Functional Outcome of CAD/CAM-Assisted versus Conventional Microvascular, Fibular Free Flap Reconstruction of the Mandible: A Retrospective Study of 30 Cases

Abstract

Different advantages of virtually planned and guided mandibular reconstructions have been described. Functional analyses and comparisons with conventionally reconstructed patients. We retrospectively analyzed 30 cases of mandibular reconstructions that involved virtually planned or conventional microvascular, fibular free flaps that occurred between April 2011 and December 2014 at a single center. The results were also compared with a healthy cohort of 30 participants. Axiographic measurements were performed postoperatively, and uni- and multivariate regressions analyses were performed to determine the association between possible predictor variables on functional outcome. Operation time, hospital stay, number of osteotomies, incidence of postoperative temporomandibular joint pain, noise, and tension did not differ significantly between the conventional and computer-aided design/computer-aided manufacturing (CAD/CAM) groups (each > 0.05). Mouth opening and protrusion and laterotrusion also did not differ significantly (each > 0.05) but were significantly reduced compared with the healthy group. Univariate analysis showed a significant influence of postoperative irradiation on mouth opening and laterotrusion in the conventional group ( = 0.047 and = 0.028). In addition, multivariate analysis showed a significant influence of indication and number of osteotomies on laterotrusion ( = 0.005 and = 0.043). Uni and multivariate analyses revealed a significant influence of indication, preoperative irradiation, and number of osteotomies on protrusion and mouth opening in the CAD/CAM group ( = 0.016, = 0.044, and = 0.028). CAD/CAM-assisted reconstructions of the mandible give comparable functional results with those of the conventional technique, but no functional superiority has been established. Nevertheless, the integration of virtual planning and guided surgery is definitely of significant value but should be indicated individually case by case.

Innovative CAD/CAM Guide for Mandibular Reconstruction with Metallic Condylar Head and Free Fibular Flap

“…In mandibular reconstruction using an FF after segmental mandibular resection, a guide constructed using CAD/CAM enabled more accurate reconstruction. 7 Such prostheses had an average postoperative deviation of the condyle from the preoperative position of 3.8 mm (range 1.3–6.7). 8 However, for reconstructions not including the condyle using a CAD/CAM guide, the postoperative deviations from the virtual plan were 2.4 mm 9 and 2.7 mm.…”

“…The advantage of using a CAD/CAM guide for the latter operation has been reported. 7 , 9 In such mandibular reconstructions, even if surgeons do not use the CAD/CAM guide, they can image the reproduction position easily by intermaxillary fixation because both ends of the mandible are retained. However, when reconstructing the mandible after hemimandibulectomy including the condyle, it is more difficult to image the final position even when setting intermaxillary fixation because there are few landmarks, and there is only the healthy side of the mandible remaining.…”

“…5 Mandibular reconstruction using a fibular flap (FF) and a computer-aided design and manufacture (CAD/CAM) guide now facilitates such reconstruction. 6 , 7 Therefore, we used CAD/CAM to design a guide for MC reconstruction with a metallic condylar head (CH) and a free FF after hemimandibulectomy including the condyle. Using this guide, fibular blocks and a metallic CH were fixed together, completely mirroring the diseased mandible before detachment of the FF from the leg.…”

Advantages of surgical simulation in the surgical reconstruction of oncological patients

“…With the introduction of virtually-designed surgical guides, this complexity decreases, as these guidelines allow the surgeon to plan the reconstruction with greater precision to maximize the final result ( 4 , 12 ).…”

“…Several studies have pointed to a greater accuracy in the design of fibular graft osteotomies with the use of computer-aided surgical guides ( 3 , 4 , 12 - 19 ). In a control case study of 38 patients treated by mandibular reconstructions with fibula grafts, Hanasono et al ( 14 ) concluded that CAD/CAM and stereolithographic models increased their accuracy and speed.…”