Correlation between panoramic radiography and cone-beam computed tomography in assessing maxillary impacted canines

Abstract

Objective: To determine the usefulness of panoramic radiographs in determining the labio-palatal position of maxillary impacted canines (MICs) and root resorption of permanent incisors on cone-beam computed tomography (CBCT) in correlation with the mesiodistal position of MICs on panoramic radiographs.

Materials and methods: This retrospective radiographic study reviewed 64 patients with 86 MICs. Subjects were divided into two groups: group I (<15 years old) and group II (>15 years old). The mesiodistal position of the MICs' cusp tips was classified into five sectors on panoramic radiographs. The labio-palatal position of the MICs and root resorption of permanent incisors were evaluated on CBCT. The statistical correlation between panoramic radiograph and CBCT results was examined using the chi-square test and the Fisher exact test.

Results: Most of the positions of MICs were palatal (67%), followed by labial (28%) and mid-alveolus (5%; P < .05). Labial positioned MICs on CBCT were more frequent in panoramic sector 1, mid-alveolus MICs were more common in sector 2, and palatally positioned MICs were more frequent in sectors 3, 4, and 5. The association between sectors of the MICs on panoramic images and the labio-palatal position of the MICs on CBCT was statistically significant ( P < .001). Root resorption of adjacent incisors showed a significant difference according to sector location ( P < .01) and was mainly found in sectors 4 and 5.

Conclusions: This study showed that the labio-palatal position of MICs and resorption of permanent incisors might be predicted using sector location on panoramic radiographs.

Keywords: CBCT; Impactions; Maxillary canines; Pantomogram; Resorption.

Figure 1

The mesiodistal position of the canine tip in relation to adjacent teeth was used to determine sector locations on the panoramic radiograph.

Figure 2

(a) Partial Panorex was generated from the CBCT and static cross-sectional images were obtained to show where the maxillary impacted canine was positioned. (b) The labio-palatal position of maxillary impacted canines was assessed in static cross-sectional reformatted images of the CBCT.