Bone grafting is a surgical procedure that replaces the missing bone to repair highly complex bone fractures, poses a significant health risk to the patient, or fails to heal properly. Some types of small or acute fractures can be cured but are at risk for major fractures such as fracture of the compound.
Bones generally have the ability to regenerate completely but require very little fracture space or some sort of scaffolding to do so. Bone grafts can be autologous (bone taken from the patient's own body, often from iliac crest), allograft (cadaveric bone usually obtained from bone), or synthetic (often made of hydroxyapatite or other naturally occurring and biocompatible substances) with mechanical properties bone. Most bone grafts are expected to be absorbed and replaced when the natural bone heals for several months.
The principles involved in successful bone grafting include osteoconduction (guiding the natural reproductive growth of the bone), osteoinduction (pushing undifferentiated cells into active osteoblasts), and osteogenesis (living bone cells in graft materials contribute to bone remodeling). Osteogenesis occurs only with autograft tissue and an allograft cellular bone matrix.
Video Bone grafting
Biological mechanisms
Bone grafting is possible because bone tissue, unlike most other tissues, has the ability to regenerate completely if space is available for growth. When the original bone grows, it will generally replace the complete transplant material, resulting in a completely new integrated bone region. The biological mechanisms that provide a rationale for bone grafting are osteoconduction, osteoinduction and osteogenesis.
Osteoconduction
Osteoconduction occurs when bone graft material serves as a scaffold for new bone growth perpetuated by the original bone. Osteoblasts of the transplanted margins of the defect utilize bone graft materials as a framework for spreading and producing new bone. At the very least, bone graft materials should be osteoconductive.
Osteoinduction
Osteoinduction involves stimulating osteoprogenitor cells to differentiate into osteoblasts which then initiate new bone formation. The most widely investigated type of osteoinductive cell mediator is bone morphogenetic proteins (BMPs). Osteoconductive and osteoinductive bone osteoclasts not only function as scaffolds for current osteoblasts but also trigger the formation of new osteoblasts, which theoretically encourage faster graft integration.
Osteopromotion
Osteopromotion involves increased osteoinduction without osteoinductive property ownership. For example, enamel matrix derivatives have been shown to increase the osteoinductive effect of frozen bone allograft (DFDBA), but will not stimulate new bone growth alone.
Osteogenesis
Osteogenesis occurs when vital osteoblasts derived from bone graft materials contribute to new bone growth along with bone growth produced by two other mechanisms.
Maps Bone grafting
Method
Depending on where bone graft is needed, different physicians may be required to perform surgery. Doctors who perform bone graft procedures are usually orthopedic surgeons, head otolaryngology and neck surgeons, neurosurgeons, craniofacial surgeons, oral and upper jaw surgeons, podiatrist surgeons and periodontologists, dental surgeries, surgeons and experts implantology.
Autograft
Autologous (or autogenous) bone transplantation involves the use of bone obtained from the same individual receiving the grafts. Bones can be harvested from non-essential bones, such as from iliac crest, or more commonly in oral and maxillary surgery, from the mandibular (chin) or anterior mandibular ramus (coronoid process); this is especially true for graft blocks , in which small blocks of bone are placed intact in the transplanted area. When block transplants are performed, autogenous bone is the most preferred because there is less risk of graft rejection because the graft comes from the patient's own body. As shown in the graph above, such transplants will be osteoinductive and osteogenic, and osteoconductive. The negative aspect of an autologous graft is that additional surgical sites are needed, which essentially adds another potential site for pain and post-operative complications.
Autologous bone is usually taken from an intra-oral source as a chin or an extra-oral source as iliac crest, fibula, ribs, mandibles and even the skull.
All bones require a blood supply at the transplant site. Depending on where the transplant location and graft size is, additional blood supply may be required. For this type of graft, the extraction of the periosteum and the accompanying blood vessels along with the donor bone is required. This type of graft is known as a vital bone graft.
Autograft can also be performed without solid bone structure, for example using the re-formed bone of the anterior superior iliac spine. In this case there is osteoinductive and osteogenic action, but no osteoconductive action, because there is no solid bone structure.
Chin offers a large number of cortico-cancellous autograft and easy access among all intraoral sites. These can be easily harvested in office settings under local anesthesia on an outpatient basis. The proximity of the donor and recipient locations reduces the operating time and costs. Convenient surgical access, low morbidity, hospitalized hospitalization, minimal donor site discomfort and skin scar removal are additional benefits.
Dentin graft
Dentin bone, made from extracted teeth, Dentine comprises more than 85% of the tooth structure, enamel consists of HA minerals and consists of 10% tooth structure. Dentin is not like bone in its chemical composition, with 50% volumes of HA minerals and 50% organic matrix, mostly fibrous I collagen type. Dentin, like bone, can release growth and differentiate factors while being absorbed by osteoclasts. To make artificial tooth graft workable and bacteria-free, some companies have developed clinical procedures that include grinding, sorting and dental cleaning for immediate or future use. In Korea, Korea Tooth Bank conducted its own bio-recycling 38,000 patients from January 2009 to October 2012.
Allografts
Allograft bone, like autogenous bone, is derived from humans; the difference is that the allograft is taken from someone other than the one receiving the graft. Allograft bones can be taken from the carcasses that have donated their bones so they can be used for the living people who need them; this is usually sourced from the bone bank. The bone bank also supplies an allograft bone sourced from living human donor bone donors (usually hospitalized patients) who undergo total elective pelvic arthroplasty (total hip replacement surgery). During total hip replacement, the orthopedic surgeon lifts the patient's femoral head, as an essential part of the process of incorporating an artificial hip prosthesis. The femoral head is an area of ​​approximately rounded bone, located at the proximal end of the femur, with a diameter of 45 mm to 56 mm in adult humans. The patient's femoral head is most often discharged into hospital waste at the end of the surgical procedure. However, if a patient meets a number of stringent regulatory criteria, medical and social history, and provides informed consent, their femoral head can be stored in the bone of the hospital.
There are three types of bone allograft available:
- Fresh or fresh frozen bones
- Frozen bone alograft (FDBA)
- Demineralization of dry shins (DFDBA)
Alloplastic graft
An alloplastic graft can be made from hydroxylapatite, a natural mineral that is also a major mineral component of bone. They may be made of bioactive glass. Hydroxylapatite is a Synthetic Bone Graft, the most widely used now among other synthetic osteoconductions, its hardness and its acceptance by bone. Tricalcium phosphate is now used in combination with hydroxylapatite thereby giving effect to both osteoconduction and resorbability. Polymers such as some micropore grades of PMMA and various other acrylates (such as polyhydroxylethylmethacrylate aka PHEMA), coated with calcium hydroxide for adhesion, are also used as alloplastic graft for infection inhibition and mechanical resistance and biocompatibility. Reducing sea algae such as Corallina officinalis has a fluorohidroksyapatitic composition that is structurally similar to human bone and offers a gradual resorption, so it is treated and standardized as "FHA (hydroxy-apatitic) biomaterial" alloplastic bone graft.
Synthetic variant
Artificial bone can be made from ceramics such as calcium phosphate (eg hydroxyapatite and tricalcium phosphate), Bioglass and calcium sulphate; all of which are biologically active for different degrees depending on the solubility in the physiological environment. These materials can be doped with growth factors, ions such as strontium or mixed with bone marrow aspiration to enhance biological activity. Some authors believe this method is lower than autogenous bone grafting but infection and grafting rejection are far less than risk, and mechanical properties such as Young's modulus are proportional to bone. The presence of such elements as strontium can produce higher bone mineral density and increase in vivo osteoblast proliferation.
Spacer while
Synthetic materials can be used as temporary antibiotic spacers before being replaced by more permanent materials. For example, the Masquelet procedure initially consisted of using PMMA mixed with antibiotics (vancomycin or gentamicin) for 4-12 weeks, and then replacing the space with an autologous bone graft. Can be used to treat bone deformities post trauma.
Xenografts
Xenograft bone replacements are derived from other species other than humans, such as cow bone (or recent pork bone) that can be frozen dried or demineralized and depotinized. Xenografts are usually only distributed as calcification matrices. The coral species of Madrepore and or millepore are harvested and treated into 'coral granules' (CDG) and other types of coralin xenografts. Coral-based coral Xenografts, especially calcium carbonate (and an important proportion of fluoride, are useful in the context of transplantation to enhance bone development) while natural human bone is made of hydroxyapatite along with calcium phosphate and carbonate: the coral material is thus both industrialized to hydroxyapatite via a hydrothermal process, produce non-resorbable xenografts, or simply the process is removed and the coralline material remains in a state of calcium carbonate for better resorption of the graft by natural bone. Xenograft coral is then saturated with gel and growth-enhancing solution.
Growth Factors
Improved graft growth factors are produced using recombinant DNA technology. They consist of Human Growth Factor or Morphogen (Bone Morphogenic Protein in relation to carrier media, such as collagen).
Recovery and maintenance
The time it takes for an individual to recover depends on the severity of the injury treated and lasts anywhere from two weeks to two months, with the possibility of strenuous exercise prohibited for up to six months.
Usage
Dental implants
The most common use of bone grafting is in the application of dental implants to restore lost tooth area. Dental implants require bone underneath for proper support and integration into the mouth. As mentioned earlier bone graft comes in various forms such as autologous (from the same person), Allograft, Xenograft (especially cow bones), and Alloplastic materials. Bone graft can be used before implant placement or simultaneously. People who have been tense (without teeth) for long periods may not have enough bone left in the required location. In this case, the bone can be taken from the chin, from the pilot's hole to the implant, or even from the iliac crest from the pelvis and inserted into the mouth under the new implant.
In general, bone graft is either used en block (such as from the chin or ramus rising area of ​​the lower jaw) or particulate, in order to better adapt to defects.
Dental bone grafting is a special oral surgical procedure that has been developed to rebuild the missing jaw bone. This loss can be caused by a dental infection in an abscess, periodontal disease, or trauma. There are various reasons for replacing lost bone tissue and promoting natural bone growth, and each technique treats jaw bone defects differently. The reasons that bone grafting may be needed include sinus enlargement, socket preservation, ridge enlargement, or regeneration.
Fiber shaft
Other common bone spurs, which are more important than those used for dental implants, are from the fibular stem. After segments of the fibular stem have been removed normal activities such as running and jumping are allowed on the foot with bone deficits. The grafted grafts have been used to restore skeletal integrity to the long bones of the limbs where congenital bone defects exist and replace bone segments after trauma or malignant tumor invasion. Periosteum and nutrient arteries are generally removed with bone fragments so that the grafts will remain alive and grow when transplanted to a new host site. Once the transplanted bone is secured to its new location it generally returns the blood supply to the bone where it has been attached.
More
In addition to the primary use of bone implants - dental implants - this procedure is used to integrate joints to prevent movement, repair broken bones, and repair broken bones that have not healed.
Bone graft is used in the hope that damaged bones will be cured or will grow back with little or no graft rejection.
Risk
As with any procedure, there are risks involved; This includes reactions to medications, respiratory problems, bleeding, and infections. Infection is reported to occur in less than 1% of cases and can be cured with antibiotics. Overall, patients with pre-existing diseases have a higher risk of infection than those who are healthy overall.
Risk for grafting of iliac crest
Some of the potential risks and complications of bone grafts using iliac crest as a donor site include:
- obtained bowel herniation (this is a risk for larger donor sites (& gt; 4cm)). About 20 cases have been reported in the literature from 1945 to 1989 and only a few hundred cases have been reported worldwide
- meralgia paresthetica (an injury to the lateral femoral cutaneous nerve also called Bernhardt-Roth syndrome)
- pelvic instability Fracture
- (very rare and usually with other factors)
- injury to the caudial nerve (this will cause the posterior pelvic pain worsened by sitting)
- injury to the ilioinguinal nerve
- infection
- minor hematoma (common occurrence)
- deep hematoma requiring surgical intervention
- seroma
- ureter injury
- pseudoaneurysm iliac artery (rare)
- tumor transplant
- cosmetic defects (mainly caused by not preserving superior pelvic bone)
- chronic pain
Bone grafts harvested from the posterior iliac crest generally have less morbidity, but depending on the type of surgery, may require a flip when the patient is under general anesthesia.
Cost
The bone graft procedure consists of more than just the surgery itself. Total total cost for 3 months from a complementary complementary postterolateral fusion bone fusion recovery with graft extensions ranged from an average of about $ 33,860 to $ 37,277. This price includes all visits in and out of the hospital for 3 months. In addition to the cost of the bone graft itself (from $ 250 to $ 900) other costs for this procedure include: outpatient rehabilitation costs ($ 5,000 to $ 7,000), screws and rods ($ 7,500), rooms and meals ($ 5,000) ($ 3,500), sterile supplies ($ 1,100), physical therapy ($ 1,000), surgeon fees ($ 3,500 averages), anesthesiologic costs (about $ 350 to $ 400 per hour), medical expenses ($ 1,000 ), and additional fees for services such as medical supplies, diagnostic procedures, equipment using fees, etc.
See also
References
Further reading
-
Desai, AJ; Thomas, R; Tarun Kumar, AB; Mehta, DS (2013). "The current concepts and guidelines in graft chin making: A literature review". International Orthopedic Journal . 3 (1): 16-25. doi: 10.4103/2231-6027.122094.
Source of the article : Wikipedia
0 Comments