This is an amazing article, according to one scientist within ten years that we will have strategies that will allow us to re-grow the bones and functional tissue:
"The photos of his severed finger tip are pretty graphic. You can understand why doctors said he'd lost it for good. Today though, you wouldn't know it. Mr Spievak, who is 69 years old, shows off his finger, and it's all there, tissue, nerves, nail, skin, even his finger print. How? Well that's the truly remarkable part. It wasn't a transplant. Mr Spievak re-grew his finger tip. He used a powder - or pixie dust as he sometimes refers to it while telling his story."
Six Million Dollar Man toy photo found via W!L.