Standardized Templates for Shaping the Fibula Free Flap in Mandible Reconstruction

Abstract

Conversion of the straight fibula bone flap into the parabolic mandible shape can be performed using customized acrylic templates made from a 1:1 mandible computed tomography scan and lateral cephalogram. The premise of the current study is to objectively quantify the variability in a series of acrylic templates used for mandible reconstruction to assess the feasibility of creating a standardized template.

In this study acrylic templates of 48 consecutive adult dentate patients who underwent fibula flap mandible reconstruction from 1994 to 1999 were evaluated. Osteotomy angles for the mandibular angle, midbody and parasymphysis, and length of each bony segment were determined using a metric ruler and protractor. Values were reported as means ± standard deviation.

The mean mandibular angle measured 122.6 ± 6.4 degrees, while the midbody and parasymphysis angles were 153 ± 4.5 degrees and 130 ± 4.2 degrees, respectively. Mean bone segment lengths were: ramus 64.5 ± 9.8 mm, distal body 47.6 ± 4.2 mm, mesial body 40.6 ± 3.2 mm, and symphysis 18.5 ± 2.2 mm.

It was concluded that the evaluation of patient acrylic templates used in a series of mandible reconstructions demonstrates osteotomy angles vary minimally (3–5%). Bone segment lengths vary from 10 to 15%, suggesting heterogeneity in mandible size. A standard template can be used to shape the fibula in most mandible reconstructions eliminating the need for routine preoperative imaging or costly fabricated computer-aided design/computer-aided manufacturing cutting guides.

Keywords

template - mandible - CAD CAM

• References

• 1 Hidalgo DA. Aesthetic improvements in free-flap mandible reconstruction. Plast Reconstr Surg 1991; 88 (4) 574-585, discussion 586–587
• 2 Kahler SH, Manders EK. Planned angle osteotomy. Plast Reconstr Surg 1991; 87 (5) 969-973
• 3 Tsuchiya S, Sakuraba M, Asano T , et al. Morphologic study of mandibles in Japanese patients for mandibular reconstruction with fibula free flaps. Head Neck 2011; 33 (3) 383-388
• 4 Xu LQ, Zhang CP, Poh EH, Yin XL, Shen SK. A novel fibula osteotomy guide for mandibular reconstruction. Plast Reconstr Surg 2012; 129 (5) 861e-863e
• 5 Bähr W. Blood supply of small fibula segments: an experimental study on human cadavers. J Craniomaxillofac Surg 1998; 26 (3) 148-152
• 6 Chang EI, Clemens MW, Garvey PB, Skoracki RJ, Hanasono MM. Cephalometric analysis for microvascular head and neck reconstruction. Head Neck 2012; 34 (11) 1607-1614
• 7 Antony AK, Chen WF, Kolokythas A, Weimer KA, Cohen MN. Use of virtual surgery and stereolithography-guided osteotomy for mandibular reconstruction with the free fibula. Plast Reconstr Surg 2011; 128 (5) 1080-1084
• 8 Hanasono MM, Jacob RF, Bidaut L, Robb GL, Skoracki RJ. Midfacial reconstruction using virtual planning, rapid prototype modeling, and stereotactic navigation. Plast Reconstr Surg 2010; 126 (6) 2002-2006
• 9 Hirsch DL, Garfein ES, Christensen AM, Weimer KA, Saddeh PB, Levine JP. Use of computer-aided design and computer-aided manufacturing to produce orthognathically ideal surgical outcomes: a paradigm shift in head and neck reconstruction. J Oral Maxillofac Surg 2009; 67 (10) 2115-2122
• 10 Roser SM, Ramachandra S, Blair H , et al. The accuracy of virtual surgical planning in free fibula mandibular reconstruction: comparison of planned and final results. J Oral Maxillofac Surg 2010; 68 (11) 2824-2832
• 11 Sink J, Hamlar D, Kademani D, Khariwala SS. Computer-aided stereolithography for presurgical planning in fibula free tissue reconstruction of the mandible. J Reconstr Microsurg 2012; 28 (6) 395-403