Different cultures or groups within specific cultures sometimes disfigure the human body in ways that are permanent. Some examples of this are foot binding, male and female circumcision, tattooing, scarification, head binding and teeth filing. Buddhism has no specific teaching on this matter but other than tattooing, none of these practices have ever been practised in Buddhist countries. This is probably due to Buddhism’s generally respectful attitude towards the body and its disparagement of superstitions of the type that require disfiguring the flesh. Some religious and secular legal systems advocate amputation or death for certain crimes. Buddhism is against such drastic punishments for two reasons. (1) They involve extreme cruelty which is an evil in itself and they also have a hardening effect on the persons who carry out such punishments and on society in general. (2) All legal systems are human institutions and thus fallible. If a person is mutilated or executed for a crime and it is later discovered that they were actually innocent, it is impossible to justly rehabilitate them.
However, for those who desire body piercing and see it and use it as an art, Buddhism has no specific prohibitions for lay people to engage in such activities. For monastics, there is a higher standard, but there is no 'sin' for lay people to engage in this activity.
- http://www.BuddhismA2Z.com/ Buddhism A to Z. Ven. Dhammika, 2007.