The research on temporomandibular joint clicking: a methodological review

The large variance in the reported prevalence of TMJ clicking is a result of the study of nonrepresentative groups, the use of different instruments, and the lack of a definition of "abnormal" clicking. Etiologic studies must be regarded with caution because it is not clear which mechanisms trigger TMJ clicking (or how) and because TMJ research is usually quasi-experimental, which precludes definitive conclusions concerning cause and effect. The lack of objective criteria makes diagnosis difficult. It is suggested that psychological factors such as symptom perception and report play a role in the decision to seek help, in the diagnosis, and in the treatment.