A four-year follow-up, by means of a questionnaire, of patients with functional disturbances of the masticatory system.

From a group of consecutive patients referred for diagnosis and treatment of functional disturbances of the masticatory system, two groups, a young group (16-30 years, 113 subjects) and an older group (55-80 years, sixty-three subjects) were selected for a follow-up study. A self-administered questionnaire was mailed to them 4 years after the start of treatment. They had answered a similar questionnaire at the first visit. Of the selected patients, 148 (84%) participated. If explainable losses are excluded, the response rate was 89%. Most of the pain and dysfunction symptoms had diminished significantly in frequency while 'peripheral' symptoms such as tinnitus, vertigo, tongue pain and swallowing difficulties had the same prevalence on both occasions. Two-thirds of the patients reported a positive effect of treatment, without any significant difference between the younger and the older group. The remaining symptoms differed, however. The older group reported pain in the face and jaws, vertigo, tinnitus, tongue pain and TMJ crepitation more often than the younger group, while the opposite was found for TMJ clicking and tooth grinding. Only one variable from the original questionnaire (duration of initial symptoms), with none from the first clinical examination, was significantly correlated to the retrospective assessment of treatment outcome. This shows that it is difficult to predict the long-term outcome of treatment from data collected at the first examination of a patient with TMJ pain and dysfunction, but that a long duration of symptoms may have a negative influence on the prognosis.