Resposta terapêutica do ultrassom e alongamento muscular em pacientes com desordem temporomandibular: ensaio clínico

Abstract

Studies indicate that temporomandibular disorder (TMD) affects approximately 7-15 % of the adult population. In cases of recurrent and persistent pain occur decrease in the quality of life due to the psychological impairment, physical disability and functional limitation. In order to avoid the chronic phase of the disease, it is necessary to investigate therapeutic modalities that may relieve pain in these patients. This study aimed to evaluate the therapeutic response of ultrasound (US) and ultrasound associated with stretching of the masticatory muscles on the pressure pain threshold and the electrical activity of masseter and anterior temporal muscles in TMD patients . The study included 18 women with TMD diagnosed by the instrument Research Diagnostic Criteria for Temporomandibular Disorders (RDC / TMD). The pressure pain threshold, evaluated through algometry, and the electrical activity of the masticatory muscles were evaluated, by means of surface electromyography, before and immediately after the therapeutic procedures. The volunteers underwent three different interventions: ultrasound, ultrasound associated with stretching and ultrasound placebo, with a 1-week of minimum interval between them. No statistically significant differences in the values algometry before and after application of therapeutic resources were found. There was an increase in the symmetry of the electrical activity in the masseter muscle (p =0,03) after ultrasound associated with muscle stretching. It can be concluded that the EMG signal amplitude, the coefficient anteroposterior and the symmetry of the anterior temporal muscle, during maximal interscupal position, as well as the pain sensitivity levels to pressure did not modify with any of the tested interventions, immediately after its application, in women with myogenic or mixed TMD. The use of the ultrasound associated with muscle stretching produced a significant improvement on the masseter muscle symmetry with a single intervention.