Okay, the bumps do appear to be below his hairline. There are spikes up there on the crown though, and he looks young for that much natural hair loss.
As to the implants/surgical grade material. I did ask my wife about it. She said as long as they use materials that have been approved for other implant uses, they don\'t have to be tested for this. (I don\'t know if I mentioned this but my wife is an engineer who reviews implantable medical device applications for the Food and Drug Administration).
So, the material he uses is probably the same stuff they use in various forms of traditional plastic or reconstructive surgery. Knee replacements for example, or chin implants etc. If the material is already approved for implanting then you can put it wherever and in whatever shape you want.
p.s. There was this guy in my highschool who was probably ahead of his time (it being the mid 1980s) and I\'ve never seen anyone else do this: He had an earring connected to a nose ring by a chain. But the chain went from his ear, through a hole in his cheek, out the corner of his mouth to his nose.