Quiste óseo aneurismático

the aneurysmal bone cyst (abc) is a benign and rare lesion in maxillary bones, is more frequent in largo bones of skeletal and spinal column. some authors speculate about that its origin be traumatic, malformation of neoplasm. the radiographic appearance may to show from a diffuse image up to a well defined image very similar to the other maxillary lesions turning wide the differential diagnosis. with destruction of the bon cortex it is possible to create a reaction image of periosteum in sunbeams characteristic of malignant lesion. this is the case of a female patient aged 17 seeking help in the bucco-maxillofacial surgery and traumatology service of the s？o vicente de paulo hospital _ rs, presenting with pain and an increased mandibular volume. she manifested that around one year she began to feel a discomfort next to he right mandibular angle, which was progressively increasing the volume. the radiographic appearance resembled a malignant lesion. after the histopathology verification of abc, treatment choosed for this case was of type conservative surgical with bone cavity curettage and was maintained under systemic postoperative control for 6 and 18 months. in the taken panoramic radiographies is verified the bone neoformation and the cure of case.