In an attempt to clarify whether the so-called "giant-cell fibroma" is a separate entity among fibrous hyperplasia and tumors, 1550 oral fibrous hyperplasias were reviewed for the presence of stellate and multinucleated cells. In 5% of the lesions stellate and multinucleated cells were a dominant feature of the histologic picture. A surprisingly high number of hyperplasias of the tuberosities (gingival fibromatoses) were found to contain the characteristic cells (31%). On the basis of the varying nature of the lesions and the range of ages at which the stellate and multinucleated cells are found, these lesions should not be regarded as neoplastic in nature or as belonging to a separate entity. Furthermore, based on differences in fiber pattern and localization of the characteristic cells, it is suggested that the stellate and multinucleated cells are active cells, possibly involved in the synthesis of collagen and/or ground substance.