There are various types of bone grafts. all are designed to build up the bone that is missing. The type of graft, and the material used would be determined by your dentist.
1.Ridge or socket preservation graft. This type of graft does not mean you have inadequate jawbone for an implant. This type of graft is used to fill in the hole from an extraction site. When an extraction leaves a hole bigger than an implant, it has to be filled in, so there is no vacancy around the implant, which would cause it to fail.
2.Sinus lift. Sometimes the patient has suffered too much bone loss for an implant to be placed without building up the bone. A sinus lift is used in smaller areas of a few teeth, in the upper jaw, below the sinus cavity.
3.Sinus graft & block grafts. When there is a lot of bone loss in the sinus area, front of the mouth, and even in the lower jawline, the bone can be replaced with this type of graft. A block of bone material, which can be either artificial bone, cadaver bone, or bovine bone, is screwed into place with small titanium screws. After the bone has healed and integrated into the natural bone, it serves well to hold implants.