良性セメント芽細胞腫の1例

細胞増殖能に関する比較検討

抄録

Benign cementoblastoma, which is classified as a true cementoma by the WHO's histological typing of odontogenic tumours (1992), is contiguous with tooth roots and is characterized by formation of a cement-like tissue sheet containing many reversal lines and unmineralized peripheral areas. To our know ledge, there has been no report about the proliferative activity of cells in this tumor. We studied a benign cementoblastoma arising in the mandibular right first molar of a 20-year-old man and immunohistochemically evaluated the proliferative activity of its cells with the use of proliferating cell nuclear antigen. The positive cell rate of cementoblasts and enclosed cells were 36.2% and 18.5%, respectively. These rates were higher than those of extracted tooth cement (15.0%, 0%), studied as control. This study clearly demonstrated that the tumor cells had high proliferative activity, suggesting that the lesion is a true tumor. The literature of Japan, Europe, and America on this tumor was reviewed. There is considerable predilection with respect to location.