Eruption of an impacted second premolar after marsupialization of a large dentigerous cyst: case report.

Dentigerous or follicular cysts are one of the most prevalent types of odontogenic cysts and are associated with the crown of an unerupted or developing tooth.' The cyst enclosing the crown of the unerupted tooth also is attached to the tooth along the cervical region. The teeth most often involved are mandibular third molars, maxillary canines, and mandibular premolars. Usually, dentigerous cysts begin to develop through an accumulation of fluid between the remnants of the enamel organ and the subjacent tooth crown shortly after complete formation of the crown. The expansion of dentigerous cysts is related to a secondary increase in cyst fluid osmolality as a result of passage of inflammatory cells and desquamated epithelial cells into the cyst lumen. In rare cases, the dentigerous cyst develops as a result of the intrafollicular spread of periapical inflammation from an overlying primary tooth.The purpose of this report is to describe a case of a large dentigerous cyst that impacted a second premolar, which erupted naturally after marsupialization of the cyst.