Table 3.

World Health Organization cytological features for oral epithelial dysplasia

Cytological features
Group features	Specific features
Nuclear features	Abnormal variation in nuclear size (anisonucleosis)
	Abnormal variation in nuclear shape (nuclear pleomorphism)
	*Increased nuclear size
	Hyperchromatic nuclei
Nucleolar features	Increased number and size of nucleoli
Keratin features	*Single cell keratinization
Mitotic features	Increased mitotic activity
	*Apoptotic mitoses
	Atypical mitotic figures
Cell features	Abnormal variation in cell size
	Abnormal variation in cell shape
	Increased nuclear:cytoplasm ratio

*Denotes new additions to the criteria [10]