When you extract teeth, you will lose anywhere from 30 to 60 percent of the bone regeneration if you allow the alveolar bone to grow back on its own. We can improve this with bone grafting.
The amount of bone regeneration will depend on what is left for the body to work with. For bone to regenerate, it needs space, blood, bare bone, and no pressure. If the extraction took place in the mandibular posterior region where the alveolar bone remains thick eighty plus percent of the alveolar bone will probably grow back. You may end up with a slight dip where the extraction took place. Do you need to place bone particles in the socket to encourage bone growth? Probably not. Though, if you are going to place bone in the socket, you need to remove the membrane from the socket. Bone grows back to bone not tissue. If you leave the membrane, then bone will grow beneath the membrane creating a marsupialization situation filling the pocket.
If you extracted a....