Unusual evolution of a residual dental cyst: a giant rhinolith.

Rhinoliths are calcareous concretions, consisting mainly of calcium and magnesium carbonates and phosphates. They can vary in size and shape, from small bodies to massive growths, and may invade adjacent structures. A 75-year-old female with a history of purulent discharge, nasal obstruction, and headache was observed in the ENT Department, University of Rome "Tor Vergata". Clinical examination revealed a giant rhinolith completely obstructing the right nasal cavity. Curiously, a dental CT scan showed a bony destruction area related to a residual dental cyst that had migrated superiorly into the maxilla. A transnasal, surgical approach was performed, and the rinolith was completely removed under local anaesthesia. The authors suggest that the giant rhinolith could have an odontogenic origin and that it could be an unusual complication of residual dental cyst.