Maxillary unicystic ameloblastoma: A review of the literature

Abstract

The term unicystic ameloblastoma (UA) refers to those cystic lesions that show clinical, radiographic, or gross features of a jaw cyst, but on histologic examination show a typical ameloblastomatous epithelium lining part of the cyst cavity, with or without luminal and/or mural tumor growth. Although the histology suggests that cystic ameloblastomas follow a biologically low-grade course, recent evidence suggests that they may often behave clinically as aggressive tumors. This is supported by the high incidence of cortical perforation, tooth resorption, increase in lesion size, bony destruction, and a high rate of recurrence after simple enucleation. Here, the authors present a case report on unicystic variant of ameloblastoma in the maxilla. An attempt has been made to emphasize that it can involve the maxillary jaw, which is rarely affected and could be more aggressive than previously thought. A literature review on the topic has been added along with the case report. It is important to remember that a proper and timely diagnosis of the character and extent of a UA (with a thorough histopathologic examination of the entire specimen) can help in the overall long-term well-being of the patient.

Unicystic Ameloblastoma Presenting as a Multilocular Radiolucency in the Anterior Mandible: A Case Report

“… 10 Our case was a non-dentigerous variant and also presented as a multilocular radiolucency in the anterior mandible crossing the midline, which is rather uncommon for these lesions. The present case was also diagnosed in an older individual (45 years of age) consistent with Singh et al, 6 who stated that the ‘non-dentigerous’ variant of unicystic ameloblastoma occurs in older individuals as compared to the ‘dentigerous’ variant.…”

“…It is often accompanied by an innocuous epithelium of varying histological appearance that may mimic the lining of a dentigerous or radicular cyst. 6 Ackermann 3 classified this entity into the following three histological groups:…”

“…The mean age for unilocular, impaction-associated unicystic ameloblastomas is 22 years, whereas the mean age for the multilocular lesion unrelated to an impacted tooth is 33 years. 6 Clinically, lesions are often asymptomatic, and usually cause a painless swelling of the jaws. On radiographic examination, as implied by the term 'unicystic', the common presentation is a unilocular radiolucency; however, occasionally a multilocular appearance may also be observed.…”

Mural Unicystic Ameloblastoma mimicking Odontogenic Cyst

“…It represents 10%–15% of ameloblastomas[ 2 ] and manifests commonly from 11 to 30 years of age with equal gender predilection. [ 2 ] Majority of the lesions are associated with an impacted tooth (dentigerous type) and others are non-dentigerous type. Smaller lesions are asymptomatic while larger lesions result in facial asymmetry and in some cases ulceration of the overlying mucosa.…”

“…[ 1 ] UA was categorized as a separate group by Martinez and Robinson. [ 2 ] The lesion UA arises from reduced enamel epithelium or a dentigerous cyst or from solid ameloblastomas that undergo cystic degeneration. [ 3 ] UA was grouped by Philipsen and Reichart as luminal (subgroup 1); luminal and intraluminal (subgroup 1.2.…”