Assessment of the positional and morphological differences of unilaterally impacted canines: A cross-sectional study

This study aimed to use cone beam computed tomography (CBCT) to evaluate the dimensional and morphological characteristics of unilaterally impacted canines, their effects on adjacent teeth, and differences with contralaterally erupted canines.

A sample of 31 patients (22 males, mean age 22.22 ± 4.82 years; 9 females, mean age 23.91 ± 5.16 years) with unilaterally impacted maxillary palatal teeth were included in the study. CBCT images were obtained using a NewTom 5 G unit in standard mode. Three-dimensional multiplanar reconstructions emulating a panoramic view and curved planar reconstructions were evaluated. Individuals were divided into two groups (low- and high-complexity) according to Ericson and Kurol's impaction complexity classification.

The crown lengths and mesiodistal crown widths of the impacted canines were similar to the symmetric canine on the opposite arch and significantly larger than adjacent lateral and premolar teeth (p<0.05). The alpha (31.33 ± 8.32) and beta angles (39.53 ± 10.31) and the 'h' height (10.11 ± 2.02) values in the low-complexity group were significantly lower than the high-complexity group (alpha angle=57.40 ± 12.15; beta angle=71.31 ± 13.94; 'h' height=14.35 ± 3.71, and alpha angle: p<0.001; beta angle: p<0.001; 'h' height: p=0.002) CONCLUSION: The root lengths of impacted maxillary canine teeth are significantly shorter than symmetrically erupted canine teeth regarding labiolingual crown width. As the alpha and beta angles and 'h' height increase, the complexity level of the impacted canine also increases.