The nasolabial folds, commonly known as "smile lines"[1] or "laugh lines",[2][self-published source] are facial features. They are the two skin folds that run from each side of the nose to the corners of the mouth. They are defined by facial structures that support the buccal fat pad.[3] They separate the cheeks from the upper lip. The term derives from Latinnasus for "nose" and labium for "lip". Other people suggest the term melolabial fold,[clarification needed][4] or even the lip-cheek fold or groove.[5] It is also known as the nasolabial sulcus.
Cosmetology issues
With ageing the fold may grow in length and depth.[6]Dermal fillings may be used to replace lost fats and collagen in this facial area.[7] Facial exercises give effective results in erasing the appearance of nasolabial folds.[8]
^Burgess, Cheryl M., ed. (2005). Cosmetic Dermatology. Berlin, Heidelberg: Springer-Verlag Berlin Heidelberg. p. 106. ISBN9783540273332. Retrieved 20 February 2015.