Smile line is called nasolabial fold in medical language. These are the lines located on both sides of the mouth. When a person smiles, these lines are clearly visible. These lines are made of dense bundles of fibrous tissue and muscles. Nasolabial folds are visible in almost everyone except newborn babies, but smile lines are more visible in some people. In fact, as the skin becomes looser and thinner, the smile lines become more clearly visible.In this article you will learn in detail about the symptoms, causes and treatment of smile line -
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