Abstract
Objective: Since masticatory muscle pain is caused by the involvement of multiple factors, there are large individual differences in the duration of illness. Therefore, the purpose of this study was to investigate the psychosocial factors by screening tools whether would influence the duration of illness.
Method: Screening questionnaire for age, gender, and psychosocial factors at the time of diagnosis （Patient Health Questionnaire-9, Patient Health Questionnaire-15 and Generalized Anxiety Disorder-7） from those who were diagnosed with masticatory myalgia and obtained their consent） Score, disease duration （time from onset of subjective symptoms to diagnosis）, and subtype of masticatory muscle pain （local myalgia or myofascial pain）. From the obtained data, the median illness period was calculated. Then, logistic regression analysis was performed with the disease duration （binary variables below and above the median） as the dependent variables and the age, gender, and psychosocial factor scores and the subtype of masticatory muscle pain as the independent variables. We identified the factors that affect the disease duration.
Results: The number of subjects was 68. Patient Health Questionnaire-15 was significant, but other items were not. The odds ratio for Patient Health Questionnaire-15 was 1.25 （95％ Cl 1.09-1.43, p＝0.002）.
Conclusion: The most relevant factor for the duration of illness in patients with masticatory muscles was the PHQ-15 （physical symptom） score.
