I don't know anything about the removal of implants, but I was told that taking out a root canal was a cake walk to removing an implant. This was one holistic dentist's opinion. so it may not be true. Also this was at least a dozen years ago. This was one reason I didn't want implants. The other was that any metal in the mouth can interupt the connection between the brain, and the body/organs. The Zirconia implants wern't perfected at that time.
Is bone graft still always necessary?
No! I had several amalgams removed as well as a few root canals, but Clear choice [implant specialist] said I only need one bone graft for one tooth. At that time bone graft was to be from a cadaver.