Comparison of three-dimensional reconstructed palatal morphology in skeletal Class III and skeletal Class I subjects with different vertical patterns

Abstract

Abstract Objective: This study aims to evaluate the difference of palatal morphology between subjects with skeletal Class III and skeletal Class I in different vertical patterns using digital technology. Materials and Methods: In this study, 89 subjects with skeletal Class III (49 females, 40 males; 25.45±3.81 years) and 85 subjects with skeletal Class I (45 females, 40 males; 23.95±4.45 years) were collected retrospectively and divided into hyperdivergent, normodivergent and hypodivergent groups. Dolphin software was used to reorient the CBCT images of these subjects. After using ProPlan software to segment three-dimensional (3D) object of maxilla from the 3D skull, Geomagic Studio software was used to reconstruct 3D palatal morphology. The differences of 3D palatal morphology between different groups were compare by deviation patterns on 3D colored map analysis. Results: 3D colored map analysis showed the posterior part of male’s palate was higher and wider than that of female in skeletal Class III subjects. In skeletal Class III subjects, males with hyperdivergent had a higher and narrower palate compared with hypodivergent subjects, while females with hyperdivergent had a higher but no obvious narrower palate compared with hypodivergent subjects. In the similar vertical patterns, skeletal Class III subjects had a flatter but not narrower palate compared with skeletal Class I, along with a smaller palate volume. Conclusions: In skeletal Class III subjects, as the vertical dimension increased, the palate tended to be higher and narrower. Clinical Relevance: The influence of vertical patterns on the palatal morphology should be fully considered in the orthodontic and orthognathic treatment of skeletal Class III subjects.