 The traumatic bone cyst TBC is an infrequent nonepithelial lined cavity of the jaws, which was first expressed by lucassin 1929, the lesion has attracted a great deal of interest in the dental literature, but its pathogenesis is still not evidently recognized. It determines a bone cavity of irregular shape which appears like a cyst on a radiograph, and histopathologically there are no elements to confirm a diagnosis of a cysts. TBC the international histological classification assumed by the World Health Organisation for odontogenic tumours utilizes the term solitary bone cyst, nevertheless the term traumatic bone cyst TBC is more extensively used in the literature. The WHO classification explains TBC as a non-neoplastic osseous lesion because it demonstrates no epithelial lining, which differentiates this lesion from the true cysts. There is general conformity that most traumatic bone cysts present without symptoms or signs. Seldom, expansion of the cortical plate may occur with extraoral swelling, less commonly there may erosion through the cortical bone may take place. Teeth in the area of involved bone usually remain vital, without root resorption or tooth mobility. Treatment of traumatic bone cysts has included surgical exploration and curettage to motivate bleeding within the bony cavity, packing of the cyst cavity with Gelfoam which has been saturated with thrombin and penicillin, and bone grafting based on previous study Injection of autogeneic blood into the bony cavity of a traumatic bone cyst was followed by rapid resolution of the lesion. 