Evaluation of Periodontal Changes Adjacent to Extraction Sites during Upper Canine Retraction.

Introduction: There is an intimate relationship between orthodontic therapy and the periodontal changes that occur during tooth movement.

Materials And Methods: This prospective clinical trial aims at investigating the movement of both the free and attached gingiva, as well as the movement of the alveolar bone in the extraction site of the upper 1st premolars during the retraction of the upper canines. In this study, 17 patients (10 female, 7 male) requiring 1st premolar extraction before orthodontic tooth movement were selected and treated at the Department of Orthodontics in the Faculty of Dentistry in University of Hama, Hama, Syria. The upper 1st premolars were extracted, and the implant AutoTacs were applied on the alveolar bone afterward. Then, measurements between the center of the implant AutoTacs and the L-shape wire were taken, utilizing digital Vernier caliper. After 3 weeks of extraction, tattooing marked points were placed on the free and the attached gingival, and the measurements were taken using the same digital Vernier caliper. Closed coil springs made of nickel-titanium were used to retract the upper canines, and a force of 150 gm was applied.

Results: The results of this study showed significant differences between the movement of both the free and attached gingiva and the movement of the corresponding upper canines (p < 0.001). The movement of the free gingiva had formed about 77% of the amount of the movement of the upper canine retraction. No significant differences were detected between the place of implant AutoTac X1 and the L-shaped wire (W) during the retraction of the upper canine. On the contrary, significant differences were noticed between the place of implant AutoTac X2 and the L-shaped wire (W) during the retraction of the upper canine (p < 0.001).

Conclusion: There is significant movement of hard and soft tissues during and after premolar extraction and orthodontic therapy.

Clinical Significance: The movement of supporting tissues of the teeth along with the alveolar bone during canine retraction is an important biological characteristic of the orthodontic tooth movement. Clinicians need to understand the role and importance of the supporting tissues during orthodontic treatment, which needs to be incorporated into their routine clinical evaluations.