Unlike some other popular spots for piercings, the tongue is full of nerves and blood vessels. This danger makes it a very tricky spot to pierce without damage—and a very hard location to maintain a piercing. In addition to a high risk of damage to the tongue itself, the stud can also cause significant problems for the teeth and gums. Medical professionals like to say that if parents and teens were more acutely aware of what a tongue piercing procedure involves, there would be a lot fewer of them! That stud can be replaced after a few weeks, but even a smaller stud can cause oral health problems. Because the tongue is such a sensitive area and full of blood vessels, the risk of disease transmission is higher than with piercings in some other areas. Tongue piercings have been linked to hepatitis, herpes, tetanus and even tuberculosis. The mouth is a breeding ground for bacteria—which usually cause little or no problems, thanks to protection from saliva and other safeguards. But, the introduction of a foreign object, like a tongue piercing, can cause a bacterial infection near the piercing site—or worse.
Piercings Interfere with Normal Oral Function
Oral piercing of the tongue, lip and cheek may be trendy among teenagers, but the side effects can be dangerous to their teeth and mouth. Many teenagers or young adults do not take the time to learn about the risks associated with oral piercings. Infections from tongue piercings are common because the tongue is covered with bacteria. Your mouth contains millions of bacteria, and infection and swelling often occur with mouth piercings. For instance, your mouth and tongue could swell so much that you close off your airway or you could possibly choke if part of the jewelry breaks off in your mouth. The moment the tongue is punctured, these bacteria may be introduced into the blood. Dentists are learning that oral infections can lead to infections in other parts of the body as well.
With the rise of oral piercings, many teens are piercing their tongues and lips to enjoy a fashion trend. But, an oral piercing can present real danger to the mouth, tongue and teeth of its owner. In addition to tooth damage, those with oral piercings have a greater risk of suffering nerve damage, oral infection, pain and swelling.
Her response to your fear that she might be labeled negatively because of this piercing could be that you have taught her not to let the superficial, baseless stereotyping of others carry any weight with her. She may want to pierce her tongue partly because her "hip mom" has a pierced navel, but I doubt that is her major reason. Notice she is piercing her tongue, a more blatant move than navel piercing, which people do not usually observe in everyday life. I don't think she wants you both to be twins in this regard. I would calmly make your arguments against the tongue piercing, being careful not to shame or blame her as you explain your disapproval. Have a discussion -- don't lecture her. Then, if you feel that she has argued reasonably for why she could safely have her tongue pierced, you must decide whether supporting this or attempting to forbid it will be in your daughter's best interests and in the best interests of your relationship with her.