A CBCT Evaluation Of Nasofacial Structures After Maxillary Skeletal Expansion

The aim of study was to evaluate three-dimensional (3D) changes in related nasofacial structures after maxillary skeletal expansion (MSE). Retrospective study evaluated 21 patients aged 11.5–20 years diagnosed with maxillary transverse deficiency (MTD) and treated with MSE. Cone-beam computed tomography (CBCT) images were taken at pre-expansion (T1) and 6-months after MSE (T2) and were reoriented. 3D coordinates were constructed using nasion (N) as the reference point. The maxillary basal bone width, piriform aperture width (PAW), nasal base width, inter-molars width, molar inclination, molar palatal cusp height (U6H), suture expansion width, suturae nasofrontalis width, inter lateral pterygoid palate width were measured using Dolphin Imaging. A paired-sample t-test and an independent sample t-test were performed to investigate and compare the 3D changes of the nasofacial structures after MSE, depending on the direction and amount of midpalatal expansion (MPE). Nasal septal length increased significantly. The absolute nasal base width increased at T2–T1 (p < 0.05). The midface moved forward and downward, and pogonion (Pog) and menton (Me) moved downward and backward. Variable positive nasofacial changes after MSE in both the short and long term. Therefore, MSE can be used to improve or camouflage facial deformities.