title: Prostaglandin E2 in temporomandibular joint synovial fluid and its relation to pain and inflammatory disorders.
abstract: OBJECTIVE
  The aim of this study was to investigate temporomandibular joint (TMJ) synovial fluid (SF) levels of prostaglandin E2 and its relation to general inflammatory activity and its influence on specific TMJ pain in patients with inflammatory TMJ disorders.
  
  
  METHODS
  The study comprised 24 patients (30 joints) with inflammatory TMJ disorders and 4 healthy persons (6 joints). TMJ pain at rest, tenderness to palpation of the TMJ, and TMJ pressure pain threshold, as well as pain during joint movements (PM), were assessed. PGE2 levels were analyzed in synovial fluid samples (SF-PGE2) and blood plasma (P-PGE2). The erythrocyte sedimentation rate (B-ESR) as well as the serum levels of C-reactive protein (S-CRP) and antinuclear antibodies were determined.
  
  
  RESULTS
  PGE2 was undetectable in the plasma and in the TMJ SF of the healthy persons. In the patients, PGE2 was detectable in 20 of the 30 (67%) SF samples. SF-PGE2 was significantly and positively correlated to PM in the patients. There were significant correlations between P-PGE2 and B-ESR as well as the S-CRP.
  
  
  CONCLUSIONS
  This study shows that the synovial fluid in patients with TMJ inflammatory disorders frequently has a detectable level of PGE2 that is related to TMJ allodynia. The plasma levels of PGE2 seem to be related to the general inflammatory activity in these patients.
authors.affiliation: Department of Clinical Oral Physiology, Karolinska Institutet, Huddinge, Sweden. per.alstergren@ofa.ki.se
authors.forename: P
authors.initials: P
authors.lastname: Alstergren
authors.forename: S
authors.initials: S
authors.lastname: Kopp
mesh_terms: D000328:Adult; D000368:Aged; D018771:Arthralgia / Q000209:etiology / Q000378:metabolism*; D001168:Arthritis / Q000209:etiology / Q000378:metabolism*; D015232:Dinoprostone / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D018709:Statistics, Nonparametric; D013582:Synovial Fluid / Q000737:chemistry*; D013585:Synovitis / Q000209:etiology / Q000378:metabolism*; D013704:Temporomandibular Joint / Q000737:chemistry*; D013705:Temporomandibular Joint Disorders / Q000209:etiology / Q000378:metabolism*
chemical_list: D015232:Dinoprostone