Miniplates Versus Reconstruction Plates in Vascularized Osteocutaneous Flap Reconstruction of the Mandible:

Risk Factors for Plate Infection, Exposure, and Removal in Mandibular Reconstruction

OBJECTIVE

Mandibular plate reconstruction (MPR) is often indicated after tumor ablation, osteoradionecrosis excision, and traumatic bone loss to restore oral functionality and facial cosmetics. There are limited analyses identifying risk factors that lead to plate infection (PIn), exposure, and removal ("plate complications").

STUDY DESIGN

Retrospective cohort study.

SETTING

Academic tertiary medical center.

METHODS

Patients who underwent MPR from 2013 to 2022 were identified. Risk factors for plate complications were analyzed based on demographic, clinical, intraoperative, and postoperative factors. Multivariable analysis was conducted with logistic regression. Survival analysis was conducted with a Cox model.

RESULTS

Of the 188 patients analyzed, 48 (25.5%) had a plate complication [infection: 22 (11.7%); exposure: 23 (12.2%); removal: 35 (18.6%)]. Multivariate analysis revealed predictive associations between at least 1 plate complication and the following variables: smoking status, soft tissue defect size, number of plates, average screw length, and various postoperative complications. Other associations approached the threshold for significance. Prior and adjuvant radiation therapy, type of free flap, stock versus custom plates, and perioperative antibiotic prophylaxis regimens were not associated with plate complications. No plate complication was independently associated with lower overall survival. PIn (hazard ratio, HR: 7.99, confidence interval, CI [4.11, 15.54]) and exposure (HR: 3.56, CI [1.79, 7.08]) were independently associated with higher rates of plate removal.

CONCLUSION

Plate complications are relatively common after MPR. Smoking history, specific disease characteristics, hardware used during surgery, and postoperative complications may help identify higher-risk patients, but additional larger-scale studies are needed to validate our findings and resolve discrepancies in the current literature.

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.

Plate-related complication and health-related quality of life after mandibular reconstruction by fibula flap with reconstruction plate or miniplate versus anterolateral thigh flap with reconstruction plate

BACKGROUND

Plate-related complications are major long-term complications in mandible reconstruction. There are controversies regarding the use of a reconstruction plate versus miniplates and a bone flap versus a soft tissue flap with a bridging plate. Direct comparisons of a fibula flap and an anterolateral thigh flap, the applicability between a reconstruction plate and miniplate, and the correlation between plate-related complications and quality of life remain unclarified. Therefore, this study aimed to the explore complications of different flaps and plates and how they impact the patients' quality of life.

METHODS

We retrospectively reviewed the medical records of a total of 205 patients aged >18 years who underwent segmental mandibulectomy and reconstruction using fibula flap with reconstruction plate (FR; n = 86), fibula flap with miniplate (FM; n = 61), and anterolateral thigh flap with reconstruction plate (AR; n = 58) due to cancer ablation, osteoradionecrosis, or benign tumor excision between August 2010 and December 2019. Data on characteristics, complications, and health-related quality of life were collected and analyzed.

RESULTS

The plate-related complication rate was the highest in the AR group (37.9%), then in the FR group (25.6%), and was the lowest in the FM group (13.1%; p = 0.0079). The plate exposure rate was the highest in the AR group (24.1%), then in the FR group (15.7%), and was the lowest in the FM group (4.9%; p = 0.0128). The plate fracture and dislodge rates for the AR group were both higher than those for the FR and FM groups (24.1% versus 9.3% versus 9.8%, respectively; p = 0.023). The AR group had worse complication-free survival (hazard ratio [HR]: 3.61, 95% CI: 1.99-6.56, and p < 0.0001) than the FR and FM groups. Osteoradionecrosis (HR: 6.19, 95% CI: 2.11-18.21, and p = 0.0009) and postoperative radiotherapy (HR: 2.87, 95% CI: 1.34-6.12, and p = 0.0402) were both independent adverse factors for complication-free survival, whereas patient treated primarily (HR: 0.35, 95% CI: 0.17-0.73, and p = 0.0048) was an independent protective factor. Plate-related complication negatively impacted the quality of life based on pain scores (β: -0.56, SE: 0.26, and p = 0.034).

CONCLUSIONS

Using a fibular flap fixed with miniplates and avoiding the use of a reconstruction plate may yield a reduced plate exposure rate and better health-related quality of life, particularly for patients with osteoradionecrosis or those who need postoperative radiotherapy.

Risk factors associated with fixation-related complications in microsurgical free flap reconstruction of the mandible

BACKGROUND

Hardware complications (loosening of screws, infection, or exposure of the plate) in mandibular reconstruction with vascularized osseous free flaps impose significant morbidity, and frequently require revision surgery. Purpose of this study was to identify possible contributing factors for hardware complications.

METHODS

This is a retrospective cohort study involving case series of patients who underwent microvascular mandible reconstructions between 2000 and 2020. Patient demographics, pathological, clinical, and treatment-related factors were analyzed in univariate and multivariate analyses.

RESULTS

Ninety-one patients were enrolled, encompassing 63 reconstructions with fibular free flaps, 26 reconstructions with scapular, and 2 reconstructions with iliac flaps. Rate of hardware complications and plate exposure was 14.3% and 7.7%, respectively, with a median follow-up time for extrusion of 29 months. In univariate analysis, preoperative radiotherapy (odds ratio [OR] = 6.57, p = .01), and secondary mandible reconstruction (OR = 4.3, p = .04) were significant predictors of hardware complications, and plate exposure was most frequently found in secondary reconstruction (37.5%, OR = 11.8, p = .04). Hypertension was the most commonly found comorbidity (24%), and it trended toward significance regarding plate exposure (p = .05). Only secondary mandible reconstruction was associated with osteosynthesis complications (OR = 12.53, p = .01) and plate exposure (OR = 23.86, p = .005) on multivariate analysis, while preoperative radiation therapy did not retain its relevance on plate exposure.

CONCLUSION

Secondary mandible reconstructions with vascularized osseous free flaps have a higher risk of osteosynthesis complications than primary reconstructions.

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.

Osseous Union after Mandible Reconstruction with Fibula Free Flap Using Manually Bent Plates vs. Patient-Specific Implants: A Retrospective Analysis of 89 Patients

The aim of this monocentric, retrospective clinical study was to evaluate the status of osseous union in uni- and poly-segmental mandible reconstructions regarding conventional angle-stable manually bent osteosynthesis plates (Unilock 2.0 mm) versus titan laser-melted PSI patient-specific implant’s (PSI). The clinical impact of PSI’s high stiffness fixation methods on bone healing and regeneration is still not well addressed. The special interest was in evaluating the ossification of junctions between mandible and fibula and between osteotomized fibula free flap (FFF) segments. Panoramic radiograph (OPT), computed tomography (CT) scans, or cone-beam CTs (CBCT) of patients who underwent successful FFF for mandible reconstruction from January 2005 to December 2020 were analyzed. A total number of 89 cases (28 females (31.5%), 61 males (68.5%), mean age 58.2 ± 11.3 years, range: 22.8–82.7 years) fulfilled the chosen inclusion criteria for analysis (conventional: n = 44 vs. PSI: n = 45). The present study found an overall incomplete ossification (IOU) rate of 24.7% (conventional: 13.6% vs. PSI: 35.6%; p = 0.017) for mandible to fibula and intersegmental junctions. Between osteotomized FFF segments, an IOU rate of 16% was found in the PSI-group, while no IOU was recorded in the conventional group (p = 0.015). Significant differences were registered for IOU rates in poly-segmental (p = 0.041), and lateral (p = 0.016) mandibular reconstructions when PSI was used. Multivariate logistic regression analysis identified plate exposure and type of plate used as independent risk factors for IOU. Previous or adjuvant radiotherapy did not impact incomplete osseous union in the evaluated study sample. PSI is more rigid than bent mini-plates and shields functional mechanical stimuli, and is the main reason for increasing the rate of incomplete ossification. To enhance the functional stimulus for ossification it has to be discussed if patient-specific implants can be designed to be thinner, and should be divided into segmental plates. This directs chewing forces through the bone and improves physiological bone remodeling.

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.

Patient-Specific 3D-Printed Miniplates for Free Flap Fixation at the Mandible: A Feasibility Study

Background

This study was conducted to evaluate the feasibility, clinical outcomes, and accuracy of patient-specific 3D-printed miniplates for mandible reconstruction with fibula free flaps.

Methods

A feasibility study was conducted with 8 patients. Following virtual planning, patient-specific 1.0 mm titanium non-locking miniplates were produced via laser selective melting. 3D-printed cutting and drilling guides were used for segmental mandible resection and flap harvesting. Flap fixation was performed with two 4-hole miniplates and 2.0 mm non-locking screws (screw length 7 mm) for each intersegmental gap. Clinical follow-up was at least 6 months. Preoperative and postoperative CT/cone beam CT data were used for 3D accuracy analysis and evaluation of bone healing. Plate-related complications were monitored clinically.

Results

Patient-specific miniplate fixation of all flaps was successfully conducted (4 mono-segmental, 4 dual-segmental) with high accuracy (3.64 ± 1.18 mm) between the virtual plan and postoperative result. No technical complications were encountered intraoperatively. Osseous union occurred in all intersegmental gaps (1 partial, 18 complete) after 10 ± 2 months. No material fracture, dislocation, or plate exposure was observed.

Conclusions

Based on this pilot observational study including a limited number of patients, free flap fixation for mandibular reconstruction with patient-specific 3D-printed miniplates is feasible and associated with high accuracy, bone healing, and remote soft tissue complications.

Reconstruction of the mandibular symphysis: pilot study compares three different flaps

BACKGROUND

Restoration of mandibular continuity, functionality and attempting to return patients to their premorbid state is the ultimate goal of reconstruction. Some studies compare different flaps but the reconstructed portions vary and there is little consensus on the best option for a particular defect.

METHODS

This pilot study compares three different reconstructive options with free flap. We will analyze the accuracy of the reconstruction, the post-operative complications related to the reconstruction, the morbidity of the donor site. This pilot study compares three different reconstructive options with free flap in the reconstruction of the mandibular symphysis: iliac crest, scapula and fibula.

RESULTS

In our sample the morbidity of the donor site was overlapping, as for all three choices free from complications. In post resection edentulous patients, the fibula seems to guarantee better positioning, while in patients with residual occlusion the iliac crest (figure n.4 and n.5) seems to allow a more congruous repositioning. The fibula seems to have a superiority over the other flaps in terms of accuracy in all types of patient.

CONCLUSIONS

Contrary to the most recent work on the accuracy of CAD / CAM, we have analyzed the error in the reconstruction of a specific segment and in the repositioning of the residual mandibular component without the use of guided computer programming.

Thirty-eight-year follow-up of the first patient of mandibular reconstruction with free vascularized fibula flap

BACKGROUND

The mandible is responsible for vital functions of the stomatognathic system, and its loss results in functional and aesthetic impairment. Mandibular reconstruction with free fibula flap is considered the gold standard for mandibular reconstruction.

CASE PRESENTATION

We describe here the 38-year follow-up of the patient who was the first case of mandibular reconstruction with free fibula flap reported in the literature. The original report describes a 27-year-old woman who had undergone extensive mandibulectomy due to an osteosarcoma. A microvascularized fibula flap was used for mandibular reconstruction in 1983. Two years later, a vestibulo-lingual sulcoplasty with skin graft was performed to allow the construction of a total dental prosthesis. Fifteen years after the initial treatment, an autologous iliac crest graft was placed in the fibula flap, aimed at increasing bone thickness and height for rehabilitation with implant supported prosthesis. In 2015, a rib graft was positioned in the mental region, enhancing the support to the soft tissues of the face and improving the oral function. A recent review of the patient shows well-balanced facial morphology and optimal functional results of the procedure.

CONCLUSIONS

The fibula flap method, described in 1975 and first reported for mandibular reconstruction in 1985, continues to be applied as originally described, especially where soft tissue damage is not extensive. Its use in reconstructive surgery was expanded by advancements in surgery and techniques such as virtual surgical planning. However, there is still a lack of evidence related to the long-term evaluation of outcomes. The present work represents the longest-term follow-up of a patient undergoing mandibular reconstruction with free vascularized fibula flap, presenting results showing that, even after 38 years, the procedure continues to provide excellent results.

Removal of patient-specific reconstruction plates after mandible reconstruction with a fibula free flap: is the plate the problem?

Computer-aided microvascular mandible reconstruction is an increasingly common procedure in oral and maxillofacial surgery. The aim of this retrospective single-centre study was to evaluate the rate and specifics of hardware removal after fibula free flap (FFF) fixation with a patient-specific reconstruction plate. The study included patients who underwent hardware removal between April 2017 and October 2019. Statistical analyses were performed regarding the different indications for plate removal (dental implantation versus complication) and the surgical approach (intraoral versus extraoral). Plate removal was performed in 29 of 98 patients (29.6%) after FFF fixation with a patient-specific reconstruction plate. Plate removal was done prior to dental implantation in 58.6% of cases and due to complications in 41.4%. Complications seen between reconstructive surgery and plate removal were less frequent in the dental rehabilitation group (8/17 vs 12/12; P=0.002). Within this group, 35.3% of plates were removed intraorally, and the majority of partial plate removals were performed in the patients with plate removal for dental rehabilitation (72.7% vs 27.3%). Hospitalization was shorter with an intraoral approach (1.7 days vs 4.0 days, P=0.052). The removal of patient-specific reconstruction plates prior to dental implantation is often partial and can be performed intraorally. The use of patient-specific miniplates for fixation of FFF might facilitate later dental rehabilitation.

Fibula Graft Cutting Devices: Are 3D-Printed Cutting Guides More Precise than a Universal, Reusable Osteotomy Jig?

Individual cutting guides for the reconstruction of lower jaw defects with fibular grafts are often used. However, the application of these osteotomy tools is costly and time intensive. The aim of this study was to compare the precision of osteotomies using a 3D-printed guide with those using a universal, reusable, and more cost-efficient Multi-Use Cutting Jig (MUC-Jig). In this non-blinded experimental study, 10 cranio-maxillofacial surgeons performed four graft removals each in a randomized order using the same osteotomy angle, both proximally (sagittal cut) and distally (coronal cut), of a graft (45°, 30°, 15°, or 0°), first with the MUC-Jig then with the 3D-printed cutting guide. The 40 fibula transplants (Tx) of each method (n = 80) were then analyzed concerning their Tx length and osteotomy angles and compared to the original planning data. Furthermore, the surgeons’ subjective perception and the duration of the two procedures were analyzed. The mean relative length and mean relative angle deviation between the MUC-Jig (−0.08 ± 1.12 mm; −0.69° ± 3.15°) and the template (0.22 ± 0.90 mm; 0.36° ± 2.56°) group differed significantly (p = 0.002; p = < 0.001), but the absolute deviations did not (p = 0.206; p = 0.980). Consequently, clinically comparable osteotomy results can be achieved with both methods, but from an economic point of view the MUC-Jig is a more cost-efficient solution.

Rapid prototyping: applications in oral and maxillofacial surgery

This article documents four mandibular reconstructions performed using free fibula flaps. CT scan DICOM (Digital Imaging and COmmunication in Medicine) files were obtained in order to print stereolithographic models of the mandible, and in one case cutting guides for fibular osteotomies. One case study details the treatment a cancer recurrence on a right emimandibulectomy. Because of a lack of access to previous CT scans, the left part of the mandible was mirrored to obtain an accurate 3D model. In one case, due to the young age of the woman, a double barrel fibula flap was used. All cases resulted in satisfactory chewing function and aesthetic outcome, with no flap failures. The report concludes that Virtual Planning and Rapid Prototyping are helpful as they reduce costs and intraoperative times while simultaneously improving surgical precision.

Complication of osteo reconstruction by utilizing free vascularized fibular bone graft

The success of free vascularized fibular bone graft (FVFBG) has accelerated the osteo reconstruction which results from trauma, resection of a tumor or an infectious bone segment, or correction of congenital deformity. But the complication behind should not be overlooked. The failure could necessitate a second surgery, which prolong the rehabilitation period and produce further health cost. Worst, the patients may suffer a permanent impaired ankle function, or a sustained morpho-functional loss on reconstructive area which are hard to save. To provide an overview of the complication related to reconstruction by FVFBG, a narrative review is conducted to identify the complications including their types and rates, the contributing factors, the approaches to measure and the techniques to avoid. Methodologically, by quick research on Pubmed and abstract reading of reviews, we characterize five reconstructive areas where FVFBG were most frequently applied: extremities, mandible, spine, osteonecrosis of femoral head, and penile. Following, the complications on different reconstructive areas are retrieved, studied and presented in five (or more specifically, six) separate sections. By the way, meaningful difference between FVFBG and other bone flap was presented in a few words if necessary. Donor-site morbidities were studied and summarized as a whole. In these literatures, the evidences documented on limb and mandibular reconstruction have the fullest detail, followed by the spine and lastly the penile. In conclusion, FVFBG, though a mature technique, needs further deep and comprehensive study and maybe device-based assistance to achieve better reconstructive effect and minimize donor-site damage.