Oral candidiasis (thrush) is distinguished by its creamy-white plaques that can be scraped off, leaving an erythematous base, whereas leukoplakia is an adherent white plaque.
Morsicatio buccarum presents as a shaggy, white, macerated line along the occlusal plane of the buccal mucosa, corresponding to the bite line.
Reticular oral lichen planus is distinguished by its characteristic lacy, white, networked pattern (Wickham's striae), whereas leukoplakia is a more uniform, homogenous white patch.