Evaluation of cephalometric changes in Class II malocclusion following expansion vs. extraction orthodontic treatment: a comparative retrospective study

This study evaluated cephalometric changes in Class II malocclusion patients treated with expansion versus extraction in a Saudi Arabian sample. Data from 90 orthodontic patients meeting strict eligibility criteria were collected from multiple private practices in Saudi Arabia. The sample was divided according to treatment modality: Group 1 consisted of patients treated with four premolar extractions (<i>n</i> = 45), and Group 2 included patients treated with maxillary expansion using a banded rapid palatal expander (RPE) supported by mini-screws (<i>n</i> = 45). Nasolabial angle (NLA) for extraction cases presented a statistically significant difference in post-treatment radiographs (mean difference: -3.07 ± 8.92, <i>P</i> = 0.030) and significant changes in all dental variables (e.g., upper incisor position to A-Pog [UI-APog] pre-treatment mean difference: 4.49 ± 3.89; <i>P</i> < 0.001). In pre-treatment radiographs, only the position of the upper incisor to A-Pog showed a considerable difference (11.27 ± 4.19 vs. 8.83 ± 3.00, <i>P</i> = 0.017). Cases treated with RPE reported significant changes in the lower lip thickness (mean difference: -1.02 ± 2.20, <i>P</i> = 0.028). Cases treated with extraction had a greater influence on the dental component than on the soft tissue. In contrast, expansion cases showed a slight impact dentally but a greater effect on soft tissue parameters. However, neither treatment modality resulted in significant skeletal changes.