Influência da mobilização mandibular inespecífia de da massoterapia sobre a atividade eletomiográfica de músculos mastigatórios e o equilíbrio estático em indivíduos com disfunção temporomandibular: estudo clínico, aleatorizado e duplo cego

Abstract

Background: A number of studies have been using the sEMG in order to investigate the function or dysfunction of masticatory muscles and its associations with TMD signs and symptoms. Moreover, the stomatognatic system and its dysfunctions might be related to postural control, acting as a regulating or disturbing instrument. This study outcome allowed to verify if the facial massage therapy or the non-specific mandible mobilization produce any effect over the masticatory muscles and over the postural control. Materials and method: It is a randomized, blinded, clinical trial, where 312 voluntaries were recruited according to the pre-established criteria. The sample was composed by 30-TMD subjects (2 male and 28 female, mean age 23,43±6,68; mean high1,65±0,06; mean weight 66,62±11,17; mean CMI 24,10±3,3) which formed 2 groups: CG (control group-massage therapy) and NMG (non-specific mobilization group). Both groups were evaluated on the conditions (pre-treatment (PMS), post-immediate treatment (PMSI) and post treatment (PTMS), using RDC/TMD, Fonseca´s Anamnesic Index, anterior temporalis and masseter EMG and stabilommetry. This study protocol is registered on the Registo Brasileiro de Ensaios Clínicos ReBec: RBR9x8ssz. Results: The 3 moment comparison of the treated groups showed significant difference only for the variable CoP velocity. The difference effect observed on CG = 0,56 CoPML (closed eyes) and NSM = 0,42 and 0,47 for the CoPAP and CoPML, respectively, open eyes condition. These results confirm that the treatments used do not modify the postural control. Concerning EMG, significant difference was only found on the rest condition for CG between masseter and temporalis muscles (right and left) (F(3,41)=11.68; p < 0,0001). The differences between the muscles remained the same on the 3 conditions (PMS, PMSI e PTMS), indicating that the applied treatments did not modify the function of the studied muscles. Only NMG showed influency after treatment on pain (F(2,46)=3,46; p = 0,04), when compared to CG on the PTMS condition, indicating that joit mobilization was more effective for the treatment of pain on these subjects. Discussion: There is no an agreement on the literature related to the influence of the stomatognatic system on the postural control, however, there are no registries of CoP behavior investigation after the techniques we used. Concerning the EMG activity of the studied muscles, the studies are also controversy. Our results disagree to the literature regarding the variable pain. Nevertheless the measure technique used for this parameter was not the same as the one presented by other studies. The results of the present study showed that the applied techniques did not influence the studied variables (anterior temporalis and masseter EMG activity, CoP measurements, TMD signs and symptoms).