Extensive nasopalatine duct cyst causing nasolabial protrusion.

In this report, we show a case of the extensive nasopalatine duct cyst showing remarkable nasolabial protrusion. CT and MR examinations showed remarkable expansion of the extraosseous part of the lesion toward anterior and lateral sides, and this finding is considered to show the rather aggressive nature of this common cystic lesion after penetration of the maxillary cortex.