Dr. Mike,
Well THAT certainly clears things up! Just kidding, but I had a little trouble at first with "vestibuloplasty". Not sure if I've totally figured out what it is, but at least I've figured out how to say it.

When I pull out my lower lip at the center, the floor of my mouth, the bone, and the lip/facial tissue all pretty much meet at the same spot - at the top of my chin bone. Like if you pinch the very tip of your chin - the top of that bone, or very nearly. Anyway, it's pretty low. The lip cord you mention - I don't think I have one anymore. Makes me wonder how on earth the cutting further down would be accomplished, and would I be wearing dentures on my chin bone?
I guess I'll just hope for implants. If the Docs at Shands say it's the only or best way, then Medicare should approve it, I think, and it sounds a lot easier to deal with afterward, as long as I heal well and my body doesn't reject them or something.
I'll find out on Oct 14th and I'll let you know what they say.
Lani