双唇又名重复唇、二重唇,乃是上唇或下唇增生的一种畸形,表現在唇紅緣以內的粘膜部份,两側呈对称性地增生肥厚,当唇向两側伸展,或作笑容表情时,其皺折更显,好似二唇重迭。双唇以上唇为多,远藤至六郎氏在口腔科通論及手术学一书中仅提到一例43岁女性患者为上唇之双唇,国內連瑞华氏曾报告二例亦为 Lips, also known as repeated lips, double lips, but the upper lip or lower lip hyperplasia of a deformity, manifested lip mucosa within the lip red part of bilateral symmetry hyperplasia hypertrophy, when the lips stretch to both sides, Or make a smile expression, the wrinkle even more, like two lips overlap. Lip more than lip, Endo to six Lange in the Department of Stomatology and Surgery, a book only mentioned a 43-year-old female patient lips lip, the domestic Lian Ruihua has reported two cases