Maxillary canines are the second most commonly impacted teeth. Two thirds of these impacted canines are palatal, and one third are labially impacted. Maxillary labial impactions comprise approximately 0.33% to 0.75% of the general population. Like palatal impactions, preventive and interceptive methods can be employed to help the impacted tooth erupt and avoid surgical uncovering. Early extraction of appropriate primary teeth and palatal expansion has helped some of these impactions erupt spontaneously. Most labially impacted canines are positioned "in the slot," in a midalveolar location between the lateral incisor and first premolar. If they do not erupt after preventive or interceptive means, they can be managed with simple closed-eruption uncovering techniques. The most difficult labial impactions are ectopically positioned. These are usually horizontally positioned, mesial to the lateral incisor. They can be very apically positioned, near the base of the nose and near the midline. The rarest labial impaction occurs between the central and lateral incisors or between the premolars. These are extremely rare and require special orthodontic and uncovering techniques. All of these ectopic impactions require a technique that leaves the impacted tooth uncovered so the orthodontist can employ the proper mechanics to move these teeth without damage to adjacent structures. This article elucidates the surgical uncovering techniques and the orthodontic mechanics to successfully move these teeth and minimize root resorption, bone loss, and recession.
