Importance of evaluating the presence of temporomandibular disorders in chronic pain patients

BACKGROUND AND OBJECTIVES: Chronic pain patients have lower pain threshold, thus having pain in other parts of the body. This study aimed at evaluating the presence of temporomandibular disorders in patients with chronic pain in different parts of the body comparing them to a pain-free control group. In addition, we tried to determine which group had more temporomandibular disorder symptoms and myofascial changes in masticatory muscles. METHODS: Sample was made up of 180 individuals divided in 2 groups, being 90 patients with chronic pain in different parts of the body: study group, and 90 pain-free patients: control group. The questionnaire proposed by the American Academy of Orofacial Pain was used to diagnose temporomandibular disorder symptoms. A directed and validated physical evaluation was performed. Analyses were done to determine the frequency of temporomandibular symptoms both in the control group and the study group, and the presence of muscular temporomandibular disorders in both groups. RESULTS: Among chronic pain patients, 70% had temporomandibular disorder symptoms and in the control group they were 55%. Patients with symptoms were physically evaluated and it was observed that 45% had masticatory muscles myofascial pain as compared to 28% in the control group. CONCLUSION: The prevalence of temporomandibular disorder symptoms and masticatory muscles pain was higher among chronic pain patients as compared to the control group and should be taken into consideration when the proposal is to evaluate and control all pains of such patients.