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Aneurysmal Bone Cyst<-may cause enlargement of affected bone. Sometimes contain cartilage like-matrix.
Aneurysmal bone cyst of the mandible: A case report and review of literature
“Aneurysmal bone cyst (ABC) is rare benign lesions of bone which are infrequent in craniofacial skeleton. ABC’s are characterized by rapid growth pattern with resultant bony expansion and facial asymmetry. We describe a case of ABC in a 25 year old male patient affecting the body of the mandible with expansion and thinning of the buccal and lingual cortical plates. Treatment consisted of surgical curettage of the lesion. A one year follow- up showed restoration of facial symmetry and complete healing of the involved site.”
“ABC is a benign cystic lesion of bone, composed of blood-filled spaces separated by connective tissue septa containing fibroblasts, osteoclast-type giant cells and reactive woven bone”
Spontaneous healing of aneurysmal bone cysts. A report of three cases.
” We report three cases of spontaneous healing of aneurysmal bone cysts (ABC). In one case histological material was obtained after resection of the already ossified expansile mass discovered as a lytic lesion seven months previously. In the two other patients, spontaneous ossification of a radiologically presumed ABC in the lytic and expansile phase was observed after nine and seven months respectively. The healed lesions have remained stable at 12, 32, and 36 months respectively. These findings suggest that when the diagnosis can be made with confidence, and the lesion is in a location and at a stage that does not entail any risk of fracture or compression, expectant management should be considered. Our three patients were aged 22, 19 and 18 years, older than usual for developing ABC. This is also true for many of the few other reported cases of spontaneous or almost spontaneous healing and suggests that ABC has a greater tendency to stabilise in older patients.”
If you look at the results the bone expansion seems to be permanent.