The lips are cosmetically very important and are vital for speaking, eating and non-verbal communication. They are formed in part by skin (dry) and mucosa (red and wet). They have a rich blood supply and a complex system of muscles underneath to form many different positions. It is important that the lips should be able to seal completely, otherwise dribbling may result. Small irregularities are readily visible. The upper lip is particularly challenging in this regard because it has subtle curves, hollows and mounds, which may be lost after a repair.