title: Immunohistochemical expression of matrix metalloprotease-2 and matrix metalloprotease-9 in the disks of patients with temporomandibular joint dysfunction.
abstract: OBJECTIVE
  Matrix metalloproteases (MMPs) are tissue-remodeling enzymes that function during the remodeling process, such as in immune-inflammatory diseases. Metalloprotease-2 (MMP-2) and metalloprotease-9 (MMP-9) are gelatinases that degrade several types of extracellular matrix collagen. It is hypothesized that in temporomandibular joint (TMJ) dysfunction, MMP-2 and MMP-9 expression levels may be elevated. Therefore, the objective of this study is to determine the association of MMP-2 and MMP-9 expression with temporomandibular joint dysfunction using an immunohistochemical approach to evaluate the joint disk.
  
  
  METHODS
  A total of 45 human temporomandibular joint samples were collected, with 36 samples in the test group (patients with anterior disk displacement with reduction (n = 29) and without reduction (n = 7)) and nine samples in the control group. The immunostaining of the TMJ disks was statistically compared between the groups (P < 0.05).
  
  
  RESULTS
  There was a statistically significant difference for the area of MMP-2 immunostaining between the control group and the displacement disks with reduction group (ADDwR) (P = 0.048) and between the groups with disk displacement and without reduction (ADDwoR) (P = 0.029). The expression of MMP-2 was significantly elevated in the ADDwoR group.
  
  
  CONCLUSIONS
  No statistically significant difference was found between the variable area of MMP-9 expression in the disk with and without disk displacement, as determined by immunohistochemical analysis. However, there was an elevation of MMP-2 expression in the disks of patients with displacement and without reduction (more severe alteration).
authors: Department of Oral Sciences, Oral Surgery, Marquette University, School of Dentistry, Milwaukee, WI, USA.
authors: Luis Eduardo
authors: LE
authors: Almeida
authors: Karina
authors: K
authors: Caporal
authors: Viviane
authors: V
authors: Ambros
authors: Marina
authors: M
authors: Azevedo
authors: Lucia
authors: L
authors: Noronha
authors: Rosy
authors: R
authors: Leonardi
authors: Paula C
authors: PC
authors: Trevilatto
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D004204:Joint Dislocations / Q000201:enzymology / Q000473:pathology; D008297:Male; D008335:Mandibular Condyle / Q000201:enzymology / Q000473:pathology; D020778:Matrix Metalloproteinase 2 / Q000032:analysis*; D020780:Matrix Metalloproteinase 9 / Q000032:analysis*; D008875:Middle Aged; D019224:Temporomandibular Joint Disc / Q000201:enzymology* / Q000473:pathology; D013705:Temporomandibular Joint Disorders / Q000201:enzymology* / Q000473:pathology; D055815:Young Adult
chemical_list: C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2; C579270:MMP9 protein, human; D020780:Matrix Metalloproteinase 9
keywords: matrix metalloproteinases; temporomandibular joint disorders