Anterior open bite treated with palatine crib: a case report with cephalometric, speech and electromyography analyses

Abstract

Objective: This case report describes an interceptive treatment of anterior open bite (AOB) with fixed palatine grid using clinical, cephalometric, electromyographic and speech analysis data. Case report: An 8-year-old girl, Angle Class I malocclusion presenting AOB. The complete orthodontic documentation was obtained and the perioral muscles were evaluated using the electromyography during blowing, sucking and smiling activities, before and after treatment. Speech acoustic evaluation was performed through the frequencies of the formants to assess the position of the tongue. Results: The AOB was corrected in six months with reduction of vertical transpass, decrease of cephalometric Angles 1: NA and 1: NB and increase of interincisal angle. During the smile movement, it was possible to observe the decrease of the muscular activity of the superior orbicularis muscle and the increase of the muscular activity of the inferior orbicularis. In the blow movement, there was a tendency to decrease muscle activity. Opposite directions were observed at the time of installation of the grid in the frequencies of the formants. When the grid was removed, the tongue was lowered and posteriorized in relation to the installation time. When compared the final and initial moments, it was noted a predominance of tongue lower position, besides posteriorization in some vowels and anteriorization in others. Conclusion: After the use of the fixed palatine crib as an interceptive treatment for AOB, the bite was closed and it was possible to observe an harmony in the patient profile and improvement in periorbital musculature and tongue positioning.