CULTURE AND ORIGIN OF EPITHELIUM-LIKE AND FIBROBLAST-LIKE CELLS FROM PORCINE PERIODONTAL-LIGAMENT EXPLANTS AND CELL-SUSPENSIONS

A method was developed for preparing cell suspensions from the periodontal ligament of porcine primary molars. Culture of these isolated cells resulted in the growth of 2 morphologically distinct cell populations; epithelium-like and fibroblast-like. The plating efficiency of the cell suspension was estimated at about 0.02%. Similar cell populations were obtained using a simple explant technique. Autoradiographic examination of explants labeled with [H3]-thymidine indicated that DNA-synthesizing cells were 1st detectable between 18-30 h after explantation. The most likely origin of the epithelium-like cells was the epithelial rests of Malassez. Some of the cells of fibroblast-like morphology that incorporated the label at the earliest times appeared to be located in the immediate vicinity of blood vessels. These findings are novel in that growth of cells from dissociated periodontal ligament, elucidation of the origin of monolayers derived from connective tissue cells of periodontal ligament and cell culture of epithelium derived from this source were not previously reported.