Oral Max Surgery Clinics Sample Article

Bone Grafting the Mandible Patrick J. Louis, DDS, MD Multiple bone grafting techniques have been used to reconstruct the partially dentate and edentulou s mandible. 1–6 Many of these techniques have been successful. In this article, the vario us bone graf ting techniques to reconstruct mandibular defects are reviewed. Other issues discussed include whether autogenous bone is necessary for reconstruction of the man dib ula r rid ge and the imp ortance of membranes. BLOCK ONLAY GRAFTS Block onlay grafts have been used extensively for reconstruction of mandibular alveolar defects. 7–11 Autogenous and nonautogenous options are avail- abl e for ver tic al and hor izontal deficienci es of the mandible. Autogenous bone grafts have the advantage of transferring osteogenic cells to the reci pien t site. 12–15 Autogenous donor sites for blo ck gra fts inc lud e the cal var ium, man dib le, zygoma, an d ilium. In tr amembranou s bone (calvarium, mandible, and zygoma) has the advantage of decreased rates of resorption compared with endochondral bone (ilium), due to its dense cortical structure and microarchitecture. 16–20 When a small amount of bone is needed, local grafts harvested from the mandibular symphysis or ramus have been used extensively ( Fig. 1 ). 10,21–24 These sources have the advantage of being convenient due to their proximity to the reconstruction sit e and low risk of morbidity. 25 The disadvantage of the mandible as a bone source is the limite d amount of bon e ava ila ble and the fact that mandibular harvesting can some- times interfere with the planned reconstruction if too clo se to the reconstruction site ( Tabl e 1 ). 26 The most common post operative morbidit y associated with chin and ramus grafts has been reported as temporary paresthesia. For the chin it ranges from 10% to 50%, and for the ramus, it ranges from 0% to 5%. 21,27 The zygomaticomaxil- lary region also can be used as a harvest si te. 28 The adv ant ageof thi s sit e is tha t whe n per for min g gra fts in the maxilla, simple extension of the incision is needed. The procedure is associated with a low risk of morbidity. The disadvantage is the limited amount of bone available. Other sites tha t can be used are the maxillary tuberosity and tori. 29–31 Distant site bone harvesting is indicated when a lar ge gra ft is needed (se e Table 1 ). 5,8,17,32–36 Sites that have been reported as reliable include the calvarium and the ilium ( Fig. 2 ). The tibia can be used for harvesting cancellous bone; however, a small amount of block cortical bone also can be harvested. 37,38 When cancellous bone is needed, the tibia is chosen, because it yields an abundant amount with a relatively low risk of morbidity. 39–41 The types of gra fts har ves ted fro m the cal var ium and the ilium are entirely different. Calvarial grafts are usu all y har ves ted in str ips fro m the par iet al bone. The average thickness of the parietal bone is 7.45 mm. 42,43 A split thickness harvest tech- nique is used, which can yield graft thicknesses of approximately 3 mm. The main advantage of cal var ial gra fts is the ir den se cor tic al str uct ure that resists resorption. 16–18 The amount of avail- abl e cor tic al gra ft is abu nda nt. Howeve r, thi s procedure usually requires general anesthesia in a hos pit al or ambula tor y car e set tin g, but there are a few reports of office based techniques. 44,45 The incidence of compli cat ion is low, wit h the most common reported complication being sero- ma/hematoma. 46 Larger amounts of bone can be harvested from the ilium, but these grafts typically Oral and Maxillofacial Surgery, School of Dentistry, University of Alabama at Birmingham, 1919 7th Avenue South, SDB 419, Birmingham, AL 35294, USA E-mail address: [email protected] KEYWORDS Bone grafting Mandible Dentate Edentulous Oral Maxillofacial Surg Clin N Am 23 (2011) 209–227 doi:10.1016/j.coms.2011.01.002 1042-3699/11/$ – see front matter 2011 Elsevier Inc. All rights reserved. o r a l m a x s u r g e r y . t h e c l i n i c s . c o m

Oral Max Surgery Clinics Sample Article

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