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, neck stretching and teeth filing. Buddhism has no specific teaching on this matter but other than tattooing, none of these things have ever been practiced 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.
However, for those who desire tattoos 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.