PRIYAMBADA KARNA

and 3 more

IntroductionAmeloblastic fibroma (AF) is a rare, benign odontogenic tumor, accounting for approximately 1.5% to 4.5% of all odontogenic tumors. It was first described by Krause in 1891, but it was later recognized as a distinct entity by Thoma and Goldman in 1946.1 It is more commonly seen in children and adolescents, especially within the first two decades of life. There is a slight predilection for males,2 and the posterior mandible is the most frequent site of involvement. It is often associated with impacted or unerupted teeth.3Clinically, AF typically presents as a slow-growing, painless swelling, which may remain undetected until incidental discovery during routine radiographic examination. Radiographically, it often appears as a well-defined, unilocular or multilocular radiolucent lesion often with sclerotic radiopaque borders.1 Although considered benign, AF has the potential for recurrence and, in rare instances, malignant transformation into ameloblastic fibrosarcoma, emphasizing the importance of early diagnosis and appropriate management.Histopathologically, ameloblastic fibroma consists of both epithelial and connective tissue components. The epithelial component shows proliferating islands, cords, and strands of odontogenic epithelium with a peripheral layer of cuboidal or columnar cells and a central area resembling the stellate reticulum. The connective tissue component, resembling dental papilla, contains spindle and angular cells within a myxomatous stroma of delicate collagen. 2,3 Treatment options typically involve enucleation and curettage, surgical excision, partial resection and reconstruction. This case report discusses a rare presentation of ameloblastic fibroma in an 8-year-old female child, who presented with a painless swelling in the right posterior region of the mandible, which was histologically characterized by dentinoid formation.

SANDHYA CHAURASIA

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IntroductionOdontogenesis is governed by a series of intricate molecular interactions, and any disruption in these processes can lead to neoplasms specific to the jaws, known as odontogenic tumors. Because these tumors originate from various components of the tooth - forming apparatus, they typically exhibit significant histopathological diversity.1In the 5th edition of the WHO classification of odontogenic tumors and cysts of the jaws (2022), a new entity called adenoid ameloblastoma has been introduced under the category of benign epithelial odontogenic tumors, marking a significant update in the classification of odontogenic lesions.2 This tumor is rare, with fewer than 50 cases reported in the literature to date.3 The term ”adenoid ameloblastoma with dentinoid” was first introduced by Branon in 1994. The use of the term ”ameloblastoma” reflects the presence of ameloblast - like cells, alongside stellate reticulum - like cells, which shows positive expression for calretinin, indicating neoplastic ameloblastic epithelium. In adenoid ameloblastoma, the ameloblast-like cells do not express BRAF p.V600E, which is typically found in conventional ameloblastoma. This lack of BRAF mutation raises questions about their relationship, leading to the classification of adenoid ameloblastoma as a distinct entity under benign epithelial odontogenic tumors.4 Historically, various terms have been used to describe similar histopathological features, including atypical plexiform ameloblastoma with dentinoid, 5 hybrid ameloblastoma and adenomatoid odontogenic tumor, 6 and adenomatoid odontogenic tumor originating in unicystic ameloblastoma.7Adenoid ameloblastoma, typically observed in the 4th decade of life, shows a slight predilection for females. It can occur at various sites without a specific predilection. Clinically, it generally presents as a painless swelling.8 Radiographically, the majority of these tumors appear as unilocular radiolucencies, though occasional foci of radiopaque areas may also be present. 9 The key histopathological criteria for diagnosing adenoid ameloblastoma include the presence of ameloblastoma-like components, duct-like structures, morules, and cribriform architectures. Additionally, clear cells, eosinophilic dentinoid material, and focal areas of ghost cell keratinization may also be observed. 2 Differential diagnoses for this tumor include aggressive adenomatoid odontogenic tumor, clear cell odontogenic carcinoma, odontogenic carcinoma with dentinoid, ameloblastic carcinoma, adenomatoid odontogenic tumor with inductive changes, and various histopathological subtypes of ameloblastoma. 2, 10 Treatment options typically involve surgical excision, enucleation, and sometimes radiotherapy.1