I asked my oral surgeon's nurse where the bone graft material came from just before it was done. She told me it was irradiated bone material from cadavers, that was obtained from a reputable company that they have used for years (not some fly-by-night unreputable cadaver bone source!
). Chicken that I am, I was just relieved that I wouldn't have to have surgery to move it from elsewhere in my body!
I agree that the hardest part of getting an implant is that it takes so many months to complete it. You have to wait for the bone graft to "take", and for your own bone to grow around the implant or some such thing. The cost sounds worse than it was (even though my insurance didn't cover any of it), because it is spread out over almost a whole year. For me it was $435 for the bone graft and $13.49 for various prescriptions required, both in Dec 2012; $1800 for the implant in April 2013; and then $1200 for the crown in September 2013.
I am wildly enthusiastic about my implant. It is better than the natural tooth ever was, and feels completely natural. It's so good that it's like something out of science fiction. I would highly recommend one to anyone, but be prepared for the wait. It seems like forever before you are done with it.