Chronic myofascial pain, disk displacement with reduction and psychosocial factors in Finnish non-patients.

This study aimed to determine chronic groups of myofascial pain and chronic disk displacement with reduction over a 1-year period, and to study the relationship between psychological status and these chronic subgroups of temporomandibular disorders (TMD) in non-patients. A total of 211 subjects (males 47%, mean age 46 years; standard deviation 6) attended examinations in 1999 and 2000 performed according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Chronic myofascial pain was found in 7% and chronic disk displacement with reduction in 11% of subjects; new diagnoses were made in only 4% and 1% of the subjects, respectively. An increase in the level of somatization by 1 step increased the probability of having chronic myofascial pain by over 3 times (P = 0.006). Myofascial pain and disk displacement with reduction seem to be relatively common and fluctuating in nature in non-patients. As somatization associated significantly with myofascial pain, this should be borne in mind in the management of TMD. The results strengthen the rationale of the biopsychosocial orientation in health care.