Stability of Maxillary Expansion and Tongue Posture

Abstract

To evaluate the adaptive changes and the stability in tongue posture following rapid maxillary expansion (RME) in patients without any signs or symptoms of respiratory disturbances. Growing subjects with maxillary constrictions and bilateral buccal crossbites were included in the treatment group (n = 20). A control group (n = 20) comprised subjects with normal dentoskeletal features. RME appliances were used in the treatment group, with an average active expansion of 15 +/- 2 days. Cephalometric radiographs were traced and digitized to evaluate static tongue posture before RME and 6.75 +/- 0.48 months after RME. Follow-up radiographic evaluations of 17 expansion cases were also performed after an average of 29.25 +/- 1.85 months. Independent and paired t-tests were conducted to evaluate changes in tongue posture within and between groups. Results revealed significant reductions of tongue-to-palate (P < .05) as well as hyoid bone-to-mandibular plane (P < .01) distances following RME. The new tongue posture was found to be stable during the follow-up period. A higher tongue posture can be obtained with RME in children with no reported respiratory disturbances.