Unveiling a Rare Association: Aneurysmal Cyst and Fibrous Dysplasia of the Mandible - A Case Report

Introduction: Aneurysmal bone cyst (ABC) is a rare benign bone lesion, especially in the craniofacial region. Fibrous dysplasia (FD) is a benign skeletal disorder characterized by the replacement of normal bone with fibro-osseous tissue. The coexistence of ABC and FD in the mandible is extremely rare, with few cases reported in the literature. Case Report: We report the case of a 25-year-old patient with a history of fibrous dysplasia of the right mandible who presented with a painful swelling in the parasymphyseal region. Imaging revealed a multilocular cystic lesion in the right mandible extending from the first premolar to the third molar. Surgical enucleation of the cyst and resection of the involved teeth were performed. Histopathological examination confirmed the diagnosis of fibrous dysplasia with secondary aneurysmal bone cyst. Postoperative recovery was uneventful, except for transient hypoesthesia of the inferior alveolar nerve, which resolved after 11 months. Discussion: The association of ABC and FD is extremely rare, with fewer than 30 reported cases in the literature. This case highlights the importance of early diagnosis and appropriate surgical management to prevent complications and ensure optimal outcomes. The combined approach of enucleation and careful resection allowed for successful treatment, with histological confirmation of both conditions. Conclusion: This case emphasizes the need for awareness of rare associations between benign bone pathologies such as ABC and FD. A multidisciplinary approach, including radiological and histological evaluations, is crucial for accurate diagnosis and appropriate treatment.