|
Medical Definition of Vermilion border
1. The red margin of the upper and lower lip that commences at the exterior edge of the intraoral labial mucosa ("moist line") and extends outward, terminating at the extraoral labial cutaneous junction; a thinly keratinised type of stratified squamous epithelium deeply penetrated by well-vascularised dermal papillae which show through the translucent epidermis to impart the typical red appearance of the lips. Synonym: vermilion zone, vermilion transitional zone. (05 Mar 2000)