Technique For Mandibular Reconstruction Research Articles

Uncovering the unique characteristics of the mandible to improve clinical approaches to mandibular regeneration.

The mandible (lower jaw) bone is aesthetically responsible for shaping the lower face, physiologically in charge of the masticatory movements, and phonetically accountable for the articulation of different phonemes. Thus, pathologies that result in great damage to the mandible severely impact the lives of patients. Mandibular reconstruction techniques are mainly based on the use of flaps, most notably free vascularized fibula flaps. However, the mandible is a craniofacial bone with unique characteristics. Its morphogenesis, morphology, physiology, biomechanics, genetic profile, and osteoimmune environment are different from any other non-craniofacial bone. This fact is especially important to consider during mandibular reconstruction, as all these differences result in unique clinical traits of the mandible that can impact the results of jaw reconstructions. Furthermore, overall changes in the mandible and the flap post-reconstruction may be dissimilar, and the replacement process of the bone graft tissue during healing can take years, which in some cases can result in postsurgical complications. Therefore, the present review highlights the uniqueness of the jaw and how this factor can influence the outcome of its reconstruction while using an exemplary clinical case of pseudoarthrosis in a free vascularized fibula flap.

Severely resorbed mandible treatment: a 12-years follow-up case report

Rehabilitation of severely atrophic jaws has been a major problem for elderly patients and dentists. When conventional rehabilitation treatments are not possible, bone intervention is deemed necessary. Mandibles with less than 12 millimeters (mm) in height imply insufficient retention of the prosthesis, intolerance to mucosal load, pain and, consequently, incapacity of oral functions and decreased facial aesthetics. Endosseous implants are a widely accepted therapy for SRM rehabilitation, but it depends on the amount of bone available for a good prognosis. The Tent Pole technique is based on the addition of bone graft and expansion of the soft tissue matrix, mainly for cases of SRM with 6 mm or less of bone height available for rehabilitative treatments with endosseous dental implants. The objective of this report is to present and update a previously published clinical case of SRM reconstruction and rehabilitation using the tent pole technique, with 12 years of follow-up. The female patient, who underwent treatment at 63 years of age, received treatment using the Tent Pole surgical technique for mandibular reconstruction with cranial autogenous particulate bone graft. The treatment was favorable during the 12 years of control, the CT scan showed that the grafted bone was stable in volume and the mandible was enlarged in three dimensions.

Mandibular Reconstruction With Fibula Flap and Dental Implants Through Virtual Surgical Planning and Three Different Techniques: Double-Barrel Flap, Implant Dynamic Navigation and CAD/CAM Mesh With Iliac Crest Graft.

IntroductionVertical discrepancy between the fibula flap and the native mandible results in difficult prosthetic rehabilitation. The aim of this study was to evaluate the outcomes of 3D reconstruction of the mandible in oncologic patients using three different techniques through virtual surgical planning (VSP), cutting guides, customized titanium mesh and plates with CAD/CAM technology, STL models and intraoperative dynamic navigation for implant placement. Material and methodsMaterial and MethodsThree different techniques for mandibular reconstruction and implant rehabilitation were performed in 14 oncologic patients. Five patients (36%) underwent VSP, cutting guides, STL models and a customized double-barrel titanium plate with a double-barrel flap and immediate implants. In six patients (43%), VSP, STL models and a custom-made titanium mesh (CAD/CAM) for 3D reconstruction with iliac crest graft over a fibula flap with deferred dental implants were performed. Three patients (21%) underwent VSP with cutting guides and customized titanium plates for mandibular reconstruction and implant rehabilitation using intraoperative dynamic navigation was accomplished. Vertical bone reconstruction, peri-implant bone resorption, implant success rate, effects of radiotherapy in vertical reconstruction, bone resorption and implant failure, mastication, aesthetic result and dysphagia were evaluated.ResultsSignificant differences in bone growth between the double-barrel technique and iliac crest graft with titanium mesh technique were found (p<0.002). Regarding bone resorption, there were no significant differences between the techniques (p=0.11). 60 implants were placed with an osseointegration rate of 91.49%. Five implants were lost during the osseointegration period (8%). Peri-implant bone resorption was measured with a mean of 1.27 mm. There was no significant difference between the vertical gain technique used and implant survival (p>0.385). Implant survival rates were higher in non-irradiated patients (p<0.017). All patients were rehabilitated with a fixed implant-supported prosthesis reporting a regular diet (80%), normal swallowing (85.7%) and excellent aesthetic results.ConclusionsMulti-stage implementation of VSP, STL models and cutting guides, CAD/CAM technology, customized plates and in-house dynamic implant navigation for mandibular defects increases bone-to-bone contact, resolves vertical discrepancy and improves operative efficiency with reduced complication rates and minimal bone resorption. It provides accurate reconstruction that optimizes implant placement, thereby improving facial symmetry, aesthetics and function.

Computer-assisted resection of mandibular cancer and repair with fibula free flap. Case report

Oral cancer is a disease, in the treatment of which the surgical resection of the lesion plays a lead- ing role. Oncological resections in the maxillofacial area create large deficits that affect the functionality and aesthetics of the patient to a large extent, while many times make oncological resection impossible due to their inability to restore. The mandibular deficits are particularly difficult, with the free osteocutaneous fibular flap being the gold standard in repairing large mandibular deficits. In recent years, technology has offered significant as- sistance in the successful restoration of functional and aesthetic disorders through the virtual planning of the operation. In this paper we present a case of oral cancer whose resection and reconstruction with fibula free flap were done after digital design and under the guidance of special cutting guides. To our knowledge, this case of computer-guided reconstruction with FFF represents the first description of such a technique for mandibular reconstruction in the available greek medico-dental literature.

Computer-assisted versus traditional freehand technique for mandibular reconstruction with free vascularized fibular flap: A matched-pair study

This study aimed to perform a surgery-related and patient-related outcome analysis of a case-matched series of patients treated with computer-assisted surgery (CAS) and traditional freehand surgery. A total of 153 patients who underwent mandibular reconstruction by VFF were included from Jan 1999 to Dec 2019. The mandibular resection and reconstruction were performed by four experienced oral and maxillofacial surgeons. Reasons for reconstruction were oncologic, osteoradionecrosis, trauma, and osteoporosis. All the patients were followed up postoperatively for at least 1 year. Eighteen pairs were formed with the matched cohort consisting of a total of 36 patients who underwent primary mandibular reconstruction without additional combined flaps. The surgery-related and patient-related continuous and categorical parameters were assessed in both groups. The average operation time and bleeding volume in the CAS group were less than those in the non-CAS group. Additionally, both hospitalization and ICU days were lower in the CAS group without any significant difference. The only significant finding related to surgical parameters was observed for the ischemia time, which was lower in the CAS group. Computer-assisted surgery indicated improved efficiency considering reduced ischemia time, operation time, and length of hospital stay with lower early complications than that of conventional surgical procedures. It can thus be considered as an optimized alternative to the freehand approach.

An innovative tool for mandibular reconstruction in oral malignancies: A pictorial essay

Mandibular reconstruction is challenging for most head and neck surgeons. Technological advances have led to the development of a new innovative procedure based on the concepts of computer-assisted design (CAD) and virtual surgical planning (VSP). The main disadvantage of this technique is the lack of flexibility, especially in oncology. A possible solution is the development of a semi-standardized mandible and fibula resection cutting guide: the L1® mandible ReconGuide.We provided a step-by-step description of the operative technique for mandibular reconstruction with the L1® mandible ReconGuide. The L1® mandible ReconGuide is a guiding force toward mandibular reconstruction. Moreover, the tool has been designed to suit the needs of the patients, particularly those with oral cancer, thereby permitting intraoperative planning and increasing time and cost effectiveness.In this pictorial essay, we have presented the operative techniques of using the L1® mandible ReconGuide for reconstruction.

The Sydney Modified Alberta Reconstruction Technique (SM-ART) for dental rehabilitation following mandibulectomy or maxillectomy

The Sydney Modification of the Alberta Mandibular Reconstruction technique (SM-ART) is a hybrid of the Rohner method and the Alberta Reconstructive Technique (ART). SM-ART differs from ART in three ways, notably the use of custom plates, intraoral placement of implants via three-dimensionally printed guides and a skin graft buried deep into the skin paddle of the fibula flap in the first stage of the reconstruction.

Patient-specific alloplastic endoprosthesis for reconstruction of the mandible following segmental resection: A case series

Reconstruction of mandibular discontinuity defects remains a challenge for maxillofacial surgeons. Despite vascularized free flaps representing the current gold standard for managing such defects, the search continues for other less morbid yet predictable interventions. This study aimed at reviving the idea of alloplastic mandibular endoprosthesis as a treatment modality for reconstruction of segmental mandibular defects following eradication of benign tumors.To reconstruct their segmental mandibular defects, this case series compiled seven patients who received patient-specific titanium implant (PSI) with osseointegrated components and were designed to receive a restoration for dental rehabilitation. The recruited patient population was followed-up for a period of 3–5 years. Three of the seven PSIs failed due to extensive intraoral mucosal dehiscence or persistent extraoral fistulae. Patients with the 4 surviving PSIs enjoyed good results in terms of occlusion, masticatory function, mouth opening as well as pleasing facial esthetics.The described technique represents a viable less morbid alternative to the standard bone grafting techniques for mandibular reconstruction in carefully selected patients. Further studies are needed to modify the PSI design and surface treatment for better outcomes.

CAD-CAM vs conventional technique for mandibular reconstruction with free fibula flap: A comparison of outcomes

IntroductionMandibular reconstruction always pose a challenge to the reconstructive surgeon. With the use of Computer aided designing and computer aided manufacturing (CAD-CAM) it is now possible to reconstruct mandibular defects to near normal configuration with good function and aesthetic outcomes. Aims/objectivesTo compare the efficacy of CAD-CAM technique vs conventional technique in mandibular reconstruction with free fibula flap. Materials and methods40 consecutive patients that required mandibular reconstruction using free fibula flap were included in the study. All patients were treated using CAD-CAM technique and then compared retrospectively with 40 patients treated with conventional technique. Comparison was done between total intraoperative time, aesthetic outcome and post-operative occlusion. ResultsTotal intraoperative time in the CAD-CAM group was significantly reduced (562 min) as compared to the conventional group (662 min). Patients in the CAD-CAM group also obtained a better Aesthetic score (3.6/5) when compared to the conventional group (2.5/5). Postoperative malocclusion was noted in 1 patient in the CAD-CAM group as opposed to 6 patients in the conventional group. ConclusionUse of CAD-CAM technology in mandibular reconstruction with free fibula flap offers reduced surgical time with precise and accurate reconstruction that produces better functional and aesthetic outcomes.

Mandibular Reconstruction With a Deep Circumflex Iliac Artery Flap Using Computer-Assisted and Intraoral Anastomosis Techniques

This study aimed to evaluate intraoral anastomosis of a deep circumflex iliac artery (DCIA) flap in combination with computer-assisted techniques for mandibular reconstruction. Between December 2015 and March 2018, 4 patients with mandibular discontinuity defects caused by ablative tumor surgery were included in the study. Mandibular reconstruction was performed with a DCIA flap using computer-assisted and intraoral anastomosis techniques. A computer-aided design-computer-aided manufacturing cutting guide, a reconstruction stereomodel, and a prebent reconstruction plate were used for mandibular reconstruction in each patient.Anastomosis was performed on the facial artery and vein using the deep circumflex iliac vessels through an intraoral approach. The resulting error-grade color map was used to evaluate repeatability between the preoperative design and postoperative results. Mandibular reconstruction with a DCIA flap using computer-assisted and intraoral anastomosis techniques was successful in all 4 patients. All flaps survived with no severe complications. Satisfactory cosmetic outcomes and occlusion with sufficient bone height for implants were achieved postoperatively. Repeatability between the virtual plan and postoperative result was 81.1%±8.2% within 1mm, 85.8%±8.1% within 2mm, and 89.6%±6.7% within 3mm. The use of intraoral anastomosis and computer-assisted techniques with DCIA flaps for mandibular reconstruction without additional facial scarring is feasible and advantageous. However, the findings should be interpreted cautiously owing to the relatively short follow-up time and limited number of patients involved in this study.

Mandibular reconstruction

Mandibular reconstruction presents unique functional and aesthetic challenges to the reconstructive surgeon. This review will cover current techniques for mandibular reconstruction, including the various plating strategies for rigid fixation, the choice of osseous donor site, and the concurrent reconstruction of associated soft tissue defects. Recent developments and future horizons in mandibular reconstruction including the use of virtual surgical planning and tissue engineering will also be addressed.

Current Therapeutic Options for Implant-Supported Rehabilitation of Severely Atrophic Mandibles

The implant-supported rehabilitation of atrophic mandibles (AM) with severe bone resorption is challenging for both surgical and prosthetic procedures due to the high risk of mandible fracture during implant surgery and postoperatively due to the masticatory load. The aim of case presentations was to demonstrate treatment alternatives for patients with AM who required oral rehabilitation with osseointegrated implants (OIs) according to the residual mandibular bone volume. When bone is 9 mm in height, the ideal treatment is the use of narrow, short OIs. When the bone height is 5 to &lt; 9 mm, mandibular reinforcement with reconstruction plates using the intraoral approach and simultaneous placement of osseointegrated implants are proposed. In cases where bone height is &lt; 5 mm, the choice of treatment is mandibular reconstructive surgery with an autogenous bone graft and biomaterials. The fundamental principles of this protocol are to reduce the morbidity and complications associated with the surgical procedure, which would reduce both the time and cost of full dental rehabilitation. The choice of the technique for mandibular reconstruction should be indicated according to the magnitude of the atrophy.

Reconstruction of Mandible: A Fully Digital Workflow From Visualized Iliac Bone Grafting to Implant Restoration

Although digital aids can help surgeons compensate for the shortcomings of traditional mandibular reconstruction techniques to perform surgery more precisely and effectively, the use of these digital techniques has often been fragmented, divided, and incomplete. This article describes the workflow of a fully digital mandibular reconstruction to explore the proper indications and discusses innovations based on the accuracy and effectiveness of digital techniques. A restoration-oriented mandibular reconstruction was performed by applying different digital techniques. Preoperative virtual surgery and rapid prototyping were used to aid the vascularized iliac bone graft surgery, which offered a solid basis for the ensuing treatment. Subsequently, implant rehabilitation was accomplished with the assistance of computer-assisted design and manufacture, laser treatment, and selective laser melting techniques. The workflow of the fully digital mandibular reconstruction successfully achieved a restoration-oriented treatment. These predictable, accurate, and effective digital techniques improved the consistency of pretreatment design and follow-up treatment. The treatment sequence achieved high predictability and reproducibility owing to the use of digital techniques. This study shows that a digital workflow can be predictable, accurate, and effective, which suggests that it could be a valid digital protocol for developing a treatment sequence for patients with jaw defects caused by trauma, congenital anomalies, or mandibular tumor resection.

Evolution of surgical techniques for mandibular reconstruction using free fibula flaps: The next generation.

Virtual surgical planning (VSP) has contributed to a number of technical innovations in mandible reconstruction. We report on these innovations and the overall evolution of mandible reconstruction using free fibula flaps at our institution. We performed a retrospective chart review of all patients who underwent virtually planned free fibula flap reconstruction of the mandible. Comparisons were made between cohorts based on distinct eras related to the virtual planning approach. Seventy-six patients underwent a total of 78 VSP-assisted mandible reconstructions with free fibula flaps. Significant differences were noted among the groups with regard to mean number of segments, percentage of flaps that had at least 3 segments, percentage of flaps that had double-barrel components, and innovations per flap. VSP-assisted mandible reconstruction has contributed to more complex surgeries at our institution. The technology ensures functional restoration, permitting an optimized aesthetic reconstruction that has not increased operative times or complications. © 2016 Wiley Periodicals, Inc. Head Neck 38: E2066-E2073, 2016.

Up-and-Coming Mandibular Reconstruction Technique With Autologous Human Bone Marrow Stem Cells and Iliac Bone Graft in Patients With Large Bony Defect

Large bony defects followed by resection of the mandible need to be reconstructed by various surgical techniques such as the fibular flap. In this article, we report the case of mandibular reconstruction with autologous human bone marrow mesenchymal stem cells and autogenous bone graft, followed by placement of dental implants and prosthodontic treatment in a patient who has been failed to reconstruct mandibular bone defect after resection of mandible.

To Computer-Aided Design and Manufacturing or Not to Computer-Aided Design and Manufacturing? Free Fibula Flap With Computer-Aided Technique for Mandibular Reconstruction

The purpose of this study was to analyze the accuracy of computer-assisted free fibula flap for reconstruction of large mandibular defects for benign tumors. Between December 2012 and January 2014, a total of 4 free osteocutaneous computer-assisted fibula flaps have been used in an equal number of patients for reconstruction of the mandible at the Division of Maxillofacial Surgery, Città della Scienza e della Salute Hospital, University of Turin. Inclusion criteria were large mandibular defects due to benign tumors. The computer-assisted fibula flap was chosen when 2 or more osteotomies were requested. Intraoperative complication, mean ischemia time, operative time, and morphologic outcomes were analyzed in all cases. After surgery, a postoperative computed tomography compared the virtual plan with the surgical results. All 3 flaps were harvested and transplanted successfully. For the free flaps examined in this work, no intraoperative complications were noted. Postoperative computed tomography showed high correspondence in terms of bone contour according to the virtual plan. The immediate and long-term morphologic results were satisfactory. Microsurgical mandible reconstruction using a computer-assisted fibula flap technique is the best available method to manage complex defects.

Axially vascularised mandibular constructs: Is it time for a clinical trial?

Applying regenerative therapies in the field of cranio-maxillofacial reconstruction has now become a daily practice. However, regeneration of challenging or irradiated bone defects following head and neck cancer is still far beyond clinical application. As the key factor for sound regeneration is the development of an adequate vascular supply for the construct, the current modalities using extrinsic vascularization are incapable of regenerating such complex defects. Our group has recently introduced the intrinsic axial vascularization technique to regenerate mandibular defects using the arteriovenous loop (AVL). The technique has shown promising results in terms of efficient vascularization and bone regeneration at the preclinical level.In this article, we have conducted a narrative literature review about using the AVL to vascularize tissue-engineering constructs at the preclinical level. We have also conducted a systematic literature review about applying the technique of axial vascularization in the field of craniofacial regeneration.The versatility of the technique and the possible challenges are discussed, and a suggested protocol for the first clinical trial applying the AVL technique for mandibular reconstruction is also presented.

Hybrid mandibular reconstruction technique: Preliminary case series of prosthetically-driven vascularized fibula free flap combined with tissue engineering and virtual surgical planning

Hybrid mandibular reconstruction technique: Preliminary case series of prosthetically-driven vascularized fibula free flap combined with tissue engineering and virtual surgical planning

Computer-Aided Mandibular Reconstruction With Vascularized Iliac Crest Bone Flap and Simultaneous Implant Surgery.

The intention of oral rehabilitation in patients with mandibular defects is an early prosthetic treatment with maximum possible functionality and high accuracy. The present study describes a new computer-aided technique for mandibular reconstruction using a free vascularized iliac flap and simultaneous insertion of dental implants into the flap while it is still pedicled at the donor site. Based on preoperative computerized tomography data of the facial skeleton and the iliac crest donor site, a surgical guide transferred the virtual plan including information on the transplant dimensions and shape as well as the position of the dental implants into real-time surgery. Using postoperative computerized tomography scans, the actual situation were compared with the preoperative simulation. A mean difference of 0.75 mm (SD ± 0.72) for the flap shape and 0.70 mm (SD ± 0.44) for the implant position analysis was determined. A calculation of the closest point distance showed a surface deviation of <2 mm for the shape analysis in 93.3% of the values and <1 mm for implant position in 75.2% of the values. The mean angular deviation was 3.65°. Virtual surgical planning is a suitable method for mandibular reconstruction with vascularized iliac crest flaps and simultaneous implant surgery. It can be used to restore the anatomy of the mandible with a high accuracy and can help to shorten subsequent dental rehabilitation.

Step-by-step surgical technique for mandibular reconstruction with fibular free flap: application of digital technology in virtual surgical planning.

At present, mandibular reconstruction with a fibular free flap is the gold standard for functional and esthetic rehabilitation after oncological surgery. The purpose of this study was to describe the computer-assisted mandibular reconstruction procedure adopting the customized solution Synthes ProPlan CMF. The study reports five consecutive patients with benign or malignant disease requiring mandibular reconstruction using a microvascular fibular free flap, pre-operative virtual planning, construction of cutting guides and customized laser pre-bent titanium plates. The surgical technique is discussed in a step-by-step fashion. The average post-operative hospital stay was 18 ± 3 days. Ischemia time was recorded in all five cases, with an average of 75 ± 8 min. No problems were encountered in any surgical step and there were no major complications. Excellent precision of cutting guides and a good fit of pre-bent plates were found on both the mandible and fibula. There was excellent precision in bone to bone contact and position between mandible and fibula graft. Measurement data from the pre-operative and post-operative CT scans were compared. The average difference (Δ) between programed segment lengths and CT control segment lengths was 0.098 ± 0.077 cm. Microsurgical mandibular reconstruction using a virtual surgical planning yields significantly shorter ischemia times and allows more precise osteotomies. The technology is becoming increasingly recognized for its ability to optimize surgical outcomes and minimize operating time. Considering that the extent of resection can be wider than predicted, this results in safer modeling of the fibula only after frozen sections have demonstrated the radicality of resection.