Personality traits and behavior can have a significant influence on the treatment success in patients with temporomandibular disorders (TMD). Chronic pain is an essential criterion in the evaluation of psychological assessment, according to the recommendations for the standardized diagnostic criteria of TMD. The aim of the study was to evaluate whether persistent pain can be applied as a diagnostic decision criterion for the evaluation of psychosocial assessment like depression, unspecific pain (somatization) and pain related disability, and to find out the correlation strength between pain, depression and somatization. In 402 patients with a TMD diagnosis according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), pain intensity and disability were assessed using the Graded Chronic Pain Scale (GCPS), depression was assesssed using the German version of the Center for Epidemiological Studies Depression Scale ( ADS-L) and somatization (unspecific somatic complaints) was assessed using a complaints list (Beschwerdenliste, B-L). TMD patients with chronic pain have psychosocial impairments more often than patients with acute pain or without any pain. Therefore, psychosocial assessment should be applied regularly in the treatment of TMD patients with persistent or chronic pain. Keywords: persistent pain, temporomandibular disorders, depression, pain intensity, somatization