Maxillary lateral incisor morphology and palatally displaced canines: a case-controlled cone-beam volumetric...

The goal of this study was to compare the dimensions of maxillary lateral incisors in subjects with and without palatally displaced canines.

An experimental group of 40 patients with 46 palatally displaced canines (20 in boys, 26 in girls; mean age, 13.9 years; range, 10.5-15.9 years) was selected from the records of patients referred to a radiology practice specializing in cone-beam volumetric tomography imaging. The palatally displaced canine group was age- and sex-matched with 30 normal subjects with 60 canines (26 in boys, 34 in girls; mean age, 13.8 years; range, 10.4-15.7 years). Cone-beam volumetric tomography DICOM files were imported into Dolphin Imaging software (version 11.0; Dolphin Imaging & Management Solutions, Chatsworth, Calif), and the volumetric images were reoriented with the long axis of the lateral incisor vertical and then reconstructed into images of a sagittal slice through the maxillary lateral incisors and 3 axial slices across the maxillary lateral incisor root. The linear variables of the maxillary lateral incisors were measured by using digital measurement tools. The widths of the maxillary lateral incisor roots were registered at the cementoenamel junction level, 4 mm apical to the cementoenamel junction level and 8 mm apical to the cementoenamel junction level. An independent t test was used to test for differences between the groups, because the data were normally distributed.

In the group with palatally displaced canines, the mean length of the maxillary lateral incisors was 2.1 mm shorter (P <0.001), and the mean root width was smaller, especially in the buccolingual dimension, by 0.7 mm (P <0.001).

Lateral incisors adjacent to palatally displaced canines were smaller compared with those adjacent to normal canines.