An Extrafollicular Adenomatoid Odontogenic Tumor Mimicking a Periapical Cyst

Abstract

Adenomatoid odontogenic tumor (AOT) is a rare noninvasive odontogenic tumor that occurs mostly in the second decade of life. Based on its tooth association, AOT can be classified into three categories of follicular, extrafollicular, and peripheral types; the follicular classification is considered as the most common type of AOT. This study reported a large extrafollicular case of AOT in a 40-year-old female. She was asymptomatic and tumor was detected accidentally by her dental practitioner. Since the panoramic radiograph showed a well-defined unilocular radiolucent lesion, we observed radiopaque spots within the lesion by using cone beam computed tomography. The extrafollicular type can mimic a periapical radiolucent lesion.

Adenomatoid odontogenic tumour in the anterior mandible: a case report

“…Subsequently, 67.9% of all cases involve a canine of which 40-83.3% and a global average of 66% involve the maxillary canine. The anterior maxilla is affected in 40-83.3% of reported cases with a global average of 66% 6,7,12,14,16,[18][19][20][21]29 . Lesions in the mandible attribute to 27-54.8% of occurrences and globally 38.2% of which the anterior segments are affected in 28-58% of cases 12,14,16,18,21 .…”

“…Intraosseous lesions consist of up to 97% of all AOTs 10,12,19 . With the majority of these the follicular type known to be from 65% to 97.2% 6,16,21 with a global average from 70% to 73% 7,8,11,[18][19][20] . The extrafollicular type attributes from 24.3% to 27% 6,8,12,20 and the rare peripheral lesion is seen in 2.3-5% of the total reported cases 6,8,[10][11][12]18,20 .…”

“…Tooth displacement with jaw expansion may be observed. The predilection for the mandible, lesions crossing the midline, cortical bone perforation, root resorption, ill-defined borders and the extrafollicular type is thought to be less common and has been associated with older patients 2,[6][7][8]18 . The average reported AOT size ranges from 1 to 3 cm 1,8,18 , but can range from 0.4 to 12 cm, with a mean of 2.9 cm 8,12 .…”

“…Recently, it has been suggested that the lesion may arise from remnants of the dental lamina associated with the gubernacular cord 3,10,15,16 . Conventional presentation, include clinically, a slow-growing asymptomatic intraoral swelling; demographically, occurrence in the second decade of life with females affected more frequently than males (2:1); site, marked predilection for the anterior segments of the jaw, with incidence twice as often in the maxilla; and radiographically, a well-circumscribed homogenous unilocular radiolucent lesion with a sclerotic border 2,3,9,17 rarely exceeding 3 centimetres (cm) in maximum diameter 1,8,18 . Other features include associated tooth displacement and though rare, root resorption.…”

“…The less common extrafollicular type arises in the inter-radicular alveolar bone between the roots of teeth. The rare peripheral extraosseous type occurs on the buccal gingiva 3,9,10,18 . Although the majority present with the common described clinical and radiological features, more lesions with uncommon and extraordinary features are being reported (Table 1) 16,[21][22][23][24][25][26][27][28] .…”