VACUOLATED CELLS AND MUCOUS METAPLASIA IN THE EPITHELIAL LININGS OF RADICULAR AND RESIDUAL CYSTS

The purpose of this study was to determine whether a consistent associ ation exists between mucous cells and clear or vacuolated cells in the epithelial lining of radicular and residual cysts and to consider whe ther the vacuolated cells may represent a stage in the histogenesis of mucous metaplasia in these linings. Single sections from each of 154 mandibular radicular and residual cysts were stained with periodic aci d-Schiff (PAS) after diastase digestion. Fifteen cases which showed mu cous metaplasia were included in the study and were examined for the p resence of vacuolated cells associated with the mucous cells. Mucous c ells were present singly or in groups within all layers of the stratif ied squamous epithelial lining except the basal cell layer. In nearly all instances small to large ovoid vacuolated cells were found closely associated with the mucous cells. Occasional vacuolated cells contain ed sparse mucin granules or a delicate network of PAS-positive, diasta se-resistant material. It is suggested that the clear cells may repres ent a stage in the histogenesis of mucous metaplasia.