title: [The influence of two kinds of crown margin designs on MMP-8 and TIMP-1 levels in gingival crevicular fluid ].
abstract: OBJECTIVE
  To explore the influence of two kinds of crown margin designs on MMP-8 and TIMP-1 levels in gingival crevicular fluid(GCF).
  
  
  METHODS
  16 cases of patients who needed full crowns were divided randomly into two groups: subgingival group and gingival crest group. The GCF were taken before tooth preparation, one month, three months and six months after crown placement. The levels of MMP-8 and TIMP-1 in GCF were determined by ELISA.
  
  
  RESULTS
  The levels of MMP-8 and TIMP-1 in GCF before tooth preparation made as baseline. The level of MMP-8 at one month after crown placement in subgingival group was higher than the baseline ( P <0. 05) and contiue increasing at three months after crown placement. The level of MMP-8 at six months after crown placement in subgingival group decreased, but it was higher than the baseline(P<0.05). In gingival crest group, atfer inserting crowns, the levels of MMP-8 and TIMP-1 was no signifieantly change. In two gourps, atfer inserting crowns, the levels of MMP-8 and TIMP-1 signifieantly increased. The level of MMP-8 in subgingival group was higher than that in gingival crest group at all times and the level of TIMP-1 in subgingival group was lower than that in gingival crest group.
  
  
  CONCLUSIONS
  Gingival crest crown margin design is more fvourable to the effect of MMP-8 and TIMP-1 in maintaining the health and the regular remodeling of the periodontium.
authors.affiliation: Department of Prosthodontics, Affiliated Stomatology Hospital, Chongqing Medical University, Chongqing 400015, USA. pmy2005@sina.com
authors.forename: Ming-yong
authors.initials: MY
authors.lastname: Peng
authors.forename: Li
authors.initials: L
authors.lastname: Zhao
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhang
authors.forename: Chang-hong
authors.initials: CH
authors.lastname: Hu
mesh_terms: D000328:Adult; D003442:Crowns; D005260:Female; D005883:Gingival Crevicular Fluid / Q000737:chemistry*; D006801:Humans; D008297:Male; D020784:Matrix Metalloproteinase 8 / Q000032:analysis*; D008875:Middle Aged; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000032:analysis*
chemical_list: C560822:TIMP1 protein, human; D019715:Tissue Inhibitor of Metalloproteinase-1; C488762:MMP8 protein, human; D020784:Matrix Metalloproteinase 8