Bone grafting

[1] Osteoconduction is termed as "the property of a material to support tissue ingrowth, osteoprogenitor cell growth, and development for bone formation to occur".

[3] The proper bonding of bioactive chemicals (Beta-Tricalcium Phosphate) in implants used in bone grafting surgery allow the promotion of osteoconductivity in the area of a defect.

A negative aspect of autologous grafts is that an additional surgical site is required, in effect adding another potential location for post-operative pain and complications.

[citation needed] An autograft may also be performed without a solid bony structure, for example, using bone reamed from the anterior superior iliac spine.

[citation needed] Chin offers a large amount of cortico-cancellous autograft and easy access among all the intraoral sites.

Convenient surgical access, low morbidity, elimination of hospital stay, minimal donor site discomfort and avoidance of cutaneous scars are the added advantages.

Dentin is similar to bone in its chemical composition, by volume 70–75% is HA mineral and 20% organic matrix, mostly fibrous type I collagen.

In order to make the dentin graft usable and bacteria-free, some companies have developed clinical procedures which include grinding, sorting and cleaning of the teeth for immediate or future use.

However, if a patient satisfies a number of stringent regulatory, medical and social history criteria, and provides informed consent, their femoral head may be deposited in the hospital's bone bank.

Polymers such as some microporous grades of PMMA and various other acrylates (such as polyhydroxylethylmethacrylate aka PHEMA), coated with calcium hydroxide for adhesion, are also used as alloplastic grafts for their inhibition of infection and their mechanical resilience and biocompatibility.

[13] These materials can be doped with growth factors, ions such as strontium[14] or mixed with bone marrow aspirate to increase biological activity.

The presence of elements such as strontium can result in higher bone mineral density and enhanced osteoblast proliferation in vivo.

For example, the Masquelet procedure consists of initially using PMMA mixed with an antibiotic (vancomycin or gentamicin) for 4–12 weeks, and then replacing the space with an autologous bone graft.

Most xenografts are derived from bovine sources such as cows or pigs and are sterilized and processed for safe implantation into human tissue.

[17] Coral based xenografts are mainly calcium carbonate (and an important proportion of fluorides, useful in the context of grafting to promote bone development) while natural human bone is made of hydroxyapatite along with calcium phosphate and carbonate: the coral material is thus either transformed industrially into hydroxyapatite through a hydrothermal process, yielding a non-resorbable xenograft, or simply the process is omitted and the coralline material remains in its calcium carbonate state for better resorption of the graft by the natural bone.

Zoonoses, which are diseases that arise from the crossing of animal and human tissue, pose a threat to the success of xenograft implantation.

They have the potential to create a public health risk if they are not closely monitored, as they can cause diseases to be more easily transmissible through different species.

[citation needed] In general, bone graft is either used en bloc (such as from the chin or the ascending ramus area of the lower jaw) or particulated, in order to be able to adapt it better to a defect.

There is currently some evidence supporting the use of autologous platelet concentrates (cell fragments containing growth factors to promote tissue regeneration) when bone grafting is used to treat gum disease.

After the segment of the fibular shaft has been removed normal activities such as running and jumping are permitted on the leg with the bone deficit.

The periosteum and nutrient artery are generally removed with the piece of bone so that the graft will remain alive and grow when transplanted into the new host site.

[23] Some of the potential risks and complications of bone grafts employing the iliac crest as a donor site include:[23][24][25] Bone grafts harvested from the posterior iliac crest in general have less morbidity, but depending on the type of surgery, may require a flip while the patient is under general anesthesia.

Illustration of an autograft harvested from iliac crest
A bone allograft
Flexible hydrogel-HA composite, which has a mineral-to-organic matrix ratio approximating that of human bone