title: [Measurement and analysis of the intra-articular pressure in temporomandibular joint with sudden-onset, severe closed lock].
abstract: OBJECTIVE
  The study aims to find out the fluctuating curve of the intra-articular pressure in temporomandibular joint with sudden-onset, persistent, severe closed lock and discuss the mechanism of its formation. We also investigate the effects of the arthrocentesis.
  
  
  METHODS
  20 affected sides in 16 patients were collected. A No. 8 syringe needle was used to pierce into the upper compartment of TMJ. The pre-arthrocentesis intra-articular pressure was measured by the pressure transducer via the flexural rigid tubing at open and close bite. The curve and mean value were documented during the operation.
  
  
  RESULTS
  The patients with sudden-onset, persistent, severe closed lock had significantly low negative intra-articular pressure in their affected temporomandible joints. The average pressures was (-9.947 +/- 8.854) kPa at open bite and (-6.475 +/- 4.147) kPa at close bite.
  
  
  CONCLUSIONS
  The TMJs with sudden-onset, persistene, severe closed lock has particular characters on etiology and clinical behavior. Arthrocentesis is one of the effective treatments to the diseases.
authors.affiliation: Dept. of Orthodontics, West China College of Stomatology, Sichuan University, Chengdu 610041, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Xu
authors.forename: Zhi-guang
authors.initials: ZG
authors.lastname: Zhang
authors.forename: You-hua
authors.initials: YH
authors.lastname: Zheng
mesh_terms: D000328:Adult; D003766:Dental Occlusion; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019152:Paracentesis; D016059:Range of Motion, Articular; D013704:Temporomandibular Joint; D013705:Temporomandibular Joint Disorders; D016896:Treatment Outcome