Alveolar bone response to maxillary incisor retraction using stable skeletal structures as a reference

To evaluate alveolar bone change in relation to root position change after maxillary incisor retraction via cone-beam computed tomography (CBCT) using stable skeletal structures as a reference.

A total of 17 subjects (age 24.7 ± 4.4 years) who required retraction of the maxillary incisors were included. Labial and palatal alveolar bone changes and root change were assessed from preretraction and 3 months postretraction CBCT images. The reference planes were based on stable skeletal structures. The Kruskal-Wallis test and Wilcoxon signed-rank test were used to compare changes within and between groups, as appropriate. Spearman rank correlations were used to identify the parameters that correlated with alveolar bone change. The significance level was set at .05.

The labial alveolar bone change after maxillary incisor retraction was statistically significant (P < .05), and the bone remodeling/tooth movement (B/T) ratio was 1:1. However, the palatal bone remained unchanged (P > .05). The change in inclination was significantly related to labial alveolar bone change.

Using stable skeletal structures as a reference, the change in labial alveolar bone followed tooth movement in an almost 1:1 B/T ratio. Palatal alveolar bone did not remodel following maxillary incisor retraction. The change in inclination was associated with alveolar bone change.