A clinicopathologic study was made on 30 cases of the traumatic bone cyst of the jaws, and these observations were recorded. --The lesion is one of skeletal-wide distribution, but in the jaws it occurs most frequently in the posterior portions of the mandible. --The majority of cases are not associated with trauma, and the lesion is most commonly detected in routine radiographs. --The median age of this series of patients was 20 years, and the majority of patients in this series white men. --Histologically extravasated red blood cells, degenerating fibromyxomatous tissue both inside and outside of bone, hemorrhagic membranes, and other changes consistent with degenerative processes were observed. --The origin of the traumatic bone cyst was not determined in this study, but histologic evidence pointed toward a degenerative process that also could not be adequately explained; therefore, the more general term solitary bone cyst is suggested for use. --Treatment of the solitary bone cyst consists essentially of exposing the lesion and mild curetting to produce a clot formation that will subsequently organize and fill in with new bone.