Three-dimensional evaluation of dentofacial transverse widths of adults with various vertical facial patterns

Introduction: The purpose of this study was to investigate maxillomandibular transverse widths and molar inclinations of adults with hypodivergent, normodivergent, and hyperdivergent facial patterns using cone-beam computed tomography. Methods: We evaluated Class I subjects (55 men, 66 women) who were divided into hypodivergent (<27°), normodivergent (28°-37°), and hyperdivergent (>38°) groups by their mandibular plane angles. Frontal and coronal views of the images were analyzed. Sex differences, vertical facial pattern differences, and related factors were assessed with independent 2-sample t tests, 1-way analysis of variance followed by post hoc Tukey tests, and Pearson correlation analysis. Results: The hypodivergent group had greater maxillary alveolar widths 7 mm apically from the alveolar crest. The intermolar widths and molar inclinations showed no significant differences among the groups. As the mandibular plane angles increased, interjugular widths, transverse mandibular widths, and buccolingual maxillary alveolar widths at the midroot level decreased, whereas the maxillomandibular width differences and palatal heights increased im both sexes. Conclusions: An increase in the mandibular plane angle is associated with tendencies of narrow mandibular arches, thinner maxillary alveolar bones at the midroot level, and higher palatal arches in both sexes. Intermolar widths and molar inclinations were not significantly affected by vertical facial patterns.