Functional evaluation in young patients undergoing orthopedical interceptive treatment

BACKGROUND: The aim of this study was to examining the activity of jaw muscles through electromyograph and electrognatograph in children with unilateral posterior cross-bite and functional lateral shift before and after rapid palatal expansion, and to find out a relationship between the results. METHODS: The sample included 71 children (35 females and 36 males; range: 6-10 years) with unilateral posterior cross-bite and functional mandibular lateral shift in mixed dentition. Superficial Electromiographic activity coming from the muscles areas (anterior temporalis and masseters) and electrognatographic exam were obtained before (T0) and after rapid palatal expansion (T1) and after a follow-up period of 6 months (T2). RESULTS: A significant increase was found in the value of activity index between T0, T1 and T2 in all the analyzed muscles both in rest position and during the exercises of the different acquisitions, at the end of the active phase of the rapid palatal expansion. CONCLUSIONS: The evaluation of EMG activity after rapid palatal expansion is important to confirm the adaptation of the neuromuscular system to the new occlusal condition. In this study, the muscular activity was increased after therapy producing important changes in muscular tone.