Stability of Maxillary Expansion and Tongue Posture

Objective: 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. Materials and Methods: 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: 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. Conclusions: A higher tongue posture can be obtained with RME in children with no reported respiratory disturbances. (Angle Orthod. 2009:79; )