Personality traits are potentially associated with the presence of chronic temporomandibular joint pain in patients without effusion as determined by T-2 weighted magnetic resonance

The study aimed at investigating personality traits in chronic temporomandibular joints (TMJ) pain patients with and without joint effusion. METHODS: Two groups of chronic TMJ pain patients were recruited. The TMJ pain control group was composed of patients showing magnetic resonance imaging (MRI) signs of TMJ effusion, while the TMJ pain test group included patients with chronic TMJ pain seemingly not justified, due to the absence of MRI-detected disorders. A third set of pain free individuals was selected as a comparison group. All patients completed a personality assessment with the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) instrument, and the between-group differences were assessed for significance by performing an analysis of variance test. RESULTS: Patients of the TMJ pain test group had higher scores than subjects belonging to the TMJ pain and pain-free control groups in almost all of the MMPI-2 clinical scales. A significant difference was shown for the scales related to concerns about physical health (Scale 1-Hs; F = 7.74; p = .001) and physical symptoms (Scale 3-Hy; F = 8.43; p = .001). CONCLUSIONS: Chronic TMJ pain patients without MRI-detected TMJ effusion have a different personality profile than patients with TMJ effusion and pain-free individuals, regarding high levels of concerns about physical health and physical symptoms. CLINICAL IMPLICATIONS: This study has important clinical implications for temporomandibular disorders practitioners, providing suggestions that symptoms in the TMJ area are not only related to a physical disorder. The possible existence of a psychologically modulated condition in patients who refer pain in the TMJ area without signs of effusion should be carefully taken into consideration.