RATIONALE OF THE OBSERVATION STUDY: This study aims to observe which patients with temporomandibular disorder improve more following a physiotherapy program of four sessions. Knowing the characteristics of patients who have the most significant improvements could help clinician advise or advise against physiotherapy for the treatment of temporomandibular disorders. STUDY PROCEDURES The study will be conducted at the Istituto Stomatologico Italiano. Patients diagnosed with Temporomandibular Disorder will be recruited in the gnathological and neuromuscular gnathological departments. The physiotherapists of the Craniomandibular Physiotherapy Service will perform physiotherapy therapy, which consists of four physiotherapy sessions \[lasting 30 minutes, about once a week\] over a month. Before starting the treatment, participants will be asked to answer some questions concerning their state of health (e.g. pain intensity) with particular reference to Temporomandibular Disorder (e.g. location and duration of pain). The intensity of pain and the level of function will then be monitored at baseline, after 4 weeks and after 8 weeks from baseline. EXPECTED BENEFITS FROM THE STUDY AND EXPECTED BENEFITS FOR THE PATIENT The benefits are the discovery of new knowledge in the field of therapeutic choice for patients with temporomandibular disorder.