Effects on the Tongue Positions after Maxillary Protraction Treatment Using Rapid Maxillary Expander or Miniplates

Abstract

Maxillary protraction treatment has been widely used for growing patients with Class III malocclusion. This report shows two patients who received maxillary protraction treatment using the facemask and the rapid maxillary expander (RME/FM) or the miniplates (Miniplate/FM) as an intraoral anchorage. The first patient was a 7.8-year-old female who received RME/ FM treatment for Class III malocclusion. Her occlusion and maxillomandibular relationship were improved and the tongue was positioned more inferiorly after treatment. The second patient was a 8.1-year-old female who received Miniplate/FM treatment. Her Class III malocclusion was corrected, and the tongue was positioned more superiorly after treatment. A preliminary study on the tongue position after maxillary protraction treatment was performed with a RME/FM group (n=10, 8.7 ± 0.8 years old) and Miniplate/FM group (n=10, 9.8 ± 1.6 years old). Pretreatment and posttreatment cephalometric radiographs were analyzed, and the tongue position was compared. The tongue position was significantly changed more posteriorly in the RME/FM group and more superiorly in the Miniplate/FM group. The tongue position might change after a maxillary protraction treatment, and it may differ depending on the type of the intraoral appliances for maxillary protraction.