Periodontal response to early uncovering, autonomous eruption, and orthodontic alignment of palatally impacted maxillary canines

Introduction: The purpose of this study was to evaluate differences in periodontal status, root length, and visual assessment in patients with palatally impacted maxillary canines that were surgically exposed, allowed to erupt freely into the palate, and orthodontically aligned. Methods: Clinical examinations of the maxillary lateral incisors, canines, and adjacent premolars were performed on 16 patients with unilaterally impacted canines and 6 with bilaterally impacted canines treated in this manner. The average age was 23 years 7 months, and the average posttreatment observation period was 2 years 11 months. Data from the bilaterally impacted canines were not used in the central analysis. Results: Differences in probing attachment level were found at the distolingual region of the lateral incisor and at the distobuccal region of the premolar adjacent to the treated canine. Crestal bone height was lower at the mesial and distal regions of the lateral incisor adjacent to the previously impacted canine, and the roots of the treated canine and adjacent lateral incisor were shorter than those of the contralateral control teeth. Twenty-three orthodontists and 9 second- and third-year orthodontic residents could identify the previously impacted canine in the unilateral patients an average of 78.9% of the time, but to a statistically significant degree in 66% of all patients. Conclusions: The overall consequences to the impacted canine of surgical exposure and free eruption are good compared with closed exposure and early traction, whereas consequences to the adjacent teeth, particularly the lateral incisor, are similar. Future research directly comparing the 2 methods with a larger sample and randomization could yield further insight.