Three dimensional palatal morphology and dentoalveolar differences after extraction and non extraction treatment in class II malocclusion

Digital technologies have transformed orthodontics by enabling precise three-dimensional (3D) assessment of treatment outcomes; however, the effects of extraction versus non-extraction strategies on palatal morphology in Class II malocclusions remain underexplored. This study quantified segmental palatal volume and surface changes, along with skeletal-dentoalveolar outcomes, using digital model analysis integrated with cephalometrics. Records of 69 post-pubertal patients treated with fixed appliances (Class II, n = 34; Class I controls, n = 35) were retrospectively analyzed, each subdivided into extraction and non-extraction protocols. Maxillary casts were scanned with Sirona inEos X5 and segmented in Materialise 3-Matic to compute palatal volume and surface area, while cephalometric variables were derived from lateral radiographs (Dolphin Imaging). Group comparisons were performed using non-parametric tests (p < 0.05). Multivariable regression analyses were conducted to identify dentoalveolar predictors of palatal remodeling. Intra-examiner repeatability was excellent, as indicated by a high intraclass correlation coefficient (ICC ≥ 0.90). Skeletal changes were minimal and comparable across groups. Dentoalveolar findings demonstrated significant maxillary incisor protrusion in non-extraction protocols and retrusion in extraction protocols (p < 0.05). Anterior palatal volume and surface area increased across all groups. Overall, measurable differences in total palatal volume and surface area were observed between extraction and non-extraction treatment strategies. Regression analyses indicated that sagittal dentoalveolar displacement was associated with palatal remodeling, whereas angular and vertical dental variables showed limited independent influence. Extraction and non-extraction treatment protocols were associated with measurable differences in three-dimensional palatal volume and surface area, reflecting distinct dentoalveolar and palatal remodeling patterns between treatment strategies.