Pulpal and periodontal reactions to orthodontic alignment of palatally impacted canines

The purpose of this study was to evaluate differences in periodontal and pulpal status, root length, and tooth alignment between contralateral maxillary lateral incisors, canines, and premolars in patients treated for unilateral impaction of maxillary canines. Clinical examinations were performed on 32 patients, average age 22 years 11 months and average posttreatment observation period 3 years 7 months. Probing attachment level was lower at the mesial and distal aspect of the previously impacted canine and at the distal aspect of the adjacent lateral incisor. Crestal bone height was lower at the mesial aspect of the previously impacted canine and at the distal aspect of the adjacent lateral incisor. The roots of the lateral incisors and premolars adjacent to the previously impacted canines were shorter. Pulpal obliteration was observed in six previously impacted canines (21%), and pulp necrosis in one previously impacted canine. The pulps of the remaining teeth appeared normal radiographically. A negative response to electric pulp testing was observed in eight previously impacted canines. Approximately 40% of the previously impacted canines exhibited noticeable relapse and were judged to be intruded, lingually displaced, mesially rotated, as well as discolored. Of the contralateral canines, 91% were normal in appearance. The previously impacted canine could be identified on posttreatment color slides in approximately 75% of the cases.

Two patients with severely displaced maxillary canines respond differently to treatment

The patient with a severely displaced maxillary canine continues to challenge the orthodontic specialist. When the two patients in the following case reports presented, their problems seemed similar: each had a palatally displaced canine. However, unique clinical problems were soon diagnosed that led to the development of different treatment approaches. These differences are worth discussing, especially in light of newly published studies. In planning treatment for these two patients, the following questions are worth considering. 1. Is it common for other dental anomalies (small lateral incisors, missing teeth) to occur more frequently in patients with palatally displaced canines? 2. Following surgical exposure of palatally displaced maxillary canines, how significant are the risks of tooth movement with regard to periodontal health, vitality, and retention? 3. Are new or improved surgical procedures becoming available to bring severely impacted teeth into alignment? 4. When planning ahead to replace a missing premolar with an endosseous implant, is it better to retain the primary molar as long as possible or extract it during treatment? 5. How stable is the closure of a maxillary median diastema years after a reasonable period of retention?