Mobilização articular em pacientes com disfunção temporomandibular: estudo controlado randomizado

Abstract

Temporomandibular disorder (TMD) is a condition that affects the masticatory muscles, and associated structures. The physiotherapy approach in TMD includes modalities, which can be applied individually or combined, such as: ultrasound, laser therapy, mobilization of temporomandibular joint (TMJ) and cervical spine and cervical manipulation. These interventions still need to be better investigated regarding their effects and with quantitative tools for evaluating the craniocervicomandibular system structures. Thus, this research aims to verify the effect of TMJ and hyoid bone mobilization on the pain threshold and electromyographic activity of masticatory and cervical muscles, in women with severe TMD. Furthermore, it proposed to evaluate the response of this technique on cervical dysfunction. The participants were 26 women, mean age of 27.92 (± 6.06) years, with diagnosis of TMD, assessed by Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and classified as severe, according to the Temporomandibular Index score (TMI > 0.5). All participants were divided randomly into two groups: control group (CG, n = 13) and treatment group (TG, n = 13). They were evaluated, as the cervical dysfunction, through the Craniocervical Dysfunction Index (CCDI); pain threshold, by algometry of masticatory and cervical muscles and surface electromyography of these muscles, at rest and maximum intercuspal (MI) situations. The evaluations were performed at the beginning (A1) and, after five weeks (A2) in both groups. The participants of the TG were submitted to 10 physiotherapy sessions, consisted by TMJ and hyoid bone mobilization techniques. The participants of CG waited to be treated after this period. In the evaluation of the diagnostic subgroups of TMD, there was a reduction of mixed dysfunction from 92.3% to 15.4%, respectively, at A1 and A2, in the TG. Furthermore, TMD diagnosis present in all patients at A1, was suppressed in 69,25% of TG patients at A2. Houve um aumento de 27,40% no limiar de dor no músculo temporal anterior e 8,57% de diminuição na região inferior do masseter no GT, na comparação entre A1 e A2.In both groups, there was an increase in the pain threshold in the middle region of the masseter ( 10 and 7,98 % in GC and GT , respectively) . Furthermore, increased pain threshold was observed in subocciptal muscles, 1,42% and 6,23 % in the CG and TG , respectively and in 30,18% in scalene in GT. The electrical activity of the sternocleidomastoid , during MI, increased 6,97% in the control group and 6,32% in GT. Masticatory muscles showed no difference between groups and between assessments (A1 and A2 ) in both groups. These findings show that the joint mobilization was effective in suppressing TMD diagnosis, improving cervical dysfunction and painful sensitivity of anterior temporal muscle. The technique does not interfere in the muscle activity, which showed little altered in the study participants, although they presented severe TMD.