Transmigrant impacted mandibular canines: a retrospective study of 15 cases.

Background: Transmigration of mandibular canines across the midline is rare. The authors describe the clinical and radiologic characteristics of patients with transmigrant impacted mandibular canines.

Methods: The authors conducted a retrospective observational study of 14 patients with transmigrant canines. They diagnosed transmigrant canines in all of the patients on the basis of the clinical and radiological findings, and they obtained the data from the patients' case histories and panoramic radiographs. They considered a canine to be transmigrant when one-half or more of its length crossed the mandibular midline.

Results: There were 15 transmigrated canines in 14 patients aged 16 to 60 years. Primary canines were present in 10 cases. One case involved a pericoronal infection, two involved supernumerary teeth, one was associated with an odontoma, and in two a pericoronal radiolucency was seen that was compatible with a follicular cyst. Treatment consisted of surgical extraction for eight patients, and periodic clinical and radiologic follow-up visits for six patients.

Conclusions: Radiographic examination is necessary to diagnose impacted transmigrant canines, among other anomalies. Surgical extraction is the treatment of choice for patients with transmigrant canines involving associated pathology. In some cases, the management of asymptomatic impaction can be limited to periodic clinical and follow-up visits.

Clinical Implications: The absence of the permanent canine within the arch beyond the normal time of eruption suggests the presence of an impacted canine. A transmigrant canine may develop an associated pathology.