Keratoacanthoma of the inferior lip: review and report of case with spontaneous regression.

Keratoacanthoma (KA) is a self-limited benign epithelial proliferative lesion that eventually presents with very similar clinical features to squamous cell carcinoma. Many KA appear in the vermilion border of the lips and therefore dental professionals must be familiar of the disease. This article reports the case of a 40-year-old female patient presenting with an exophytic ulcerative tumor in her lower lip that resolved after incisional biopsy.