Short-term sagittal changes of the upper and lower jaws in patients treated with acrylic-splint rapid palatal expander before growth peak

Rapid palatal expansion can determine an improvement of the sagittal relationship between maxilla and mandible. The purpose of this study was to evaluate the skeletal and dentoalveolar effects of the upper and lower jaws on the sagittal plane in subjects treated with acrylic-splint rapid palatal expander before growth peak. 36 patients aged 6-10 years with a cervical vertebral maturation stage of CS1 or CS2 were selected. Skeletal and dentoalveolar variables on the cephalometric traces of the lateral teleradiographs were measured before (T0) and at the end (T1) of the orthodontic treatment. The same variables were measured in a subgroup (20 subjects) of the same sample, characterized by a skeletal Class II malocclusion (ANB >= 4 degrees) at T0. Statistics used was paired samples t-test. The p-value was considered statistically significant for P