Sub-dermal piercing or Single Point piercing?

I believe you are talking about what is called a microdermal implant. It's an offshoot of the subdermal implant that is much less invasive and is supposed to heal much better. Basically it's a small tab of metal wit two or three holes and a post. the tab is inserted under your skin by way of a small incision and the post portrudes slighty above skin level and that's what the jewlery is attched to.

This is considered an advanced procedure and you shouldn't go to your run of the mill piercer for it.

Craspy is right on with his description, I just wanted to add one more thing:

If you decide to get this, remember that it's ment to be permanent, it's not really something you can just decide to take out if you get bored with it. It has to be removed with a scalpel. Your skin grows into the holes and litterally anchors it into your flesh.

Just wanted you to know this. It's not just like a normal piercing.

Also, they're really easy to mantain. Most of the time, you just have to use some sea salt for the first few weeks, then just leave it the hell alone. They're extremely easy to heal assuming youve gone to a quality artist that knows what s/he's doing. regection is a risk, but as long as the piercing doesn't take a direct blow, it usually doesn't happen.

www.bmezine.com has an article and a lot of information on the microdermals. Remember that this is still a fairly new type of piercing and it's still kind of in the testing stage.

Hope I helped!

Hmm, I've never seen those. All I've seen are surface piercings. I don't understand how a piece of jewelry would stay anchored under the skin without surgical procedures?