Maxillofacial Reconstruction Research Articles

Bone remodeling following mandibular reconstruction using fibula free flap

To investigate bone remodelling responses to mandibulectomy, a joint external and internal remodelling algorithm is developed here by incorporating patient-specific longitudinal data. The primary aim of this study is to simulate bone remodelling activity in the conjunction region with a fibula free flap (FFF) reconstruction by correlating with a 28-month clinical follow-up. The secondary goal of this study is to compare the long-term outcomes of different designs of fixation plate with specific screw positioning. The results indicated that the overall bone density decreased over time, except for the Docking Site (namely DS1, a region of interest in mandibular symphysis with the conjunction of the bone union), in which the decrease of bone density ceased later and was followed by bone apposition. A negligible influence on bone remodeling outcome was found for different screw positioning. This study is believed to be the first of its kind for computationally simulating the bone turn-over process after FFF maxillofacial reconstruction by correlating with patient-specific follow-up.

Mandibular Reconstruction with Iliac Crest Graft Associated with L-PRF and Hyperbaric Oxygen Therapy: A Case Report

Maxillofacial reconstructions with free grafts have become a routine reality for plastic surgeons and maxillofacial surgeons in the last decade. This condition usually occurs after radical treatment of benign or malignant pathologies of the stomatognathic complex, through en bloc resections with a safety margin to reduce the chances of recurrence of the pathology. One of the great challenges faced by surgical teams is no longer just in relation to the technique used for planning, but the predictability and maintenance of the graft performed in the face of systemic changes that can compromise the success of the graft, such as diabetes mellitus. Several aspects have been explored in recent years, such as the use of ozone, synthetic membranes, formation of Leukocyte and Platelet Rich Fibrin (L-PRF) and hyperbaric therapy in the quest to maximize the chances of graft success, reducing the chances of infection and bone resorption mainly through osteoinductive and osteogenic stimuli, which are not characteristics present in a metabolic dysfunction such as diabetes. Another important data for these types of surgery is the bone quality offered by the donor bed, because in maxillofacial reconstructions, a balance in the amount of corticalized bone and medullary bone is important, which leads us to characteristics such as the best donor bed for these surgical reconstructions in the iliac crest region. Here the authors present a case of 64 years old male hypertensive patient with h/o diabetes mellitus, managed by a mandibular reconstruction surgery with iliac crest graft associated with L-PRF and hyperbaric oxygen therapy after extensive resection of a benign mandibular tumour in a patient with diabetes mellitus.

Virtual Surgical Planning and Pre-operative Simulation for Maxillofacial Reconstruction with 3D Printing Technology in Tumor-affected Facial Deformity

Background: The high anatomical complexity of maxillofacial defects caused by tumor can pose a formidable challenge for clinicians when designing an appropriate plan for surgical reconstruction. The intention of this work was to restore the complex anatomy with maximum possible facial functionality and aesthetics of the patient. Based on the medical images generated by Computed Tomography (CT) scan an optimal therapeutic planning for complex maxillofacial reconstruction was designed.

Technical Note on the production of 3D anatomical models using an open access software from medical imaging

Introduction: 3D modelling and intra-operative guides are rapidly increasing in use. They have been shown in meta-analyses to increase surgical accuracy, reduce operative time and improve teaching(1, 2). Despite the growing availability of 3D printers, access to 3D models and intra-operative guides is limited by the cost and availability of software and engineers. Methods: This technical note shows how to use 3Dslicer, a free open source multiplatform software available to download from the internet. It can be used to create 3D models from medical imaging such as CT and MRI. Results: 3D objects can be manipulated digitally or printed using 3D printers. They can be used to aid teaching, surgical planning and patient demonstrations. Conclusions: 3Dslicer is an easy to use software which should be in the surgeon's armamentarium. Awareness of the software and this technical note will allow its ubiquitous use by surgeons. This can help in surgical teaching, appreciation of surgical planning and anatomy. It has the potential to reduce cost and production time compared with outsourcing to outside companies. This software has been already been shown to be used successfully in construction of in-house cutting guides for maxillofacial reconstruction (4). This will also create a next generation of surgeons who are familiar with software technology. Reducing the gap between surgeon and technology will help promote innovation and faster transition of technological advances into the operating room. Introduction: 3D modelling and intra-operative guides are rapidly increasing in use. They have been shown in meta-analyses to increase surgical accuracy, reduce operative time and improve teaching(1, 2). Despite the growing availability of 3D printers, access to 3D models and intra-operative guides is limited by the cost and availability of software and engineers. Methods: This technical note shows how to use 3Dslicer, a free open source multiplatform software available to download from the internet. It can be used to create 3D models from medical imaging such as CT and MRI. Results: 3D objects can be manipulated digitally or printed using 3D printers. They can be used to aid teaching, surgical planning and patient demonstrations. Conclusions: 3Dslicer is an easy to use software which should be in the surgeon's armamentarium. Awareness of the software and this technical note will allow its ubiquitous use by surgeons. This can help in surgical teaching, appreciation of surgical planning and anatomy. It has the potential to reduce cost and production time compared with outsourcing to outside companies. This software has been already been shown to be used successfully in construction of in-house cutting guides for maxillofacial reconstruction (4). This will also create a next generation of surgeons who are familiar with software technology. Reducing the gap between surgeon and technology will help promote innovation and faster transition of technological advances into the operating room.

Repair of Complex Post-Traumatic Facial Dislocations: Indications, Therapeutic Difficulties and Results at Treichville University Hospital, Abidjan, Cote d’Ivoire

Introduction: Complex post-traumatic facial disfigurements are caused by civilian or ballistic trauma. Their repercussions are functional, aesthetic and psychological. The initial emergency or secondary management of facial damage is difficult. The objective is to report, through the clinical observation of three patients, the results of the management of complex facial dislocations in a context of limited technical resources. Patients and methods: Three complex post-traumatic facial dislocations were managed between May 2006 and June 2017. Results: Primary treatment and secondary repair were established on a case-by-case basis. Local autoplasty was the indication of choice. Multidisciplinary management resulted in satisfactory functional and cosmetic outcomes. Two of the patients were lost to follow-up before the end of treatment. Discussion: The complete management of facial dislocations remains difficult and complex, in an extreme exercise situation. In an emergency, the priority is to save the life of the injured person. Several factors are involved in the therapeutic decision: the choice of the maxillofacial reconstruction technique, the availability of the technical platform, the financial capacity and the psychological state of the patient and his entourage. Sequential and multidisciplinary treatment gives satisfactory results in terms of morphology, function and aesthetics, despite the limited technical resources available. Psychological support is an essential complement for successful socio-professional and family reintegration.

Computational Intelligence in Metric Analysis of the Skull in the Context of Maxillofacial Surgery

Anthropometric studies focusing on facial metrics and their proportions form an important research area devoted to observations of the appearance of the human skull. Many different applications include the use of craniometry for maxillofacial reconstruction and surgery. This paper explores the possibility of using selected craniometric points and associated metric to observe spatial changes during the maxillofacial surgery treatment. The experimental dataset includes observations of 27 individuals. The proposed method is associated with the processing of measurements by selected methods of signal processing and computational intelligence. The statistical results point to changes of facial measures before and after the maxillofacial surgery. The proposed method conclusively demonstrates that the area of the mean upper law triangle after surgical treatment is decreased by 8.5%, at the 5% significance level of the two-sample <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">t</i> -test. The classification of selected measurements by a neural network model reached an accuracy of 84.9%.

Mylohyoid Muscle Revisited: Anatomic Features with Clinical Implications in Dentistry

The mylohyoid muscle, one of the suprahyoid group, forms the floor of the mouth. Its main function is swallowing. It is a margin between the sublingual and the submandibular spaces and is important in the pathway of oral and maxillofacial infection. In prosthodontics, it is one of anatomic landmarks that limits the lingual margin of the mandibular denture. Currently, the muscle receives much interest in the fields of maxillofacial reconstruction and rejuvenation. The hemorrhagic issue around the mandibular lingual region is usually involved with the mylohyoid especially in the dental implant installation. This review covers anatomic features of the mylohyoid muscle with diverse clinical implications.

A Narrative Review of u-HA/PLLA, a Bioactive Resorbable Reconstruction Material: Applications in Oral and Maxillofacial Surgery.

The advent of bioresorbable materials to overcome limitations and replace traditional bone-reconstruction titanium-plate systems for bone fixation, thus achieving greater efficiency and safety in medical and dental applications, has ushered in a new era in biomaterial development. Because of its bioactive osteoconductive ability and biocompatibility, the forged composite of uncalcined/unsintered hydroxyapatite and poly L-lactic acid (u-HA/PLLA) has attracted considerable interest from researchers in bone tissue engineering, as well as from clinicians, particularly for applications in maxillofacial reconstructive surgery. Thus, various in vitro studies, in vivo studies, and clinical trials have been conducted to investigate the feasibility and weaknesses of this biomaterial in oral and maxillofacial surgery. Various technical improvements have been proposed to optimize its advantages and limit its disadvantages. This narrative review presents an up-to-date, comprehensive review of u-HA/PLLA, a bioactive osteoconductive and bioresorbable bone-reconstruction and -fixation material, in the context of oral and maxillofacial surgery, notably maxillofacial trauma, orthognathic surgery, and maxillofacial reconstruction. It simultaneously introduces new trends in the development of bioresorbable materials that could used in this field. Various studies have shown the superiority of u-HA/PLLA, a third-generation bioresorbable biomaterial with high mechanical strength, biocompatibility, and bioactive osteoconductivity, compared to other bioresorbable materials. Future developments may focus on controlling its bioactivity and biodegradation rate and enhancing its mechanical strength.

Navigation-assisted maxillofacial reconstruction: accuracy and predictability

The aim of this study was to evaluate the accuracy of navigation-assisted maxillofacial reconstruction and to identify the predictors of the clinical outcomes. A total of 112 patients who underwent navigation-assisted maxillofacial reconstruction with free flaps between 2014 and 2019, performed by a single surgical team, were assessed. Accuracy was evaluated by superimposing the postoperative computed tomography data with the preoperative virtual surgical plan. Predictors of the clinical outcomes affecting the accuracy were identified and analysed. The mean deviation and root mean square (RMS) estimate of the orbital, maxillary, and mandibular reconstructions were 0.88 ± 3.25 mm and 3.38 ± 0.73 mm, 0.77 ± 3.44 mm and 3.69 ± 0.82 mm, and 1.07 ± 4.16 mm and 4.67 ± 3.95 mm, respectively (P < 0.05). There was no significant difference in orbital volume or projection between the preoperative, postoperative, and healthy orbits (P = 0.093 and P = 0.225, respectively). Multivariate linear regression analysis confirmed significant associations between the accuracy of navigation-assisted mandibular reconstruction and preservation of the condyle, type of reconstruction, type of osteosynthesis plate, and number of bony segments. Navigation-assisted midface reconstruction yielded a higher level of accuracy in the final surgical outcome when compared to mandibular reconstruction. Computer-assisted techniques and intraoperative navigation can be an alternative or adjunct to current surgical techniques to improve the final surgical outcome, especially in more complex maxillofacial reconstructions.

Failure of preoperative co-morbidity indices to predict the successful use of the composite scapula free flap for maxillofacial reconstruction in patients with significant medical co-morbidities

The aim of this study was to evaluate the accuracy of validated preoperative patient co-morbidity assessments, including the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP), with the use of the composite scapula free flap (CSFF) in maxillofacial reconstruction in patients with significant medical co-morbidities. A retrospective cohort review was performed at an academic institution, covering the period from July 2010 through January 2019. All patients who underwent reconstruction with a CSFF with significant medical co-morbidities were included. Co-morbidity assessments and risk factors were analyzed by comparing predicted versus observed early and late medical and surgical complications. Forty-five patients met the inclusion criteria. The surgical complication rate was 47%; the medical complication rate was 38%. Over 90% of patients returned to successful function at 3 months post-surgery. The ACS-NSQIP prediction of complications ranged from 58% to 75% for accuracy, 76% to 100% for sensitivity, and 50% to 69% for specificity. The prediction of a serious complication was statistically significant in patients with a Charlson Co-morbidity Index ≥7. Age ≥80 years did not significantly increase the risk of a serious complication (P = 0.23). The ACS-NSQIP failed to predict the successful use of the CSFF for patients with significant co-morbidities undergoing maxillofacial reconstruction. The selection of patients who will tolerate complex reconstruction cannot be based solely on co-morbidity charts and standardized preoperative indices.

C.E. Credit. Advances in Tissue Engineering and Implications for Oral and Maxillofacial Reconstruction

kground: Reconstructive surgery in the oral and maxillofacial region poses many challenges due to the complexity of the facial skeleton and the presence of composite defects involving soft tissue, bone and nerve defects.Methods: Current methods of reconstruction include autologous grafting techniques with local or regional rotational flaps or microvascular free flaps, allografts, xenografts and prosthetic devices.Results: Tissue engineering therapies utilizing stem cells provide promise for enhancing the current reconstructive options.Conclusions: This article is a review on tissue engineering strategies applicable to specialists who treat oral and maxillofacial defects.Practical implications: We review advancements in hard tissue regeneration for dental rehabilitation, soft tissue engineering, nerve regeneration and innovative strategies for reconstruction of major defects.

Innovative High-Pressure Fabrication Processes for Porous Biomaterials-A Review.

Biomaterials and their clinical application have become well known in recent years and progress in their manufacturing processes are essential steps in their technological advancement. Great advances have been made in the field of biomaterials, including ceramics, glasses, polymers, composites, glass-ceramics and metal alloys. Dense and porous ceramics have been widely used for various biomedical applications. Current applications of bioceramics include bone grafts, spinal fusion, bone repairs, bone fillers, maxillofacial reconstruction, etc. One of the common impediments in the bioceramics and metallic porous implants for biomedical applications are their lack of mechanical strength. High-pressure processing can be a viable solution in obtaining porous biomaterials. Many properties such as mechanical properties, non-toxicity, surface modification, degradation rate, biocompatibility, corrosion rate and scaffold design are taken into consideration. The current review focuses on different manufacturing processes used for bioceramics, polymers and metals and their alloys in porous forms. Recent advances in the manufacturing technologies of porous ceramics by freeze isostatic pressure and hydrothermal processing are discussed in detail. Pressure as a parameter can be helpful in obtaining porous forms for biomaterials with increased mechanical strength.

Buccal Fat Pad Graft in Maxillofacial Surgery.

Despite the widespread use of pedicled buccal fat pad (BFP) flap in maxillofacial reconstruction, free nonvascular transfer of this fat is not widely used. Dermal fat transfer to the maxillofacial region is a known procedure with good results; however, it needs a skin incision in the donor site. Resorption of this graft is the other problem. Buccal fat with inherent resistance against resorption and ease of harvest is an interesting option. Six cases are reported in this article for the facial soft tissue augmentation in hemifacial microsomia, scar adhesion, temporal hallowing, and the release of TMJ bony ankylosis and check adhesion.

Non-Suturing Methods of Microvascular Anastomosis in Maxillofacial Reconstruction: A Literature Review

Non-Suturing Methods of Microvascular Anastomosis in Maxillofacial Reconstruction: A Literature Review

Risk Factors of Avulsion Fracture after Iliac Crestal Flap for Jaw Reconstruction

The iliac crestal flap is often used in maxillofacial reconstruction surgery because it has a similar bone contour to jaw bone. However, complications occur frequently in this flap, and the avulsion fracture of the anterior superior iliac spine (ASIS) occurs only in rare cases. The purpose of this study is to evaluate the risk factors affecting fractures that may occur after iliac crestal flap harvesting. In this study, we performed preoperative and postoperative CT scans of the iliac bones of 22 patients who underwent iliac crestal flaps between February 2013 and July 2019. Three of these patients had fractures within 1 month after surgery. After converting DICOM files to a three-dimensional model using Mimics software, some reference points were defined for analysis. The patients were classified into fracture and non-fracture groups. The patients’ age and sex, harvested bone, residual bone and absolute bed rest (ABR) periods were investigated. The patients’ age and sex were not associated with fracture occurrence. There was a statistically significant difference in the width of the anterior–superior part of residual bone. The fracture group showed statistically significantly shorter ABR periods. In the case of the iliac crestal flap, it was found that the factors that can affect the occurrence of fractures are the width of the residual bone and the ABR period. Iliac avulsion fracture can be prevented when the remaining bone is sufficient and the ABR period is prolonged sufficiently.

Consistent Value of Two-Stage Pedicle Flaps in the Age of Microsurgical Maxillofacial Reconstruction

IntroductionUp to the second half of the twentieth century, pedicled flaps marked the gold standard in reconstructive surgery. Followed by the introduction of microsurgical techniques, these flaps were increasingly abandoned. We conducted a retrospective study to determine the value of two-stage pedicle flaps in modern maxillofacial reconstruction.Material & MethodsA chart review from October 2017 to November 2020 was performed to identify patients who were treated by a two-stage pedicle flap in our Department of Oral and Maxillofacial Surgery.ResultsA total of 31 patients, 17 female and 14 males received 36 two-stage pedicle flaps. All patients were in noticeably impaired health condition with a majority of ASA-score 3. The defect location mainly contained extraoral resections (58.3%). A variety of flaps were harvested consisting of buccal flaps, Abbe flaps, forehead flaps, deltopectoral flaps, nasolabial flaps, and a tubed flap.DiscussionThe study outlines two indications for the use of two-stage pedicle flaps. Firstly, as a back-up strategy in heavily pre-treated wound beds and secondly in an almost contrarily indication as a first-choice reconstructive option of the facial skin in esthetic demanding cases.ConclusionThe timesaving and straight forward surgical approach as well as their low postsurgical complications and strong long-time success rates secure the two-stage pedicle flap a justified niche role in times of microsurgical maxillofacial reconstruction.

Improving Patient Education of Facial Fractures Using 3-Dimensional Computed Tomography.

Advances in 3-dimensional modeling have revolutionized presurgical planning for maxillofacial reconstruction, yet little is known about how this technology may affect patient education. This study was designed to evaluate the efficacy of 2-dimensional computed tomography versus 3-dimensional computed tomography for patient education in maxillofacial reconstruction. Crossover study. General otolaryngology outpatients from a tertiary referral center were recruited. A single computed tomography data set of a zygomaticomaxillary complex fracture was used to generate 2 educational video tutorials: one in a 2-dimensional format and one in a 3-dimensional format. The tutorials were embedded into the QualtricsXM platform. Participants were randomly assigned into 2 groups. Group 1 viewed the 2-dimensional tutorial, took a self-assessment survey, took an information recall survey, viewed the 3-dimensional tutorial, and finally took a tutorial comparison survey. Group 2 followed the same sequence but viewed the 3-dimensional tutorial followed by the 2-dimensional tutorial. Group 2 participants (viewing the 3-dimensional tutorial first) scored better on the self-assessment survey than their counterparts in group 1 did (P = .023). Group 2 also scored better on the recall survey (P = .042). Of all participants, 61% preferred the 3-dimensional tutorial, and 31% preferred the use of both tutorials together in the comparison survey. Three-dimensional patient educational tutorial regarding a zygomaticomaxillary complex fracture resulted in better knowledge retention and was preferred over the 2-dimensional format.

Adherence to Computer-Assisted Surgical Planning in 136 Maxillofacial Reconstructions.

ObjectiveTo investigate the adherence to initially planned maxillofacial reconstructions using computer-assisted surgery (CAS) and to identify the influential factors affecting its compliance for maxillofacial reconstruction.Patients and MethodsA retrospective analysis of 136 computer-assisted maxillofacial reconstructive surgeries was conducted from January 2014 to June 2020. The categorical parameters involved age, gender, disease etiology, disease site, defect size, bone flap segments, and flap type. Apart from descriptive data reporting, categorical data were related by applying the Fisher-exact test, and a p-value below 5% was considered statistically significant (P < 0.05).ResultsThe main reasons for partial or non-adherence included unfitness, patient health condition, and other subjective reasons. Out of the total patient population, 118 patients who underwent mandibular reconstruction showed higher CAS compliance (83.9%) compared to the 18 midface reconstruction (72.2%) without any statistically significant difference (p = 0.361). Based on the size of the defect, a significantly higher CAS compliance (p = 0.031) was observed with a minor defect (80.6%) compared to the large-sized ones (74.1%). The bone flaps with two or more segments were significantly (p = 0.003) prone to observe a partial (15.4%) or complete (12.8%) discard of the planned CAS compared to the bone flaps with less than two segments. The malignant tumors showed the lowest CAS compliance when compared to other disorders without any significant difference (p = 0.1).ConclusionThe maxillofacial reconstructive surgical procedures offered optimal compliance to the initially planned CAS. However, large-sized defects and multiple bone flap segments demonstrated a higher risk of partial or complete abandonment of the CAS.

English

BACKGROUND Maxillofacial surgeries vary from simple tooth extraction to maxillofacial reconstruction and rehabilitation. The intricate anatomy of the facial bones and complex vital structures surrounding them makes it challenging for the surgical teams to perform complex surgeries. With the rapid change in technology and modern advancement in virtual surgeries, there is a leap towards improvement in healthcare. To study biomechanical properties, it is imperative to include the principles of physical science in the field of medicine. In recent times, Finite element analysis (FEA) has become a useful tool to study the biomechanical properties of craniofacial structures under different mechanical parameters. Since the human structure's biomechanics is not possible to study on an experimental basis, finite element analysis has become an emerging tool to solve these complex biomechanical equations. The finite element method uses a numerical calculation of small heterogeneous geometry into the simple linear equation and predicts biomechanical responses towards each variation. Although used extensively in engineering, this method finds extensive use in the medical field, from planning surgeries to design external prosthesis. This method's most significant advantage includes studying a model outside the body, designing an idle surgical instrument and hardware, models that can be replicated based on user requirements, no ethical consideration needed, and print prosthesis that exactly resembles a typical anatomical structure. This method has certain limitations: high cost, technical flaws, and inability to replicate exact clinical conditions. This review article covers the current FEA scope in maxillofacial surgeries, steps in planning surgeries, advantages, disadvantages and the modifications needed to refine it for future research. KEYWORDS Finite Element Analysis, Craniomaxillofacial Trauma, Orthognathic Surgery, FEA

Inferiorly Based Nasolabial Flap: A Reliable Option for Oral and Maxillofacial Reconstruction.

Abstract Introduction: Reconstruction of defects in the maxillofacial region can be challenging. Anatomy, location and size of the defect are major determinants of type of flap that could be used whether local, regional or distant. Nasolabial flap is one of the local flaps that can be used for reconstructing small to moderate size soft tissue defects, especially when microsurgical free flaps are less feasible due to lack of infrastructure, expertise or financial constraints. Aims and Objectives: To study the effectiveness of the nasolabial flaps in reconstruction of orofacial defects of various origins. Materials and Methods: A prospective study was conducted on 37 patients (49 nasolabial flaps) 25 unilateral flaps & 12 bilateral flaps. Of these, 30 patients had reconstruction following oncological resection. All flaps were inferiorly based, and 36 flaps required a second stage for separation after 3 weeks. Patients were evaluated for postoperative complications, flap uptake, donor site morbidity, postoperative extraoral scarring and patient’s satisfaction. Results: Good results in form of function and cosmesis were obtained in most of patients. Postoperative complications were relatively minor as tip of flap necrosis, and oro-cutaneous fistula. The average time taken for flap harvesting was 43 minutes for bilateral nasolabial flaps and 27 minutes for unilateral ones. Conclusion: The nasolabial flap is a simple and reliable flap that can be used in reconstruction of small to moderate sized defects in orofacial region with good cosmetics and functional outcomes.