In my experience, the patient and family are usually more concerned about the ear defect initially, so the auricular surgery is usually under way before other corrections begin. By carefully planning the auricular location with reference to the opposite, normal side, one should be able to meet this psychological urgency without compromising the other facial repairs. If mandibular and/or soft tissue repairs are begun before the ear, then every effort must be taken to preserve the virgin auricular site and keep it scar-free.
In microtia patients whose jaws are also underdeveloped, bony repairs are indicated both to improve facial contours and to correct dental occlusion. These repairs are done after the auricular construction, and are accomplished by dividing and bone grafting to elongate the jaws, correct tilts, and add bulk (see Fig. 8) [67, 77].
Fig. 8 - Correcting the bony abnormalities of hemifacial microsomia
8a - The bony deformities. Note how deficiencies of upper and lower jaws create tilt of the bite.
8b - Note lines that depict where saw cuts must be made to level the bite; a wedge will be removed from the maxilla (upper jaw); the chin will be repositioned.
8c - Once the jaws and chin have been correctly realigned, a rib graft is used to construct the deficient jaw upright.Figure 9 - Jaw lengthening by bony distraction (after McCarthy).
Divided jaw bone is slowly distracted by external device. By distracting the bone segments slowly (1 millimeter per day), new bone is able to grow within the increasing gap which is brought to a maximum elongation during several weeks. The device is left in place an additional six to eight weeks until there is X-ray evidence of good bone formation within the gap.