Definition: 'Vermilion Zone'
vermilion zoneType: Term
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 keratinized type of stratified squamous epithelium deeply penetrated by well-vascularized dermal papillae which show through the translucent epidermis to impart the typical red appearance of the lips.
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