Weed out the Unwanted: Endosurgical Management of a Foreign Body with Cystic Lesion

Aneurysmal bone cysts (ABCs) are expanding osteolytic lesions rarely found in the maxilla. They usually occur after trauma or alterations in local hemodynamics. Secondary ABCs can occur due to vascular changes and inflammation caused by existing periapical infection. A 25-year-old male patient reported with the chief complaint of recurrent swelling and pus discharge in his upper front tooth region for 3 months. He gave a history of trauma 16 years ago. He had undergone root canal treatment in his upper front tooth 4 years ago. Preoperative radiograph and cone-beam computed tomography showed the presence of a large periapical radiolucency and an unusual radio-opaque foreign body. Endodontic therapy was initiated, and a 5 mm mineral trioxide aggregate plug was given. Thorough periapical curettage was done. Histopathological analysis gave a diagnosis of ABC, and scanning electron microscopy analysis identified the foreign body as zinc oxide cement. Follow-up examination showed distinct radiographic healing with a decrease in the size of the lesion. Accurate diagnosis, achieved through a combination of radiographs and histopathology, is crucial for ensuring complete lesion removal and reducing the risk of recurrence.