Evaluation of alveolar bone dimensions in unilateral palatally impacted canine: a cone-beam computed tomographic analyses

The purpose of this study was to evaluate the alveolar bone dimensions and arch perimeter discrepancy in unilateral palatally impacted canines. This retrospective split-mouth study reviewed 207 cone-beam computed tomography (CBCT) scans of patients with unilateral or bilateral impacted canines referred for orthodontic treatment. Out of 207 CBCT scans, only 39 scans in which canines were unilaterally palatally impacted were approved for the study based on our inclusion and exclusion criteria. Two fiducial lines were used to orient the examiners and standardize the measurements. Arch perimeter, buccopalatal (BP) width, and alveolar height were measured both on the impacted and non-impacted side. Two different examiners measured all the parameters. A one-sample Kolmogorov-Smirnov test was used to examine normality of distribution of outcomes. Wilcoxon Signed Rank tests were used for comparing arch width and alveolar bone height between the impacted and non-impacted sides. For arch perimeter, the paired-sample t-test was used. The arch perimeter, BP width, and alveolar bone height was significantly decreased on the impacted side (P < 0.05). The mean arch perimeter on the impacted side was 41.7 +/- 2.5mm compared to 43.5 +/- 2.37 on the non-impacted side. Similarly, BP width and alveolar bone height on the impacted side was 6.87 +/- 1.08mm and 18.12 +/- 2.28mm, respectively, whereas on the non-impacted side was 8.70 +/- 1.13mm and 19.49 +/- 2.09mm, respectively. There was a significant decrease in the arch perimeter and alveolar bone dimensions (BP width and alveolar bone height) on the impacted side.