Imaam al-Nawawi (may Allaah have mercy on him) said: “The woman who tattoos is one who uses a needle or similar implement to prick the skin of the hand, wrist, lips or other part of a woman’s body until she draws blood, then she puts dye into the wound. It is haraam to do this or have it done by choice. Similarly, plucking or removing hair from the face is also haraam, whether one does it or asks someone else to do it for one, unless a woman has a beard or moustache, in which case it is not haraam to remove it. Widening the gap between the teeth is done by filing between the incisors. This is done by old women to give the appearance of youth and make the teeth look beautiful, because this attractive gap between the teeth is characteristic of young girls. When a woman gets old, her teeth get big and look ugly, so she may file them to make them look more attractive and give the impression that she is younger… It is haraam to do this or have it done by another, because of this hadeeth, and because it involves changing what Allaah has created, and is a form of deception and falsehood. Widening the gap between the teeth is something that is done to make a person look beautiful, which indicates that what is haraam is when this is done in the pursuit of beauty, but if it were done as a form of treatment because of some problem or deformity in the teeth, then there is nothing wrong with it. And Allaah knows best.” (al-Nawawi, commentary on Saheeh Muslim, 13/107).