Periodontal outcome of buccally impacted maxillary canines after orthodontic traction following closed eruption technique

Abstract

The aim of this investigation was to evaluate the periodontal status of the buccally impacted maxillary canines after orthodontic traction following closed eruption technique by clinical and radiographic methods and to investigate pre-treatment orthodontic variables affecting the periodontal changes. 54 patients (21 males and 33 females) having one maxillary canine in a buccally impacted position was choosed (impaction group) and a contralateral canine in a normal position served as a control group. Probing depth, bone probing depth, keratinized gingiva width, attached gingiva width, clinical crown length, distance from cemento-enamel junction (CEJ) to alveolar crest (AC) and bone support were measured at 1.4 months after the end of treatment. The following results were observed.1. Probing depth on midbuccal and mesiolingual sides was significant increased in the impaction group (mean difference 0.20 mm, 0.25 mm, respectively, P <0.05). Bone probing depth on mesiolingual and distolingual sides was increased in the impaction group than the control group (mean difference 0.24 mm, 0.48 mm, respectively, P < 0.05).2. The attached gingiva width was significant shorter in the impaction group compared to the control group (mean difference 0.62 mm,P < 0.01). The buccal clinical crown length was longer on the impaction group than the control group (mean difference 1.12 mm, P < 0.001).3. The distance from CEJ to AC was significant longer in the impaction group on mesial and distal sides compared to the control group (mean difference 0.89 mm, 0.82 mm, P < 0.001). There were significant smaller bone supports at mesial and distal sides in impaction group compared to control group (mean difference 7.30%, 8.80%, P < 0.001).4. If the impacted canine was localized at the more mesial angulation (to the horizontal) and the deeper from occlusal plane at the beginning of treatment, the distance from CEJ to AC on distal side was increased significantly at the end of treatment (P < 0.01). These results revealed that forced eruption of the maxillary impacted canine after orthodontic traction following closed eruption technique, resulted in significant gingival recession on the buccal side and alveolar bone loss on the interproximal sides. Initial intraosseous position and the inclination of impacted canine were related with the periodontal changes.