Disorders of masticatory muscles before and after posterior cross bite treatment: EMG analysis - De-Rossi, M.; Gavião, Maria Beatriz Duarte; Stuani, Maria Bernadete Sasso; Vitti, Mathias; De-Rossi, A.; Hallak, Jaime Eduardo Cecílio; Semprini, Marisa; Regalo, Simone Cecílio Hallak (Congress of The International Society of Electrophysiology and Kinesiology, 2006)