Bone grafts harvested in the iliac crest, rib, or calvaria bring nonvascularized bone grafts. Autogenous bone grafts are more resistant to infection than allogenic grafts. They're usually of excellent quality and provide osteoconductive and osteoinductive properties. The rib can be used for condylar reconstruction and can be shaped according to the requirements.
Iliac bone grafts and calvarial bone grafts can be used to reconstruct alveolar defects or bone defects under 5 cm. The graft is shaped and it is cortex is perforated at multiple sites to enhance vascularity and eventual resorption. While rib grafts have proven ideal for condylar reconstruction, iliac crest grafts are better suited to the maintenance of dental implants.
The development of osteosynthetic plates markedly improved the outcome of mandibular reconstruction. These plates are relatively easy to use, give a firm platform for healing, and are associated with low placement site morbidity. In addition, rigid internal fixation eliminates the need for external or intermaxillary fixation (IMF), maintains the right dental relationships, reduces operative some time and can provide effective condylar replacement.
Allografts for mandible reconstruction are mainly made up of freeze-dried bone. Such bone grafts are just suitable for small defects from the mandible where the continuity from the mandible is intact. The benefits of allografts include the relative ease of availability without a donor defect. The main drawback to allograft material is that it is vulnerable to infection in support of supplies a matrix for osteoconduction.
Alloplastic materials are available in paste, powder, or block form which can be easily contoured to suit the required shape. The lack of osteoinductive properties secondary towards the absence of vascularity and cellular components limits the use of such material in radiated or poorly vascularized tissue. Significant failure rates (48%) are associated with implantation at radiated mandibular sites, compared to nonirradiated tissues (30%).
Allogeneic bone cribs happen to be called the ideal vehicles for particulate cancellous bone marrow grafts. Bioresorbable and biocompatible, allogeneic cribs are easily adaptable and less vulnerable to the poor graft regeneration seen with the use of alloplastic materials.
Using the development of the current microsurgical technique, the reconstructive surgeon now has a chance to make use of a composite free flap for mandibular reconstruction. In many centers, this has get to be the standard of take care of reconstructing large mandibular defects.
The fibula flap supplies a wide range of cortical bone, permitting multiple osteotomies to offer the curvature of the mandible. This flap is extremely versatile and can be harvested being an osteomyocutaneous flap by incorporating some from the soleus muscle to provide additional soft tissue bulk. The vascular pedicle is the peroneal artery and vein (as much as 8 cm length) and a skin island measuring approximately 10 × 30 cm. The free fibular graft provides as much as 24 cm in length of bony material.
There usually is sufficient bone height in the newly reconstructed mandible for future keeping a dental prosthesis. This flap provides osteocutaneous coverage that is reliable, durable and aesthetically acceptable to most patients. Disadvantages include poor donor site cosmesis, the limited amount of cutaneous tissue along with a potential donor site neurapraxia.
The iliac crest flap supplies a curved, cortical portion of bone that may be used to reconstruct the mandibular symphysis and also the curved body region; 10-14 cm of corticocancellous bone can be harvested. The vascular pedicle consists of the deep circumflex iliac artery and vein providing as much as 6 cm of length. The soft tissue island can measure as large as 16 cm in length, and it can be harvested using the internal oblique muscle. Drawbacks can include donor site morbidity, abdominal wall weakness or herniation, potential problems for the lateral femoral cutaneous nerve, and delayed postoperative ambulation.
The radial forearm free flap can be used mostly for soft tissue coverage, for example, in reconstruction of the anterior floor of the mouth following a cancer resection. This flap has limited use in mandibular reconstruction due to the limited length of radius that could be harvested, as well as the relatively short height from the harvested bone. It is based on the radial artery and venae comitantes in association using the cephalic vein.
The pedicle can measure up to twenty cm in length, making it very versatile for use in sites distant from the recipient vessels. Your skin paddle can be harvested like a sensate skin island receiving innervation in the lateral antebrachial cutaneous nerve (C5-C6). Disadvantages in using this flap include a visible donor site with potential skin graft loss over the flexor tendons and potential intra-oral hair regrowth. The nondominant forearm should be used, and adequate ulnar artery flow in the hand should be verified prior to the procedure. Preoperative laser hair removal also needs to be considered.
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