Effects of impaction severity of treated palatally displaced canines on periodontal outcomes: a retrospective study

BACKGROUND: Even though periodontal health was suggested to be not related to the traction technique, some other variables might influence the esthetic outcome of palatally displaced canines (PDC) when aligned, such as the initial position and impaction rate of the canine before treatment. The purpose of the present study was therefore to evaluate the existing correlations between periodontal health outcome of PDC after their exposure and alignment and their initial position identified according to the different rates of impaction severity. MATERIALS AND METHODS: The final sample enrolled 293 PDC which satisfied inclusion and exclusion criteria. All the canines were exposed using CT by the same oral surgeon and orthodontic traction was applied using the easy cuspid device followed by fixed appliance treatment. Image analysis and periodontal status evaluation were performed for all PDCs. RESULTS: α-Angle and d-distance showed no significant differences in the periodontal outcome of PDCs after treatment. The only tested variable showing significant differences was S, since canines with CEJ visible at the end of the treatment presented sectors with a mean score of 1.67, which was significantly different (P < 0.05) when compared to the S-sector for the canines that showed PD < 2 mm at the end of the treatment. CONCLUSIONS: Radiographic variables as α-Angle and d-distance seem to not influence the periodontal outcome of the treated impacted canine regardless of the amount of gravity. On the contrary, S-sector might play a significant role when higher rates of gravity are present suggesting the possibility in few cases for periodontal damage at the end of treatment.