Cone-beam computed tomographic evaluation of changes in maxillary alveolar bone after orthodontic treatment

This study examined the relationship of vertical and horizontal changes in the alveolar bone crest with upper incisor movement after orthodontic treatment. Tooth movement was measured on lateral cephalograms. Vertical and horizontal changes in the median alveolar crest and distance from the cementoenamel junction and anterior nasal spine to the alveolar crest were measured with cone-beam computed tomography. The incisal edge moved distally, and the cervical point intruded significantly and moved distally. The median alveolar crest decreased by 3.80 ± 2.05 mm. The distance from the labial cementoenamel increased significantly, by 0.35 ± 0.38 mm. The vertical distance from the anterior nasal spine decreased significantly, and the alveolar crest moved distally. Vertical tooth movement was positively associated with change in the distance from the labial cementoenamel junction and inversely associated with vertical change in the distance from the anterior nasal spine on the labial and palatal sides. Lingual tooth movement was positively and negatively correlated with horizontal changes in the labial and palatal alveolar crest and vertical change in the palatal alveolar crest. The lingual movement of incisors was related to labial bone resorption. Greater lingual and extrusive movement of incisors led to a greater decrease in the alveolar bone crest.