BackgroundStress in patients with Juvenile Idiopathic Arthritis (JIA) has been found to be associated with orofacial pain, psychological distress, jaw dysfunction and loss of daily activities in a cross-sectional study. The aim of this study was to investigate the relations between stress and change of stress over time versus changes in orofacial pain, psychosocial factors and jaw function over a two-year period in patients with JIA.MethodsThis is a two-year prospective follow-up study involving 40 JIA patients. At baseline (2015) the median age was 12 years and at two-year follow up (2018) 14 years. The JIA patients were examined clinically and with questionnaires at baseline and follow-up with the diagnostic criteria for temporomandibular disorders (DC/TMD) and completed the same set of DC/TMD questionnaires regarding orofacial pain symptoms and psychosocial factors.ResultsChange in stress was associated with change in catastrophizing, psychological distress as well as limitation in general function and jaw function.ConclusionsThis study emphasizes the importance of maintaining a low stress level in patients with JIA since an increase in stress level over a two-year period seems to impair jaw function as well as psychological distress and catastrophizing.