Solitary bone cyst / Unicameral Bone Cyst / Simple bone cyst of Jaw

November 17, 2012 | By | Reply More

Solitary bone cyst / Unicameral Bone Cyst / Simple bone cyst of Jaw

A variety of terms have been used to designate this lesion, including simple bone cyst, traumatic bone cyst, haemorrhagic bone cyst, and unicameral bone cyst.

Clinical features

  • The solitary bone cyst occurs predominantly in children and adolescents with a peak incidence in the second decade.
  • There is no definite sex predilection although some series have shown a slightly higher incidence in males.
  • The cyst arises most frequently in the premolar and molar regions of the mandible. Maxillary lesions are rare.
  • The majority of solitary bone cysts are asymptomatic and are chance radiographic findings; some degree of bony expansion occurs in about 25 per cent of cases.

Radiographic features

  • The lesion presents as a radiolucency of variable size and irregular outline.
  • Scalloping is a prominent feature particularly around and between the roots of standing teeth (Fig.).
  • The margins of the lesion are usually well defined.



Pathological features and pathogenesis

Surgical exploration is undertaken to confirm the clinical diagnosis and characteristically reveals a rough bony walled cavity devoid of any detectable soft-tissue lining. In many cases the cavity appears empty, but in others there is a little clear or blood-stained fluid. Rapid healing follows surgical exploration but even without surgical intervention the cyst will resolve spontaneously with time.

Microscopic examination of curettings from the lesion shows that the bony walls are covered by a delicate layer of loose, vascular fibrous tissue (Fig.) containing extravasated red blood cells and deposits of haemosiderin pigment. There is no epithelial lining.

The pathogenesis of the solitary bone cyst is unknown. It is commonly believed that there is a relationship to trauma, but the evidence is not convincing. Although a history of trauma can be elicited in about 50 per cent of cases, the interval between trauma and discovery of the lesion can range from months to years and the apparent relationship may be purely fortuitous. It has been suggested that the solitary bone cyst, aneurysmal bone cyst, and central giant cell granuloma of bone are related lesions reflecting some haemodynamic disturbance in medullary bone. In the case of the solitary bone cyst it has been argued that trauma produces intramedullary haemorrhage which, for unknown reasons, fails to organize and that cavitation occurs by subsequent haemolysis and resorption of the clot.

Tags: , , , , , , , , , ,

Category: Dental, Oral Pathology

WARNING: Any unauthorised use or reproduction of content for commercial or any purposes is strictly prohibited and constitutes copyright infringement liable to legal action.