**3. Microvascular composite tissue transplantation**

**2. Assessment of maxillomandibular defects**

622 A Textbook of Advanced Oral and Maxillofacial Surgery Volume 2

**Figure 1.** Four implants placed after a fibula flap graft.

Each defect is individualized according to the missing component. In the maxillomandibular area the size of soft tissue as well as bone defect, the underlying etiology (cancer, trauma, and infection), anatomic location, aesthetic visibility, associated functional disabilities and the availability of a local and or distant donor site should be evaluated. [5] Compatibility of the donor tissue with the area being reconstructed should be considered with regard to skin color, texture, thickness of soft tissue, bone quantity and quality and also shape of the bone compo‐ nent to restore the mandible and maxilla; further restoration with dental implants can be done. It has been shown that any mandibular defect greater than 6.0 cm is prone to failure and thus free flaps in these defects are indicated.[6] Restoration of stable retentive dentition is a prerequisite to a successful functional oral rehabilitation. This is best achieved with endosseous implants, capable of supporting a stable dental prosthesis, placed directly into vascularized bone flaps at the time of mandibular reconstruction The iliac crest is the most consistently implantable donor site, followed by the scapula, fibula, and radius (with 83%, 78%, 67%, and 21% of sections from each donor site satisfying the criteria for implantability respectively). Consistent regional differences in implantability were encountered at each donor site except the scapula. [7] In a cadaver study, the dimensions of bone available for implant placement from the iliac crest, scapula, fibula, and radius osseous flaps were measured. The iliac crest and fibula flaps had bone dimensions consistently adequate for implant placement. Bone availability for the safe placement of implants into the scapula flap was found in the majority of specimens. The radius flap group had the highest number of specimens that were inadequate for implant placement. [8] Another study demonstrated that nearly all of the iliac crests had adequate dimensions for the positioning of four 10 mm implants. In 63% of the scapulae, it

In the maxillomandibular area, surgeons encounter soft and hard tissue defects due to ablation of cancer or severe destructive trauma. After introducing the ability to repair vessels less than 2 mm in diameter, microvascular transplantation found its place in reconstruction surgery. A microvascular composite transplantation was defined as a composite flap (soft and hard tissue with their associated blood supply) which is removed from a part of the body and anastomosed to the recipient site vessels. It has been shown that a reliable anastomosis can be achieved with an external lumen diameter of 0.5 to 2mm with a patency rate of 95%. [10]

The frequency of using various free flaps is different according to defect site, the surgeon's experience and condition of the patient. In a retrospective study, flap donor sites included radial forearm (n = 183), fibula (n = 145), rectus abdominis (n = 38), subscapular system (n = 28), iliac crest (n = 5), and a jejunal flap. Age, sex, diagnosis, comorbidities, tumor stage, defect site, primary vs. secondary reconstruction, and history of surgery, radiation therapy, or chemotherapy were considered for choosing a flap. [11]
