ELECTROMYOGRAPHIC EVALUATION OF THE EFFICACY OF MYOFUNCTIONAL THERAPY IN PATIENTS WITH ATYPICAL SWALLOWING

ABSTRACT Objectives: Swallowing is a complex physiologic function developing mostly in the first years of life. After 6 years old, if a complete maturation is not achieved, swallowing persists as “atypical swallowing” (AS). The therapy provided to re-educate this dysfunction is based on the myofunctional treatment (MFT). The aim of this study was to detect functional (electromyographical) and clinical (orofacial muscular evaluation with score (OMEs) protocol) effects of MFT in a group of patients with AS so to highlight any differences in the muscular activation pattern and muscular orofacial behavior. Materials and Methods: 20 adolescents and young adults (4 males and 16 females, mean age 17.85 years, SD 4.80) with AS were selected for this study. Standardized surface electromyographic (ssEMG) analysis was performed by the same operator to detect the activity of masseter (MM), temporalis (TA) and submental (SM) muscles before (T1) and after (T2) the logopedic treatment. The MFT was performed by the same speech therapist according to the Garliner method for a period of 10 weeks. The speech therapist completed the OMEs protocol at T1 and T2. A Student-t test for paired data was carried out to detect differences between T1 and T2 for both ssEMG and OMEs data. Then, a 1-way ANOVA variance test was performed to detect any differences between the different couples of muscles at T1 and T2. In addition, ssEMG data at T1 and T2 were compared with ssEMG obtained in a control (C) group of 18 adolescents and young adult patients (8 males and 10 females, mean age 17.28 years, SD 2.56) with bimolar class 1 and without AS. Results: From the starting group of 20 patients, 15 patients completed the MFT (4 males and 11 females, mean age 17.72 years, SD 5.21). At T2, AS patients showed a significantly shorter duration of activation for each couple of muscles and for the whole duration act of swallowing (p<.0001) as well as higher intensity of the SM activity (p<.01) than at T1. Within the AS group, at T1 the masticatory muscles (MM and TA) showed lower duration of activation (p<.05) and lower intensity of the spike (p<.0001) than SM. At T2, masticatory muscles also showed lower values for the activation index (IMPACT) (p<.0001) and for the spike position (p<.01) than SM. At T2. The OMEs protocol showed a significant increase for the total evaluation (p<.01) and specifically for appearance and posture (p<.01) and functions (p<.0001). If compared to C group, the AS group at T1 showed significantly longer duration of activation for each couple of muscles and for the whole duration act of swallowing (p<.0001) as well as lower intensity of the SM activity (p<.05) than controls. At T2 all the ssEMG data detected in AS patients showed a general improvement and moved toward the control values. The differences between AS and C groups about the duration of activation of each couple of muscles and the whole duration act of swallowing were lower at T2 than at T1 even if still significantly different from C ones (p<.0001). Conclusion: MFT confirms itself as an effective method in the treatment of AS dysfunction permitting a shortening of the muscular activation pattern, an increase in SM activity and a general improvement in the orofacial muscular behavior making them closer to the data obtained in controls. ssEMG and OMEs protocol represent valid and useful methods in the analysis of the swallowing function and in establishing the effects of the MFT.