[Dentigerous cyst. Review of the literature and report of a case].

A case of circumferential dentigerous cyst is presented, with a review of the literature. This lesion occurs when the tooth is exfoliated through the cystic epithelium surrounding a crown, so that the cyst remains within the cervical third. When these teeth are extracted without previous diagnosis, the cyst could become residual. In all dentigerous cyst, the microscopic features must be determined, since some reports mention their eventual transformation in an ameloblastoma or, even worse, in a squamous-cell carcinoma.