Giant recurrent aneurysmal bone cyst of the mandible
A 19 year old male patient presented with a swelling involving left side of the lower face for more than 6 months []. The swelling had rapidly grown in last 2 months and was also associated with pain at the left mandibular angle region. Patient had visited a dental surgeon for the above complaint 4 months back following which he underwent an intraoral procedure with extraction of his left lower third molar tooth under general anesthesia. One month after the procedure the swelling did not resolve and began to increase in size and was associated with pain. On examination there were no extraoral or intraoral draining sinuses or suppuration and patient was in good health with no medical problems except for the pain and swelling which extended from left angle region to the premolar-canine region []. The lesion was firm on palpation, slightly tender. The skin over the swelling was normal.\nIntraorally, the buccal vestibule was obliterated due to the expansion of the buccal cortical plate extending from the retro-molar region to the premolar-canine region. Overlying mucosa was pink and smooth. The teeth were not mobile.\nPanoramic radiograph showed a lytic and expansive lesion showing a ‘honeycomb’ and soap bubble like appearance with defined margins []. Lytic lesion measured 7 cm × 5 cm in its greatest dimension with destruction of buccal and lingual cortical plates but maintaining continuity of the lower border.\nAn incisional biopsy under local anesthesia was carried out and was suggestive of aneurysmal bone cyst.\nSurgical treatment for resection of the mandible followed by immediate reconstruction with a vascularised fibula flap was planned as we concluded it to be a recurrence. Under general anesthesia, through an extraoral submandibular approach the tumor was exposed. The mandible was resected 1 cm beyond the radiographic margins both at the ramus and the premolar-canine regions []. The jaw cortex was ballooned out and thinned having an egg shell appearance, but without loss of continuity. There was infiltration into the soft tissues at areas of perforation of the buccal cortex, which was cleared. Primary reconstruction of the defect was carried out with a vascularised fibula flap [Figures and ] harvested from the right leg and secured with a titanium reconstruction plate []. There was no significant blood loss during surgery. Patient was put on intermaxillary fixation for three weeks.\nThe histopathological examination of the surgical specimen revealed capsule of a cystic lesion with many dilated blood filled cavernous spaces and extravasated RBCs. These spaces were separated by fibrous septa with osteoid tissues, multinucleated giant cells and macrophages []. The diagnosis of an aneurysmal bone cyst was made.\nThe patient had a good postoperative recovery, with good healing. He was on constant follow up for 12 months without any signs of local recurrence. Patient is yet to be dentally rehabilitated on the affected site.