Benign-Appearing Bone Lesions Associated with Teeth

This is a relatively short differential for benign-appearing bone lesions associated with teeth:

• Radicular cyst: Small vperiapical cyst associated with an erupted carious tooth. Dentigerous cysts and radicular cysts tend to be oriented in a superoinferior plane, as opposed to keratocysts, which are oriented in the plane of the mandible.
• Dentigerous cyst: Well-circumscribed, expansile cyst surrounding the crown of an unerupted, embedded or impacted tooth. Dentigerous cysts and radicular cysts tend to be oriented in a superoinferior plane, as opposed to keratocysts, which are oriented in the plane of the mandible.
• Ameloblastoma (above image): Locally invasive, but benign with extensive thinning of the bone. Usually multilocular, but can be unilocular in 20% of cases. A Bubbly pattern is characteristics, but not specific. As seen in the above image, it can have an appearance similar to dentigerous cysts, and may be associated with an unerupted molar tooth. May be associated with erosion of tooth roots.
• Keratocyst: Uni- or multi-loculated. Expansile cyst. May have a cloudy appearance. Seen in Gorlin (basal cell nevus) syndrome. In contrast to dentigerous cysts and radicular cysts, which tend to be oriented in a superoinferior plane, it is said that keratocysts are oriented in the plane of the mandible. May displace developing teeth with or without resorption of roots of erupted teeth.
• Adenomatoid odontogenic tumor (AOT): Usually in the anterior maxilla in association with the crown of unerupted tooth.
• Giant cell granuloma:

Some broad generalizations: