Arthrographic and clinical characteristics patients with disk displacement who progressed to closed lock during a 6-month period.

The course of 61 patients with a clinical and arthrographic diagnosis of disk displacement with reduction was followed for 6 months. Progression to closed lock (disk displacement without reduction) occurred in 12 patients (20%). A retrospective analysis of the findings from the clinical and arthrographic examination at the first consultation revealed that the intensity of temporomandibular joint pain during chewing and the degree of disturbed joint function were more pronounced and the frequency of temporary locking was higher in the patients who progressed to closed lock compared with those who did not progress to closed lock. A deep anterior recess of the lower joint compartment was found in ten (83%) of the twelve joints that progressed to closed lock. This type of a deep anterior recess was seen in only five (11%) of the forty-nine patients who did not progress to closed lock. Progression seems to be more likely in patients with pronounced joint pain and disturbed joint function, temporary locking, and a deep anterior recess of the lower joint compartment. These clinical and arthrographic features may be used during evaluation of patients with disk displacement with reduction.