Mandible

The goals of mandibular reconstruction are to reconstitute the mandibular arch and to allow for dental restoration. The bone available with pedicled flaps, such as the trapezius or scapular spine, is inadequate for dental implantation; moreover, non-vascularized bone heals by slow substitution of bone stock and is not suitable for patients who will need radiation within 6 weeks of surgery.29 For lateral mandible defects that do not involve the symphysis, the criterion for reconstruction with bone remains unclear. Provided that good mobility of the tongue is present, most patients can swallow effectively after segmental resection, even with mandibular drift and malocclusion. In these patients, an expedient option entails either no reconstruction of the mandible or a reconstruction plate covered with a radial forearm flap to stabilize the mandible.2'29 Using this technique, exposure of the plate has been noted in 5% of patients with lateral and posterior defects. In anterior defects, the exposure rate increases to 20%, probably due to the resection of the depressor muscles of the mandible, which permit unopposed retraction of the plate superiorly through the flap.33

Patients with more extensive resection of the mandible, particularly the anterior segment, must undergo reconstruction in order to restore contour, swallow effectively, and avoid the problems of salivary incontinence. Several flaps have been described for mandibular reconstruction; in our experience, the fibular osteocutaneous flap and the radial forearm osteocutaneous flap have advantages over the iliac crest and scapular flap.2 The radial forearm osteocutaneous flap has a more reliable skin paddle than the fibular osteocutaneous flap, but only 30% of the radius can be harvested for bone, and osseointegrated implants are not possible, owing to a lack of adequate bone stock. The radial flap is an excellent choice for straight segmental resections of the posterior body of the mandible and for lateral defects requiring only one osteotomy to reconstruct the posterior body and inferior portion of the ascending ramus.2 It is our flap of choice where soft tissue sacrifice in the retromolar trigone, tonsillar fossa, lateral floor of mouth, and hypopharyn-geal areas requires reconstruction and bone replacement is desired. The fibular osteocutaneous flap offers up to 25 cm of bone of sufficient height and is specifically indicated for reconstruction of anterior defects, for large defects from parasymph-ysis to ascending ramus, and for patients requiring eventual osseointegration.29 The major drawback of this flap is the questionable reliability of the overlying skin paddle, which depends on small perforating branches lying in the septum between the peroneal and soleus muscles. The flap has been modified to include a cuff of soleus muscle to improve the reliability of the skin paddle. The major advantage of using free microvascular bone flaps for oral cavity reconstruction is that the chances for bone healing and tolerating radiation therapy are far better than with conventional bone grafts.

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