Temporomandibular joint disorders (TMD) affect the joint, the masticatory muscles, or are expressed as a clinical combination of these two factors. The aims of this study were to: (i) identify the clinical and psychosocial factors that aid in the diagnosis and classification of acute and chronic TMD, (ii) determine specific initiating and perpetuating factors which may act as a guide to differentiate between acute and chronic TMD, (iii) identify factors which might predispose to conversion from acute to chronic TMD. Twenty-two patients were examined in the pain clinics at the Eastman Dental Institute. The assessment technique incorporated questionnaires, clinical history and examination including dental panoramic tomography. The results of this pilot study show a significant correlation between mood and enjoyment of life in both groups, mood and relationships in the chronic group, average pain and sleep in the chronic group, average pain and eating chewing in the chronic group, and phobia for physical disease with trust in clinicians in the chronic group. The bio-psychosocial model of pain is an important appraisal tool. The newly designed TMD Pain Assessment is described with good results.