OBJECTIVETo investigate the clinical natural course of temporomandibular joint (TMJ) intermittent closed lock (ICL) through 24 months follow-up.

METHODSSixty-eight patients with ICL were included, and 54 patients finished 24 months follow-up. The disease duration, frequency of joint lock and joint pain were recorded at the patient's first visit. Telephone interviews were taken for every month, and the frequency of joint lock and joint pain were recorded. According to the development of ICL, the patients were divided into 3 groups: symptom-worsened group, symptom-disappeared group, symptom-persisted group.

RESULTSThere were 16 patients (30%) whose symptoms worsened into closed lock (disk displacement without reduction), 32 patients (59%) whose symptoms persisted during the 24 months follow-up, and 6 patients' (11%) symptoms disappeared. In symptom-persisted group, the frequency of joint lock decreased in 11/32 (34%), increased in 4/32 (13%), did not change in 17/32 (53%). There was no significant difference in gender, age, frequency of joint lock and joint pain recorded at the first visit among these 3 groups (P > 0.05). The disease duration in the symptom-disappeared group was much shorter than the other 2 groups (P < 0.05).

CONCLUSIONSICL of TMJ was more likely to get worse into closed lock. There seemed no significant relation between the sequelaes of ICL and patients' gender, age, disease duration, frequency of joint lock and joint pain, and larger sample studies were necessary.