Electromyographic evaluation in children having rapid maxillary expansion.
BACKGROUND
The aim of this study was to analyze the electromyographic activity of the masseter and temporalis muscles of children having rapid maxillary expansion (RME) with a bonded rapid maxillary expansion appliance.


METHODS
The sample consisted of 27 children (mean age, 8.6 years) with posterior crossbite who required RME treatment. Electromyographic activity of the masseter and temporalis muscles was analyzed before treatment and after the appliance was removed. The mean interval between the 2 analyses was 5 months. Muscular activity was electromyographically analyzed in rest position, and with maximum voluntary dental clenching and chewing. Differences in the 2 measurements were evaluated by using paired t tests.


CONCLUSIONS
Electromyographic analysis showed that activity of the masseter and temporalis muscles increased significantly after the expansion appliance was removed during rest, dental clenching, and habitual chewing.
De Rossi
Moara
M
Postgraduate student, Department of Pediatric Dentistry, Piracicaba School of Dentistry, State University of Campinas, São Paulo, Brazil.
De Rossi
Andiara
A
Hallak
Jaime Eduardo Cecílio
JE
Vitti
Mathias
M
Regalo
Simone Cecílio Hallak
SC
D002648:Child; D003818:Dentition, Mixed; D004576:Electromyography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000628:therapy; D008406:Masseter Muscle / Q000503:physiopathology*; D008409:Mastication / Q000502:physiology; D009119:Muscle Contraction / Q000502:physiology; D016382:Orthodontic Appliance Design; D018704:Orthodontic Retainers; D010155:Palatal Expansion Technique / Q000295:instrumentation; D013703:Temporal Muscle / Q000503:physiopathology*; D014716:Vertical Dimension