Factors related to the incidence of symptoms and signs of temporomandibular joint disorders in persons staying at institutions for the elderly.

To investigate the relation between temporomandibular (TM) joint disorders and various changes associated with aging, 1092 elderly persons were examined with respect to signs and symptoms of TM disorders, age, sex, oral condition, constitution, and age-related factors, such as activities of daily living. The study group comprised persons 65 years or older who were staying at institutions for the elderly.The data were analyzed by the logistic regression analysis, and the results were as follows:(1) The incidence of signs and symptoms of TM disorders was higher in women than in men (odds ratio: 1.92, 95% confidence interval: 1.34 to 2.75).(2) A significant positive correlation was found between the incidence of signs and symptoms of TM disorders and the need for assistance during eating (odds ratio: 1.49, 95% confidence interval: 1.19 to 1.89).(3) There was a significant negative correlation between body mass index and the incidence of signs and symptoms of TM disorders (odds ratio: 0.96, 95% confidence interval: 0.93 to 0.99).