Unicystic Ameloblastoma in a Child Treated with a Combination of Conservative Surgery and Orthodontic Treatment: A Case Report.

Unicystic ameloblastoma (UAM) is a variant of intraosseous ameloblastoma that occurs as a single cystic cavity. This report describes a case of UAM of the mandible in a seven-year-old girl. The lesion radiographically mimicked a dentigerous cyst. Under the primary diagnosis of a dentigerous cyst, marsupialization was performed to erupt the first molar involved in the cystic lesion and to obtain a definitive diagnosis. The biopsy specimen revealed ameloblastoma. During careful observation, orthodontic treatment, which was performed to upright and promote the eruption of the first molar involved in the tumor, maintained the space needed for enucleation of the tumor. Finally, the second primary molar was extracted, and the lesion was enucleated at 3 years and 4 months after marsupialization. The results of the histological examination revealed UAM. Conclusively, the treatment course not only avoids a resection of the mandible but also induces eruption of the teeth involved in the tumor. Thus, the combination of conservative surgery and orthodontic treatment was effective in the management of UAM that mimics a dentigerous cyst.