Surgery of the temporomandibular joint is indicated for different clinical situations, including internal derangements, hipomobility, hipermobility, pathology and trauma. Mandibular dislocation is an acute painful condition that causes severe functional limitation. Manual reduction, with or without pharmacological assistance, is the treatment of choice and should be performed as early as possible. On rare situations mandibular dislocation may not be perceived by the patient and remain undiagnosed or misdiagnosed for a long period. This may include severe illness, neurological diseases and prolonged intensive care hospitalization with oral intubation and sedation. Treatment of prolonged mandibular dislocation is different. Morphological changes of the joint and associated structures will prevent successful manual reduction even with the patient under general anesthesia. Basically, two types of surgery may be indicated: elimination of the articular eminence (eminectomy) or reestablishment of a new condyle - ramus relationship, that can be achieved by condilotomy. This article reports a case of prolonged mandibular dislocation that was treated surgically with success. A review of the literature is performed by authors and advantages and disadvantages of each type of treatment are discussed.