Oral epithelium is missing adnexal skin structures like hair follicles, sweat glands, and sebaceous glands that are associated with outer skin epithelium. Other differences between oral and outer skin epithelium include color, a moist surface, minor salivary glands in the oral mucosa, smooth texture with some exceptions, and varying firmness of the oral mucosa.

1. what additional component associated with outer skin epithelium is not seen in oral epithelium
Solution
the missing components in oral epithelium are adnexal skin structures such as hair follicles,
sweat glands
and sebaceous glands.
other differences include:
color, moist surface, presence of minor salivary glands in oral mucosa, smooth texture of oral
mucosa (with some exceptions), varying firmness of oral mucosa.