the pressure side of gingiva under orthodontic loading.
abstract: OBJECTIVE
  To test the hypothesis that orthodontic pressure does not induce gene transcription of IL-1beta, MMP-9, and TIMP-1 in pressure gingival soft tissue.
  
  
  METHODS
  A total of 14 male Wistar rats were used with three rats as no appliance controls and another three as the sham appliance group. On the 7th and the 14th day after orthodontic loading on the maxillary left molar, four rats were sacrificed, respectively. Maxillary right first molars served as the contralateral control side. A real-time RT-PCR for the excised gingiva was performed to measure the mRNA of IL-1beta, MMP-9, and TIMP-1.
  
  
  RESULTS
  Compared with the contralateral side, IL-1beta mRNA from the pressure side significantly increased on the 7th day, then decreased on the 14th day (P < .05). MMP-9 and TIMP-1 mRNA showed a significant constant increase on both the 7th and the 14th day (P < .05).
  
  
  CONCLUSIONS
  The hypothesis is rejected. Orthodontic loading led to increases in IL-1beta, MMP-9, and TIMP-1 mRNA in pressure side gingiva in rats.
authors.affiliation: Department of Orthodontics, College of Dentistry, Yonsei University, Seoul, South Korea.
authors.forename: Tae-Yeon
authors.initials: TY
authors.lastname: Lee
authors.forename: Kee-Joon
authors.initials: KJ
authors.lastname: Lee
authors.forename: Hyoung-Seon
authors.initials: HS
authors.lastname: Baik
mesh_terms: D000818:Animals; D003799:Dental Stress Analysis; D015870:Gene Expression; D005881:Gingiva / Q000378:metabolism*; D053583:Interleukin-1beta / Q000096:biosynthesis*; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis*; D009967:Orthodontic Appliances; D011312:Pressure; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000096:biosynthesis*; D014087:Tooth Movement Techniques
chemical_list: D053583:Interleukin-1beta; D012333:RNA, Messenger; D019715:Tissue Inhibitor of Metalloproteinase-1; D020780:Matrix Metalloproteinase 9