Dental Bone Grafting

Bone grafting is a form of transplantation used to replace missing bone tissue or to stimulate new bone formation. In dentistry, its most common purpose is to rebuild jawbone so that dental implants can be placed: implants need enough surrounding bone to support them and to integrate properly, and people who have been without teeth for a long time, or who have lost bone to infection, periodontal disease, trauma or ageing, may not have enough bone in the right places. A graft can be carried out before implant placement or at the same time. The grafted material may be the patient's own bone (autograft), commonly harvested intra-orally from the chin or the ascending ramus of the lower jaw, or from sites such as the iliac crest; donor bone from a bone bank (allograft); animal-derived bone, usually bovine (xenograft); or synthetic material such as hydroxyapatite (alloplast). Xenograft is often chosen for its volume stability over time, while allograft offers strong regeneration but less volume stability, and a mixture of materials is frequently used. Grafts work through osteoconduction (providing a scaffold that guides bone growth), osteoinduction (prompting cells to become bone-forming osteoblasts) and osteogenesis (living bone cells contributing to remodelling). Bone can be placed as a whole block or particulated so that it adapts closely to the defect being repaired.

Most bone grafts are expected to be resorbed and gradually replaced by the patient's own bone as it heals and remodels, a process that typically unfolds over several months rather than days. Where the graft is taken from the patient's own body (an autograft), a second surgical site — such as the chin, the ramus of the lower jaw or the iliac crest — is created, which adds another location for post-operative pain and potential complications. In dental cases the graft may be placed before implants are fitted or at the same time as implant placement, and the implant is added once there is enough healed, stable bone to support it.