A CBCT study on Morphological characteristics of dental arches in subjects with unilateral maxillary canine impaction.

Objective To examine the relationship between unilateral maxillary canine impaction and the morphological characteristics of the maxillary dental arches using Cone beam computed tomography(CBCT). Methods 39 patients with unilateral impacted canine were selected, including 19 palatal impaction (UPI)(mean age: 16.21±4.14 years) and 20 buccal impaction (UBI). 20 normal patients served as control, with matched ages. CBCT images for the three groups were taken and compared for arch characterestics. Results The anterior and whole dental arch lengths of impaction side were smaller than that of normal sides (P<0.001). The first molar to midpalatal suture distances of UPI group were smaller than the other groups and the arch perimeter of it was smaller than UBI group(P<0.05). Conclusions The short arch lengths (especially in anterior part) may have effect on the occurrence of unilateral maxillary canine impaction. UPI may also be related to a smaller arch width. Key words: Unilateral maxillary canine impaction; Dental arch morphology; CBCT