Ultrastructure of different clinical forms of oral leukoplakia.

Twelve cases of oral leukoplakia were studied at the light and electron microscopic levels. In clinical leukoplakia simplex and verrucosa, both light and electron microscopic investigations revealed evidence of increased keratinization. Clinically erosive and histiologically dysplastic leukoplakias showed ultrastructural alterations characteristic of oral carcinomas in some instances.