The treatment of an 8-year-old girl with a dilacerated maxillary incisor began in the mixed dentition; a modified palatal arch attached to the molars served as anchorage for the forced eruption of the dilacerated tooth to prevent the intrusion of the adjacent teeth and reduce the risk of root resorption. Two surgical sessions were planned: the first to permit the closed eruption; the second was an apically positioned flap to add attached gingiva to the labial side of the erupting tooth. The result was an optimal periodontal outcome; moreover, the roots of the adjacent teeth did not show any sign of resorption at the end of the forced eruption. The tooth was vital at the end of the treatment, and the apex covered by alveolar mucosa. The root developed normally throughout the treatment, and the periodontium was healthy and esthetically acceptable at the 2-year follow-up. Further study is needed to assess the advantages of the combined surgical-orthodontic treatment.
Highlights
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Root development of the dilacerated tooth was in a correct spatial relationship.
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Extrusive force was loaded onto the modified palatal arch using molar anchorage.
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Forced eruption was carried out during the exfoliation of the deciduous teeth.
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Intrusion of adjacent incisors was avoided, and root length was preserved.
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Interceptive soft-tissue management was needed for a healthy, esthetic periodontium.
Tooth dilaceration is a dental deformity characterized by noticeable angulation of the longitudinal axis of the tooth. The diagnosis is usually made early because the space for the unerupted dilacerated incisor is completely or partially lost when the contralateral permanent central incisor and lateral incisors erupt, around the age of 8-10 years. The frequency of maxillary central incisor impaction ranges between 0.006% and 0.2% in the general population , and in 1%-2% of orthodontic patients. In a sample of 64 impacted central incisors, Chaushu et al reported that 42% of the patients had impaction because of root dilaceration. A dilacerated incisor is a clinical challenge because the goal of the treatment is to restore facial aesthetics without impairing the adjacent teeth and surrounding tissues.
Early orthodontic intervention is indicated because labially impacted maxillary central incisors still have some potential for further root development if their position is corrected. , In a sample of 12 patients who had cone-beam computed tomography (CBCT) data after treatment and long-term follow-up, the inversely impacted maxillary central incisors treated had continuous and similar growth as did the mature nondilacerated incisors. The roots of the teeth treated showed increased length and a favorable apical change.
An effective multidisciplinary approach requires appropriate timing alternating surgical and orthodontic intervention. Surgical exposure followed by orthodontic traction is the most widely used approach. Although the successful alignment of the dilacerated teeth has been reported, concerns have been raised about the long-term prognosis for the dilacerated teeth that may need endodontic treatment with or without apicoectomy.
Possible dental damage includes inadequate labial gingiva and root resorption. Even after a successfully guided eruption, unattractive gingiva could occur, requiring further periodontal surgery. Multiple surgeries to improve the health and aesthetics of gingival tissues have been reported. ,
A dilacerated root makes traction complicated and can require complex orthodontic mechanotherapy; moreover, considerable anchorage is required. The shortened roots of the dilacerated tooth and adjacent teeth at the end of a successful alignment may make it impossible to proceed with the second phase of orthodontics, which may be necessary. ,
This case report presents a horizontally impacted, dilacerated maxillary left incisor treated in the early mixed dentition. The impacted incisor was successfully moved into the proper position with healthy gingiva without root resorption of the adjacent teeth using reinforced anchorage orthodontic mechanics and 2-stage surgical crown exposure. The periodontal surgical procedures and the orthodontic strategies for treating the impacted dilacerated maxillary central incisor are discussed.
Case report
An 8-year-old girl was referred for orthodontic consultation regarding an unerupted permanent maxillary left central incisor. The patient was in the early mixed dentition, with a Class II Division 1 malocclusion. There was space loss with the drift of the right incisor toward the region of the unerupted tooth, causing a midline deviation; crossbite was evident on the left side ( Fig 1 ).
The child was physically healthy and had no history of systemic conditions or dental trauma. There was no sign of caries or periodontal disease.
A panoramic x-ray and lateral cephalogram revealed that the permanent maxillary left incisor was dilacerated, positioned horizontally with the crown being inverted; its incisal edge was near the apex of the right central incisor and just below the nasal cavity ( Fig 2 ).
The parents were informed of the treatment plan, the duration of treatment, the risk of failure, and the possible need for additional surgery.
A rapid maxillary expander (RME) was placed; the bands were cemented to the deciduous maxillary second molars, which had complete root formation. RME was maintained for 6 months. Fixed appliances were bonded to the incisors, deciduous canines, and deciduous molars. An 0.014-in nickel–titanium archwire, then an 0.018-in stainless steel wire, and a nickel–titanium open-coil spring were applied between the maxillary right central incisor and the left lateral incisor for initial alignment. The duration of this phase was 9 months and made it possible to correct the crossbite, to center the midline and obtain adequate space for the dilacerated incisor.
CBCT imaging was done to ascertain the relationship between the impacted tooth and the neighboring apex. The dilacerated incisor was horizontal, situated below the floor of the left nasal cavity, with its incisal edge just ahead of the anterior nasal spine, about 5 mm beyond the labial cortical bone. The pulp canal was wide open at the root apex, showing a tooth still in formation. The root of the impacted incisor was short in comparison with the maxillary right central incisor, with the apical third of the root dilacerated near the palatal cortical bone (100° crown-root angle). No alterations were found in the neighboring teeth, although contact between the impacted incisor and the maxillary left lateral incisor was observed ( Fig 3 ).
Once the alignment was complete, and space had been gained, a mucoperiosteal flap was raised after a crestal incision, and the palatal side of the crown of the dilacerated tooth was exposed under local anesthesia. A gold bracket with an attached chain was bonded to the palatal surface of the tooth. The gold chain was secured to the maxillary arch. A ligature wire was tied to the main archwire with an elastic thread. The flap was repositioned and closed with absorbable synthetic surgical sutures ( Fig 4 ).
Elastic traction was applied to the initial archwire for 3 weeks. The anchorage was reinforced by a fixed 0.080-in stainless steel palatal arch with a loop bent at the center of the created space. The palatal arch was soldered to the palatal surfaces of the bands on the maxillary first molars ( Fig 5 ).
The closed-eruption technique was performed from the buttonhole toward the alveolar crest to promote a physiological pattern of eruption. An elastic thread was tied to the bent loop on the soldered arch and replaced every 15 days. A light force of approximately 60 g was applied. No segmental or continuous arches were used on the lateral and central incisors during the extrusive phase.
Even though the deciduous molars and canines were exfoliating, the gold chain remained attached to the palatal arch. Tooth movement and soft-tissue status were monitored every 2 weeks.
The incisal edge of the dilacerated tooth was visible through the alveolar mucosa, although it had not been perforated 5 months after surgery ( Fig 5 ).
A second surgery was performed when the mucosa overlying the incisal edge became excessively transparent because of the risk of perforation of the alveolar mucosa: a combined full and/or partial-thickness flap was raised. The gingiva was transferred over the crown of the dilacerated tooth and secured to the periosteum in the partial-thickness portion apically to the incisal margin of the impacted tooth ( Fig 6 ). A button was bonded to the facial surface of the crown, and a vertical metallic chain attached.
