Stability of transversal correction with hybrid maxillary expansion appliance in bone and tegumental piriformis opening in relation to bone age and maturation of the midpalatal suture

To evaluate the stability of the transverse correction with a hybrid maxillary expansion appliance in the bone and tegumental piriformis opening in relation to bone age and maturation of the midpalatal suture (MPS). 15 patients with a mean initial age of 14.9 years (SD=1.50), 7 (46.7%) were female and 8 (53.3%) were male, treated with a hybrid maxillary expander. Cone beam computed tomographic (CBCT) images were collected in three phases: T1 (orthodontic records), T2 (21.33 days (SD=10.68) after the end of expansion screw activation) and T3 after 9.13 months (DP=2.41) after the expansion screw was activated. In CBCT, measurements were performed in the nasal cavity considering the tegumental piriform opening (sagittal-axial sections) and bone (sagittal-axial-coronal sections) and the stage of MPS maturation (sagittal-axial sections). Repeated measures ANOVA was used for continuous variables and Friedman's ANOVA for the ordinal variable followed by Bonferroni's tests for