Laugh lines are the vertical lines that extend from the sides of the nose and curve around the mouth and sometimes extend to the chin. You're not the only one that has them—these lines are incredibly common. There are two types of laugh lines: the nasolabial crease and the nasolabial fold. The nasolabial crease is the line you see between the upper lip and cheek and the fold is the skin or tissue that hangs over that crease. Both types develop over time from aging and other lifestyle factors.
If you look back in your high school yearbook, probably half the people have a nasolabial crease—so it is not necessarily a sign of aging. People develop deeper creases with age, weight gain, and with recession of the dentition or dental problems; the teeth are no longer supporting the overlying tissue which makes the crease deeper.
Finding a treatment to reduce their appearance depends on whether they are dynamic wrinkles (wrinkles you see with movement) or static wrinkles (wrinkles you still see when your face doesn’t move). You want to prevent the static wrinkles because they can become more difficult to treat over time. Laugh lines seen when you are laughing are dynamic wrinkles, and when you are not laughing but are still there are considered static. They are pretty common as we use the muscles around our eyes and lips all the time when blinking, smiling, animating, etc.