Читать книгу Orthodontic Treatment of Impacted Teeth - Adrian Becker - Страница 109

In cases where displacement of the canine has been caused by crowding or space loss (following early extraction of deciduous teeth), it is clear that relief of the crowding will facilitate spontaneous improvement in the position of the canine. However, time may not be on the side of the clinician who opts for this approach, since if there is too much delay the tooth may erupt through the oral mucosa. Nevertheless, if it is decided to proceed with this approach, a full case analysis should be prepared, leading to a diagnosis and treatment plan for the overall malocclusion. If, while the treatment is proceeding, the crowding is to be dispersed by distal movement of the molars, it will take longer to achieve the requisite available space in the canine region to permit the spontaneous improvement of the canine position. On the other hand, a premolar extraction will provide immediate relief of the crowding and an excellent opportunity for a self‐correction of the buccal displacement, and with it the disappearance of the potential periodontal hazard.

In the treatment of a palatally impacted maxillary canine, a buccal approach to solving the crowding may sometimes be preferred, provided that its palatal displacement from the line of the arch is fairly minimal. Where the impacted tooth is vertically close to the CEJs of the adjacent teeth, the buccal approach may present a risk that interproximal bone may thereby disappear. Indeed, the greater the palatal displacement of the tooth, the greater will be the bony defect caused. Nevertheless, the buccal approach may be appropriate in cases where the teeth are marginally palatally displaced and situated higher in the maxilla. This will afford the opportunity for traction of the tooth by a more direct route to the labial archwire.

Impaction of the maxillary canine, close to the line of the dental arch, may have been caused by the mesially tipped long axis that it presents, and by the consequent direct contact of the mesial crown incline with the distal side of the root of the lateral incisor. This type of impaction is relatively simple to treat. Indeed, it should correct itself if the crown of the lateral incisor is tipped mesially, thereby closing the anterior spacing and providing room for the canine within the arch. The process will automatically cause the root apex of the incisor to move distally, coordinating the orientation of its long axis with that of the canine. If, however, the tooth maintains its stubbornness and shows no sign of erupting, then a labial surgical approach to the very mildly palatally displaced canine will often be the most suitable and, in terms of the traction, the most direct treatment.