Three-Dimensional Analysis of Alveolar Bone Morphological Characteristics in Skeletal Class II Open Bite Malocclusion: A Cone-Beam Computed Tomography Study

This cross-sectional research evaluated the morphological characteristics of alveolar bone in skeletal class II open-bite individuals compared to skeletal class II and class I non-open-bite individuals. A sample of 82 patients (all were in cervical vertebral stage 6) was divided into three groups (class II OB group, n = 29; class II NOB group, n = 29; class I NOB group, n = 24) according to bilateral molar relationship, ANB angle, and anterior overbite measured by cephalometric analysis. The evaluation was performed with specialized software (Mimics 21.0) and initial cone-beam computed tomography (CBCT) data. The alveolar bone height and thickness of the whole dentition area and alveolar crest level and root apex position of the incisors were measured with a series of appropriate CBCT images. One-way analysis of variance followed by the Tukey post hoc test and the Kruskall–Wallis test were performed for statistical comparisons. The class II open-bite group had increased alveolar bone height for the maxillary first molar and decreased alveolar bone height for mandibular molars compared to the class II non-open-bite group (p < 0.05 for both). Furthermore, there were significant negative correlations between the alveolar bone heights of the upper first and second molars (A6-height, A7-height) and overbite (both p < 0.01). The alveolar thicknesses of all measured teeth were generally reduced in the class II OB group.