Evaluation of masticatory muscle activity in patients with unilateral posterior crossbite before and after rapid maxillary expansion

The relationship between unilateral posterior crossbite (UPCB) and the possible asymmetric activation of the jaw muscles in children is still under debate. This study aimed at evaluating the jaw muscle activity of children with UPCB before and after rapid maxillary expansion (RME) by means of surface electromyography and a standardized sampling protocol