Exfoliative cytology and ultrastructure of superficial epithelial cells from the normal human oral mucosa.

Superficial, mature epithelial cells were collected from clinically normal hard palate, cheek and lip of 5 volunteers. These cells were stained using 3 different exfoliative cytology methods and prepared for electron microscopy. In total, 209 individual cells were examined both by the light and electron microscopes and classified as orange, red or blue cells exhibiting an oral keratin or a filament pattern. The combination of data sets revealed that type and degree of terminal differentiation are not related to the staining characteristics. Independent of the staining methods, cells displaying an oral keratin pattern stained either orange, red or blue, and cells displaying a filament pattern stained either red or blue. It is concluded that the staining characteristics of superficial oral epithelial cells do not reflect their status of terminal differentiation as seen ultrastructurally.