Summary:
This lesion is a well-circumscribed radiolucent lesion with a corticated
border surrounding the crown of an unerupted third molar.
Lesions to Include/Exclude:
Exclude primary diseases of bone because they are located in multiple
areas of the skeleton.
Exclude inflammatory diseases because they will be associated with a
source or focus for an inflammatory response, such as a non-vital tooth,
periodontal disease, or fracture. Inflammatory lesions may be symptomatic.
Exclude malignant neoplasms because they are poorly circumscribed and
may cause pain and/or paresthesia.
Exclude benign non-odontogenic tumors because they will not be intimately
associated with the crown of an unerupted tooth.
The history and radiographic features of the lesion in this case are
strongly suggestive of an odontogenic cyst or benign odontogenic tumor.
The most likely diagnosis of this lesion is dentigerous cyst, which is
defined as a cyst arising from the reduced enamel epithelium surrounding
the crown of an unerupted tooth.
Always include certain benign odontogenic tumors in the differential
diagnosis when a lesion appears similar to a dentigerous cyst. In this
case include ameloblastoma, ameloblastic fibroma, and central odontogenic
fibroma. Also include lesions with a variable radiolucent-radiopaque appearance,
including adenomatoid odontogenic tumor, calcifying epithelial odontogenic
tumor, calcifying odontogenic cyst, and ameloblastic fibro-odontoma.
Exclude the following benign odontogenic tumors:
Exclude periapical cemental dysplasia because it is located in the periapical
region of one or more teeth.
Exclude odontoma and benign cementoblastoma because these lesions are
radiopaque.
Management:
Treatment for this lesion is surgical excision because that will provide
a definite microscopic diagnosis and may be curative. Microscopically
the lesion consisted of a wall of fibrous connective tissue lined by nonkeratinized
stratified squamous epithelium. It was diagnosed microscopically as dentigerous
cyst.
Prognosis:
Complete excision results in cure. Recurrence is not expected, but the
patient should receive follow-up of the area.