Miniplates Versus Reconstruction Bars for Oncologic Free Fibula Flap Mandible Reconstruction

Osteosynthesis for mandibular reconstruction with fibula free flap: Which type and why? A French national survey

We explored the most suitable osteosynthesis type for mandibular reconstruction using fibula free flap (FFF) given the lack of robust data available. For this, an anonymous survey was e-mailed to 853 head-and-neck surgeons (France) asking about their practices and criteria guiding their osteosynthesis material and method choices. Questions assessed: (1) the most frequently used osteosynthesis type, (2) the explanatory variables related to surgeon career status/surgical specialty, and (3) justifications for osteosynthesis type (scientific, technical, "misuse"). Multivariate logistic regression was performed to test for associations of explanatory variables with plate type or misuse. Overall, 118 (13.8%) surgeons responded, among which flexible non-locking osteosynthesis was preferred (59%). Career status and surgical specialty were significantly associated with material choice. University professors/senior lecturers (OR 5.96 vs academic clinical associates; p = 0.02), but not ear-nose-throat/reconstructive plastic surgeons (OR 0.22 vs maxillofacial surgeons; p = 0.04), were more likely to opt for rigid locking osteosynthesis. Private practitioners preferred flexible non-locking osteosynthesis (OR = 5.03; p = 0.04). Only 18% of surgeons scientifically justified their choices. We considered misuse among 65% of surgeons and this was significantly associated with irregular practice of FFF surgery (OR 2.28 vs > 10 surgeries/year; p = 0.04). Overall, >50% of surgeons mainly rely on habits without scientific arguments assisting in decision-making.

Biomechanical Evaluation of Hydroxyapatite/poly-l-lactide Fixation in Mandibular Body Reconstruction with Fibula Free Flap: A Finite Element Analysis Incorporating Material Properties and Masticatory Function Evaluation

In reconstructive surgery following partial mandibulectomy, the biomechanical integrity of the fibula free flap applied to the remaining mandibular region directly influences the prognosis of the surgery. The purpose of this study is to evaluate the biomechanical integrity of two fixation materials [titanium (Ti) and hydroxyapatite/poly-L-lactide (HA-PLLA)]. In this study, we simulated the mechanical properties of miniplate and screw fixations in two different systems by finite element analysis. A three-dimensional mandibular model was constructed and a fibula free flap and reconstruction surface were designed. The anterior and posterior end of the free flap was positioned with two miniplates and two additional miniplates were applied to the angled area of the fibula. The masticatory loading was applied considering seven principal muscles. The peak von Mises stress (PVMS) distribution, size of fixation deformation, principal stresses on bones, and gap opening size were measured to evaluate the material properties of the fixation. In the evaluation of properties, superior results were observed with both fixation methods immediately after surgery. However, after the formation of callus between bone segments at 2 months, the performance of Ti fixation decreased over time and the differences between the two fixations became minimal by 6 months after surgery. The result of the study implies the positive clinical potential of the HA-PLLA fixation system applied in fibula free flap reconstruction.

One-stage prosthodontically driven jaw reconstruction in patients with benign and malignant pathologies: A 7- to 11-year cohort study

OBJECTIVES

One stage functional jaw reconstruction is defined as the resection and reconstruction of segmental defects in conjunction with the placement of dental implants in an ideal prosthetic position and loaded with a provisional restoration, during one surgical procedure. The aim of the study is to describe clinical outcomes of patients who underwent one stage functional jaw reconstruction.

METHODS

Patients who underwent one-stage functional jaw reconstruction, from January 2013 to March 2016 were recalled in 2022 and 2023. Planning and execution for the reconstruction utilized either analogue or digital techniques. Outcome parameters recorded were treatment-related outcomes at patient level, implant-related outcomes and patient-reported outcome measures.

RESULTS

Eighteen patients underwent one-stage jaw reconstruction with a total of 57 implants. Four patients had maxillary and 14 had mandibular reconstructions. Ten patients underwent postoperative radiotherapy. Ten patients were planned using analogue and eight by digital planning. Three patients had partial flap necrosis, three patients had plate fractures, implant loss was seen in one patient and four patients died during the period. A functional prosthesis was provided in 16 out of the 18 patients.

CONCLUSION

One-stage functional jaw reconstruction is a predictable method for providing rehabilitation with successful outcomes at 7-11 years. However, caution should be exercised when the treatment modality is carried out in patients with malignant pathologies who have undergone radiotherapy.

Miniplate Versus Reconstruction Bar Fixation for Oncologic Mandibular Reconstruction with Free Fibula Flaps

BACKGROUND

 Fibula free flaps (FFF) are the gold standard tissue for the reconstruction of segmental mandibular defects. A comparison of miniplate (MP) and reconstruction bar (RB)-based fixation of FFFs has been previously described in a systematic review; however, long-term, single-center studies comparing the two plating methods are lacking. The authors aim to examine the complication profile between MPs and RBs at a single tertiary cancer center. We hypothesized that increased components and a lack of rigid fixation inherent to MPs would lead to higher rates of hardware exposure/failure.

METHODS

 A retrospective review was performed from a prospectively maintained database at Memorial Sloan Kettering Cancer Center. All patients who underwent FFF-based reconstruction of mandibular defects between 2015 and 2021 were included. Data on patient demographics, medical risk factors, operative indications, and chemoradiation were collected. The primary outcomes of interest were perioperative flap-related complications, long-term union rates, osteoradionecrosis (ORN), return to the operating room (OR), and hardware exposure/failure. Recipient site complications were further stratified into two groups: early (<90 days) and late (>90 days).

RESULTS

 In total, 96 patients met the inclusion criteria (RB = 63, MP = 33). Patients in both groups were similar with respect to age, presence of comorbidities, smoking history, and operative characteristics. The mean follow-up period was 17.24 months. In total, 60.6 and 54.0% of patients in the MP and RB cohorts received adjuvant radiation, respectively. There were no differences in rates of hardware failure overall; however, in patients with an initial complication after 90 days, MPs had significantly higher rates of hardware exposure (3 vs. 0, p = 0.046).

CONCLUSION

 MPs were found to have a higher risk of exposed hardware in patients with a late initial recipient site complication. It is possible that improved fixation with highly adaptive RBs designed by computer-aided design/manufacturing technology explains these results. Future studies are needed to assess the effects of rigid mandibular fixation on patient-reported outcome measures in this unique population.

Biomechanical feasibility of non-locking system in patient-specific mandibular reconstruction using fibular free flaps

Mandibular reconstruction with free fibular flaps is frequently used to restore segmental defects. The osteosythesis, including locking and non-locking plate/screw systems, is essential to the mandibular reconstruction. Compared with the non-locking system that requires good adaption between plate and bone, the locking system appears to present a better performance by locking the plate to fixation screws. However, it also brings about limitations on screw options, a higher risk of screw failure, and difficulties in screw placement. Furthermore, its superiority is undermined by the advancing of patient-specific implant design and additive manufacturing. A customized plate can be designed and fabricated to accurately match the mandibular contour for patient-specific mandibular reconstruction. Consequently, the non-locking system seems more practicable with such personalized plates, and its biomechanical feasibility ought to be estimated. Finite element analyses of mandibular reconstruction assemblies were conducted for four most common segmental mandibular reconstructions regarding locking and non-locking systems under incisal biting and right molars clenching, during which the influencing factor of muscles' capacity was introduced to simulate the practical loadings after mandibular resection and reconstruction surgeries. Much higher, somewhat lower, and similar maximum von Mises stresses are separately manifested by the patient-specific mandibular reconstruction plate (PSMRP), fixation screws, and reconstructed mandible with the non-locking system than those with the locking system. Equivalent maximum displacements are identified between PSMRPs, fixation screws, and reconstructed mandibles with the non-locking and locking system in all four reconstruction types during two masticatory tasks. Parallel maximum and minimum principal strain distributions are shared by the reconstructed mandibles with the non-locking and locking system in four mandibular reconstructions during both occlusions. Conclusively, it is feasible to use the non-locking system in case of patient-specific mandibular reconstruction with fibular free flaps based on the adequate safety, comparable stability, and analogous mechanobiology it presents compared with the locking system in a more manufacturable and economical way.

Postoperative facial appearance of patients with extensive oral squamous cell carcinoma can be adequately preserved with in‑house virtually planned mandibular reconstruction

The present study aimed to assess the concordance of preoperative and postoperative hard and soft tissues in patients with advanced oral squamous cell carcinoma (OSCC) following virtual surgical planning (VSP) mandibular reconstruction. In the present study, a cohort of 32 patients with OSCC underwent in-house VSP, followed by guided mandibular reconstruction utilizing vascularized free tissue grafts sourced from the fibula or scapula. A morphometric analysis was conducted comparing preoperative and postoperative three-dimensional virtual models to evaluate discrepancies and identify potential risk factors associated with poor reconstruction outcomes. The outcome variables were the differences in root mean square (RMS) and mean surface distance (MSD) resulting from the application of an iterative closest point algorithm to the virtual data. The validity of soft tissue comparison data is limited due to its susceptibility to various confounding variables. The present study conducted a comprehensive re-evaluation of these variables. High tumor stage, positive N status and the use of adjuvant therapy contributed to more noticeable differences in preoperative and postoperative facial soft tissue appearance. The accuracy of postoperative bone reconstruction results was higher in patients who underwent neomandibular formation using a fibular graft compared with those who received a scapular graft. Preoperative and postoperative soft tissue analyses were conducted for comparison. The MSD showed a deviation of 3.2 mm (± 2.0 mm SD; range 1.3-9.5 mm), whereas the RMS was 5.3 (± 2.9 SD; range 2.1-14). In conclusion, in-house VSP and guided mandibular reconstructions can yield clinically accurate results, preserving patient appearance and offering the advantage of rapid feasibility.

Mandibular reconstruction in head and neck cancer: which is the gold standard?

INTRODUCTION

The aim of this study is to perform a systematic review to compare the outcomes of the different surgical options for mandibular reconstruction in head and neck cancer.

MATERIAL AND METHODS

93 articles were selected. Four groups were identified: titanium plate without flaps, titanium plate covered by soft tissue flap, bone tissue flaps and double flaps. We compared patients' characteristics, site of mandibulectomy, type of reconstruction and complications.

RESULTS

4697 patients were reported. The groups were not homogeneous regarding the type of defect and the treatment history. A significant difference in terms of post-operative complications was found between group 1 and group 2 (p < 0.00001), and between group 2 and group 3 (p < 0.00001). Total complications rate for group 4 was significantly higher when compared to group 3 (p < 0.00001), but no significant difference was found with group 2.

CONCLUSION

These results suggest that mandibular reconstruction using a microvascular bone flap is the best surgical option in patients without significant comorbidities.

The Precision of Different Types of Plates Fabricated With a Computer-Aided Design and Manufacturing System in Mandibular Reconstruction With Fibular-Free Flaps

Computer-assisted surgery (CAS) has been introduced to mandible reconstruction with fibular-free flap in cutting guide placement. When CAS cooperates with different plate fixations, the results show various degrees of errors by which this study aimed to evaluate. Mock surgeries were conducted in 3D-printed mandibles with 2 types of defects, limited or extensive, reconstructed from 2 ameloblastoma patients. Three types of fixations, miniplate, manually bending reconstruction plate, and patient-specific plate, are tested, each of which was performed 3 times in each type of defect, adding up to 18 surgeries. One with the least errors was selected and applied to patients whose 3D-printed mandibles were derived. Finally, in vivo errors were compared with the mock. In limited defect, average errors show no statistical significance among all types. In extensive defect, patient-specific plate had a significantly lower average condylar error than manually bending reconstruction plate and miniplate (8.09±2.52 mm vs. 25.49±2.72 and 23.13±13.54 mm, respectively). When patient-specific plate was applied in vivo , the errors were not significantly different from the mock. Patient-specific plates that cooperated with CAS showed the least errors. Nevertheless, manually bent reconstruction plates and miniplates could be applied in limited defects with caution.

Unicortical Bone Necrosis of the Fibula Free Flap Associated to the Fixation with a Nonlocking 2.0-mm Reconstruction Plate and Screws

The authors present a unique case of osteonecrosis of a cortical half of a fibula free flap that has not been reported in the literature yet. This complication was associated with the impairment of the vascularization of periosteum in the cortical half of fibula that was fixated with a nonlocking reconstructive 2.0-mm plate and screws but other factors could have been involved. The patient was submitted to excision of a cemento-ossifying fibroma that resulted in a left hemimaxilectomy mesoinfrastructure defect classified as the Cordeiro type 2B. The 42-year-old female patient was submitted to reconstruction with an osteomusculocutaneous fibula free flap plus a segment of fibula graft. The two bone segments of the free flap used to reconstruct the anterior and left alveolar crest were fixated with a reconstructive 2.0-mm plate of matrixMANDIBLE system. The only reported complication was an oronasal fistula that healed with conservative treatment and the referred osteonecrosis of the external cortical half of the fibula free flap with plate exposure at 2.5 years postoperatively. Surgical excision of the osteonecrosed cortical half of the fibula with the plate and screws was performed, while the other cortical underwent bone union as corroborated by computed tomography scans.

Mini-plate versus reconstruction bar fixation for oncologic mandibular reconstruction with free fibula flaps: A systematic review and meta-analysis

Introduction There is currently no consensus as to the comparative complication profiles of mini-plate (MP) and reconstruction bar (RB) osseous fixation in fibula flap mandibular reconstruction. The aim of this study is to compare complication rates associated with the use of MP versus RB fixation for vascularized fibula free flap (FFF) reconstruction of oncologic mandibular defects in an effort to better guide hardware utilization and pre-operative virtual surgical planning methods. Methods A systematic review and meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, EMBASE, and Cochrane Library databases were queried to identify studies related to FFF-based mandibular reconstruction with either MP or RB fixation. Primary endpoints of interest were plate complications, wound infection, mal- or non-union, and total flap loss. Complication rates were calculated as weighted proportions and compared via Fisher's exact testing. Results Sixteen studies met inclusion criteria, which examined 1,513 patients. Only three studies directly compared MP fixation with RB fixation. MP fixation was used in 828 (54.7%) cases and RB fixation in 685 (45.3%) cases. MP fixation demonstrated greater rates of plate-related complications (32.5% versus 18.8%, p < 0.01, respectively), fistula formation (15.8% versus 4.7%, p = 0.04), total flap loss (9.4% versus 4.7%, p = 0.02), partial flap loss (20.6% versus 6.1%, p < 0.01), and re-operation for vascular compromise (13.3% versus 4.0%, p < 0.01). Rates of infection, mal-union/non-union, and wound dehiscence were similar across both groups. Conclusion Our results suggest that MP use may be associated with higher rates of plate-related complications. Though limited by outcome reporting heterogeneity, this review can serve as a template for future investigations evaluating the safety profiles of MP and RB fixation in head and neck surgery.

Updates in Management of Craniomaxillofacial Gunshot Wounds and Reconstruction of the Mandible

This article includes updates in the management of mandibular trauma and reconstruction as they relate to maxillomandibular fixation screws, custom hardware, virtual surgical planning, and protocols for use of computer-aided surgery and navigation when managing composite defects from gunshot injuries to the face.

Donor- and recipient-site morbidity of vascularized fibular and iliac flaps for mandibular reconstruction: A systematic review and meta-analysis

The aim of this article is to evaluate the early and late morbidities of the donor- and recipient-site in patients undergoing mandibular reconstruction using either vascularized fibular flap (VFF) or vascularized iliac flap (VIF). Electronic databases, including PubMed, Web of Science, Cochrane Central and Embase, were explored for literature published until October 2020. A total of twenty-four articles reporting complications following mandibular reconstruction surgery with follow-up periods ranging from six to 63 months were selected based on the exclusion criteria. For each research, the JBI Critical Assessment Tool and the ROBINS-I Tool were used to analyze the methodological quality and the risk of bias. A single-arm meta-analysis was performed to have a synthesized analysis of the donor- and recipient-site early and late morbidities. Results showed that the early morbidities in VFF group ranged from 3% to 12%, and the late morbidities in VFF group ranged from 5% to 67%. In VIF group, the early morbidities ranged from 3% to 16%, and the donor-site late morbidities ranged from 6% to 43%. Complications with the top three morbidities in the VFF group were: chronic sensory disturbances at the donor-site (67%), malocclusion (22%) and chronic lower limb weakness (20%); and in the VIF group were: chronic sensory disturbances at the donor-site (43%), chronic pain at the donor-site (26%), chronic gait disturbance (20%). Further controlled clinical trials are needed to assess the long-term outcome of VFF or VIF grafting.

Complication analysis of three different designs of temporary mandibulotomy in tongue cancer treatment

BACKGROUND

Mandibulotomy helps access posterior oral cavity tumors. If osteotomy designs affect postoperative and postradiotherapy complications, needs to be tested clinically.

METHODS

Two hundred and eighteen patients who underwent midline mandibulotomy for primary tongue cancer wide excision and flap reconstruction at Chang Gung Memorial Hospital during 2014-2019.

RESULTS

There were 114 straight, 54 notched, and 50 stair-stepped osteotomy cases. Stair-stepped osteotomy had less advanced tumor stages (P = .009) and notched osteotomy more common single-plate fixations (P = .012). The former showed higher mandibular heights (P = .000) and more intact midline teeth (P = .011) than notched and straight ones. Straight osteotomy cases showed lower early infection rates (P = .039). Single-plate fixation was related to more flap dehiscence (P = .001) and oro-cutaneous fistulas (P = .035).

CONCLUSIONS

Complex osteotomy does not offer long-term benefits in midline mandibulotomies for primary tongue cancers and has higher early infections. Single-plate fixation increases postoperative complications.

Retrospective analysis of complications in 190 mandibular resections and simultaneous reconstructions with free fibula flap, iliac crest flap or reconstruction plate: a comparative single centre study

Objectives

The purpose of this study was to evaluate the incidence of complications following mandibular reconstruction and to analyse possible contributing factors.

Materials and methods

Clinical data and computed tomography scans of all patients who needed a mandibular reconstruction with a reconstruction plate, free fibula flap (FFF) or iliac crest (DCIA) flap between August 2010 and August 2015 were retrospectively analysed.

Results

One hundred and ninety patients were enrolled, encompassing 77 reconstructions with reconstruction plate, 89 reconstructions with FFF and 24 reconstructions with DCIA flaps. Cutaneous perforation was most frequently detected in the plate subgroup within the early interval and overall (each p = 0.004). Low body mass index (BMI) and total radiation dosage were the most relevant risk factors for the development of analysed complications.

Conclusions

Microvascular bone flaps have overall less skin perforation than reconstruction plates. BMI and expected total radiation dosage have to be respected in choice of reconstructive technique.

Clinical relevance

A treatment algorithm for mandibular reconstructions on the basis of our results is presented.

Electronic supplementary material

The online version of this article (10.1007/s00784-020-03607-8) contains supplementary material, which is available to authorized users.

Complications After Soft Tissue With Plate vs Bony Mandibular Reconstruction: A Systematic Review and Meta-analysis

OBJECTIVE

Mandibular reconstruction for segmental defects is a well-studied topic. However, there are conflicting data on the risks of delayed plate-related complications. The objective of this systematic review and meta-analysis was to assess long-term plate-related complications following reconstruction of the mandible with soft tissue and a plate as compared with immediate vascularized bony reconstruction.

DATA SOURCES

A medical librarian created search strategies with a combination of keywords and controlled vocabulary in Ovid Medline (1946-), Embase (1947-), Scopus (1960-), Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Clinicaltrials.gov.

REVIEW METHODS

Candidate articles were independently reviewed by 2 authors. Inclusion/exclusion criteria were uniformly applied. Articles were considered eligible if they included adequate reporting of plate extrusion and/or fracture and had follow-up ≥12 months.

RESULTS

A total of 2379 patients were included. The risk of plate fracture was low in cases of soft tissue with a plate (5%; 95% CI, 0.03-0.08) and osseous reconstruction (1%). The risk of extrusion following soft tissue and plate reconstruction was 20% (95% CI, 0.15-0.27). In the osseous reconstruction group, the risk of extrusion was 10% (95% CI, 0.06-0.18). Revision surgery was performed twice as often following soft tissue with a plate as compared with vascularized bony reconstruction (32% [95% CI, 0.25-0.40] vs 14% [95% CI, 0.09-0.21], respectively).

CONCLUSION

Delayed plate-related complications remain a significant problem following segmental defect reconstruction. Soft tissue and plate reconstruction techniques may increase the risk of plate removal and revision surgery.

Fibula free flap in maxillomandibular reconstruction. Factors related to osteosynthesis plates' complications

The aim of this paper is to identify risk factors associated with the development of osteosynthesis plates' related complications in fibula free flap reconstructions. This is a case series study of consecutive fibula free flaps. Clinical and radiological variables were recorded. Patient outcomes were evaluated with special attention to osteosynthesis plates' related complications; these included plate exposure, plate fracture, loosening of screws, non-union, bone resorption, oro-cutaneous fistulas, and bone exposure. We have done a descriptive analysis, univariate analysis, and multivariate logistic regression model to explore possible risk factors for osteosynthesis plates' related complications. Data analysis was performed using R software (version 3.5.0). 111 fibula free flaps were studied. 29 patients (26.1%) developed osteosynthesis plates' related complications. The mean time to osteosynthesis plates' related complications was 22 months; range (1-120); the median and mode were 12 months. Patients with preoperative radiotherapy (34% vs 14%, p = 0.021), and secondary reconstruction (31% vs 15%, p = 0.053) had a higher incidence of osteosynthesis plates' related complications. In the univariate analysis, "preoperative radiotherapy" (OR 3.07, 95%CI = 1.139-8.242, p = 0.025) and "extraoral soft-tissue defect" (OR 2.907, 95%CI = 1.032-8.088, p = 0.042) were risk factors for osteosynthesis plates' related complications. We have observed an interaction effect: patients with mandibular Brown's classes III + IV and "secondary reconstruction" have a higher risk for osteosynthesis plates' related complications; more than 47.30 times compared to Brown's class I and "primary reconstruction" (p = 0.026). Different factors may contribute to the development of osteosynthesis plates' related complications. Our study adds important information about these. Patients with higher risk of developing complications should be informed that a second intervention to remove the plates might be necessary.

Complication rates and clinical outcomes of osseous free flaps: a retrospective comparison of CAD/CAM versus conventional fixation in 128 patients

Studies evaluating plate-related complications in patient-specific versus conventional fixation systems in free flap surgery are lacking. This was a retrospective study of 128 osseous free flaps with a minimum follow-up of 12 months. Wound healing disorders, plate exposure, fixation failure, and subtotal osseous union were recorded and evaluated statistically by univariate and regression analysis. Complication rates were as follows: wound healing disorders 33.6% (computer-aided design and computer-aided manufacturing (CAD/CAM) vs. conventional: 35.1% vs. 33.0%); plate exposure 21.9% (29.7% vs. 18.7%); fixation failure 7.0% (8.1% vs. 6.6%); subtotal osseous union 36.7% (45.9% vs. 33.0%). Radiotherapy (P<0.001) and more than two segments (P=0.026) were independent variables for the overall complication rate and were negatively correlated with the dental implantation rate. The time between diagnosis and ablative surgery was increased by 11.0days in the CAD/CAM group (34.2±16.2days vs. 23.2±12.0 days; P=0.002). Rates of dental rehabilitation were not significantly different (35.1% vs. 44.0%, P=0.358). On average, 3.2±1.7 dental implants were placed into flap segments. Plate-related complications were increased with radiotherapy and multisegment flaps. There was a non-significant trend towards increased complications with patient-specific plates in comparison to conventional reconstruction plates.

Evaluation and reduction of magnetic resonance imaging artefacts induced by distinct plates for osseous fixation: an in vitro study @ 3 T

OBJECTIVES:

To analyze MRI artefacts induced at 3 T by bioresorbable, titanium (TI) and glass fibre reinforced composite (GFRC) plates for osseous reconstruction.

METHODS:

Fixation plates including bioresorbable polymers (Inion CPS, Inion Oy, Tampere, Finland; Rapidsorb, DePuy Synthes, Umkirch, Germany; Resorb X, Gebrueder KLS Martin GmbH, Tuttlingen, Germany), GFRC (Skulle Implants Oy, Turku, Finland) and TI plates of varying thickness and design (DePuy Synthes, Umkirch, Germany) were embedded in agarose gel and a 3 T MRI was performed using a standard protocol for head and neck imaging including T₁W and T₂W sequences. Additionally, different artefact reduction techniques (slice encoding for metal artefact reduction & ultrashort echo time) were used and their impact on the extent of artefacts evaluated for each material.

RESULTS:

All TI plates induced significantly more artefacts than resorbable plates in T₁W and T₂W sequences. GFRCs induced the least artefacts in both sequences. The total extent of artefacts increased with plate thickness and height. Plate thickness had no influence on the percentage of overestimation in all three dimensions. TI-induced artefacts were significantly reduced by both artefact reduction techniques.

CONCLUSIONS:

Polylactide, GFRC and magnesium plates produce less susceptibility artefacts in MRI compared to TI, while the dimensions of TI plates directly influence artefact extension. Slice encoding for metal artefact reduction and ultrashort echo time significantly reduce metal artefacts at the expense of scan time or image resolution.

Novel Patient-Specific 3-Dimensional Printed Fixation Tray for Mandibular Reconstruction With Fibular Free Flaps

Segmental mandibular defects secondary to infectious, traumatic, and pathologic conditions can be debilitating because of their impact on function and facial esthetics. Several reconstructive techniques are available, with vascularized flaps commonly used for the reconstruction of large bony or composite segmental defects. The free fibular flap for mandibular reconstruction is well documented and remains a commonly used flap because of its bone length, versatility, distant location from the head and neck region that allows for a 2-team approach, and ability to simultaneously place endosseous implants. Virtual surgical planning (VSP) and guided resection and reconstruction of maxillofacial defects have facilitated complex 3-dimensional (3D) reconstruction. The accuracy and fidelity of VSP are dependent on the intraoperative execution of the VSP, with computer-aided design and computer-aided modeling of patient-specific cutting guides and hardware providing a template for its execution. The goal of this report is to describe the authors' experience with the use of a novel 3D printed fixation tray designed from the VSP data. It provides dual functionality by aiding in alignment and stabilization of the fibular segments and concomitantly providing patient-specific anatomic references for indexing of bony and soft tissue components. This tray enables rapid ex vivo configuration of the fibula segment(s) with the reconstruction bar relative to the native mandibular segments and allows the compiled construct to be transferred to the head and neck for insetting as a precisely configured single unit.

Updates in Management of Craniomaxillofacial Gunshot Wounds and Reconstruction of the Mandible

This article includes updates in the management of mandibular trauma and reconstruction as they relate to maxillomandibular fixation screws, custom hardware, virtual surgical planning, and protocols for use of computer-aided surgery and navigation when managing composite defects from gunshot injuries to the face.