Dentigerous cysts are slow growing benign and non-inflammatory odontogenic cysts that are thought to be developmental in origin.

On imaging, they usually present as a well-defined and unilocular radiolucency surrounding the crown of an unerupted or impacted tooth within the mandible. 

Differential diagnosis

When small, it is difficult to differentiate a dentigerous cyst from a large but normal dental follicle. When larger, the differential is essential that of lytic lesions of the jaw and includes:

• periapical cyst (radicular cyst)
• aneurysmal bone cyst (ABC)
• ameloblastoma
• keratocystic odontic tumor (odontogenic keratocyst)
• cherubism (fibrous dysplasia)
• Stafne cyst