Ameloblastoma is a benign epithelial odontogenic neoplasm characterized by locally aggressive behavior. This lesion is often asymptomatic, and some cases are detected during routine radiographic examination. A 33-year-old female patient undergoing orthodontic treatment presented with a 1-month history of a painful swelling in the posterior mandible. Her medical history was noncontributory. Panoramic radiograph showed a well-defined, multilocular radiolucency on the left side of the mandible extending from tooth #37 to the mandibular ramus. A panoramic radiograph obtained for orthodontic documentation 7 years earlier revealed a well-defined, unilocular radiolucency associated with the crown of unerupted tooth #38. Under the diagnostic hypothesis of odontogenic keratocyst, an incisional biopsy was performed. Histopathologic findings confirmed the diagnosis of ameloblastoma. The patient was referred for surgical treatment and remains under close follow-up. This case emphasizes the importance of a detailed analysis of patient images, irrespective of the diagnostic goal, before any dental treatment planning. Ameloblastoma is a benign epithelial odontogenic neoplasm characterized by locally aggressive behavior. This lesion is often asymptomatic, and some cases are detected during routine radiographic examination. A 33-year-old female patient undergoing orthodontic treatment presented with a 1-month history of a painful swelling in the posterior mandible. Her medical history was noncontributory. Panoramic radiograph showed a well-defined, multilocular radiolucency on the left side of the mandible extending from tooth #37 to the mandibular ramus. A panoramic radiograph obtained for orthodontic documentation 7 years earlier revealed a well-defined, unilocular radiolucency associated with the crown of unerupted tooth #38. Under the diagnostic hypothesis of odontogenic keratocyst, an incisional biopsy was performed. Histopathologic findings confirmed the diagnosis of ameloblastoma. The patient was referred for surgical treatment and remains under close follow-up. This case emphasizes the importance of a detailed analysis of patient images, irrespective of the diagnostic goal, before any dental treatment planning.