Virtual Surgical Planning in Precise Maxillary Reconstruction With Vascularized Fibular Graft After Tumor Ablation

Virtual Surgical Guidance Improves Quality of Life Following Scapular Free-Flap Reconstruction of Maxillary Defects

BACKGROUND

The best approach to maxillary reconstruction with negative impact on the patient's quality of life (QOL) remains the subject of debate.

PURPOSE

This study was designed to evaluate the QOL outcomes following maxillary reconstruction using a scapular-free flap, with and without the computer-aided design and computer-aided manufacturing (CAD/CAM) technique.

STUDY DESIGN, SETTING, SAMPLE

A prospective randomized controlled clinical trial was performed following the CONSORT checklist. To be included, patients suffering from maxillary defects without previous surgery or lymph node involvement were selected. Patients with poor oncological prognosis, deficient performance status, preoperative chemotherapy, or radiotherapy, besides vascular contraindications, were excluded.

PREDICTOR VARIABLE

The predictor variable was the reconstruction technique, grouped into two equal categories. Patients were randomly assigned to reconstruction with a scapular-free flap, with the control group not utilizing a guide and the study group utilizing a CAD/CAM-customized guide.

MAIN OUTCOME VARIABLE

The primary outcome variable was the various domains of QOL, measured using the University of Washington Quality of Life score, 12 months after reconstruction.

COVARIATES

Age; sex; scapular flap side; and maxillary defect tumour type, histopathology, side, length, class, sagittal, and axial differential areas were considered.

ANALYSES

Shapiro-Wilk and Kolmogorov-Smirnov tests were performed for normality. For comparisons between the two groups, Student's t-test and Mann-Whitney test were used. The category variables were compared using the χ2 test. P ≤ .05 was considered statistically significant.

RESULTS

The sample was composed of twenty-two eligible patients, eleven in each group. The mean age of the control group was (50.09 ± 17.14) years, and 45.45% were male, while in the study group, the mean age was (48.36 ± 14.14) years, with 36.36% male. All the patients were evaluated, showing statistically significant differences between control and study groups in terms of pain, appearance, chewing, swallowing, speech, and shoulder (P ≤ .05), indicating that the scapular-free flap with a CAD/CAM osteotomy guide had improved the patient's QOL.

CONCLUSION AND RELEVANCE

The findings of this study indicate that virtual surgical planning with a CAD/CAM customized osteotomy guide using a scapular-free flap can improve QOL in maxillary reconstruction in terms of pain, appearance, chewing and swallowing food, pronouncing words, and shoulder QOL outcomes.

Development and validation of a novel craniofacial statistical shape model for the virtual reconstruction of bilateral maxillary defects

Bilateral maxillary defects are a challenge for fibula free flap reconstruction (FFFR) surgery due to limitations in virtual surgical planning (VSP) workflows. While meshes of unilateral defects can be mirrored to virtually reconstruct missing anatomy, Brown class c and d defects lack a contralateral reference and associated anatomical landmarks. This often results in poor placement of osteotomized fibula segments. This study was performed to improve the VSP workflow for FFFR using statistical shape modeling (SSM) - a form of unsupervised machine learning - to virtually reconstruct premorbid anatomy in an automated, reproducible, and patient-specific manner. A training set of 112 computed tomography scans was sourced from an imaging database by stratified random sampling. The craniofacial skeletons were segmented, aligned, and processed via principal component analysis. Reconstruction performance was validated on a set of 45 unseen skulls containing various digitally generated defects (Brown class IIa-d). Validation metrics demonstrated promising accuracy: mean 95th percentile Hausdorff distance of 5.47 ± 2.39 mm, mean volumetric Dice coefficient of 48.8 ± 14.5%, compactness of 7.28 × 105 mm2, specificity of 1.18 mm, and generality of 8.12 × 10-6 mm. SSM-guided VSP will allow surgeons to create patient-centric treatment plans, increasing FFFR accuracy, reducing complications, and improving postoperative outcomes.

Risk Factors for Hardware Removal Following Bimaxillary Surgery: A National Database Analysis

Orthognathic surgery typically relies on the rigid fixation of fracture fragments using metal hardware. Though hardware is usually intended to be implanted permanently, the removal of hardware (ROH) is sometimes indicated for a variety of reasons. The authors sought to identify risk factors for ROH following orthognathic surgery. The authors conducted a retrospective analysis of the Merative MarketScan Research Databases, 2007-2021 using Current Procedural Terminology (CPT) and International Classification of Disease (ICD-9 and ICD-10) codes to identify patients who underwent an index Le Fort 1 osteotomy and bilateral sagittal split osteotomy operation on the same day. Statistical analysis involved χ2, Shapiro-Wilk, Wilcoxon-Mann-Whitney, Poisson regression, and multivariable logistic regression tests. 4698 patients met the inclusion criteria. The mean age at surgery was 25 years, and 57% were female. ROH occurred in 5.9% of patients. The mean time to hardware removal was 190.5±172.4 days. In a multivariate logistic regression, increased odds of ROH were associated with older patient age [OR: 1.02 (1.01-1.03), P=0.046], sleep apnea [OR: 1.62 (1.13-2.32), P=0.018], and craniofacial syndrome and/or cleft diagnoses [OR: 1.88 (1.14-2.55), P<0.001]. In the same model, postoperative oral antibiotic prophylaxis was not associated with ROH (P=0.494). The incidence of all-cause complications [IRR: 1.03 (1.01-1.05), P<0.001] rose over the study period, while the incidence of ROH did not change significantly (P=0.281). Patients at elevated risk should be counseled on the increased possibility of a second operation for ROH before having orthognathic surgery to ensure expectations and health care utilization decisions align with the evidence.

Stacked fibula flap for unilateral total maxillectomy reconstruction with orbital preservation

Unilateral total maxillectomy is indicated for locally advanced maxillary tumors that require complete removal of the midface bony structure and inferior orbital rim. Reconstruction of this defect is challenging due to aesthetic and functional concerns. A retrospective review of patients at two tertiary-care institutions undergoing unilateral total maxillectomy reconstruction with a stacked fibula flap from 2018 to 2022 was performed. Each patient's clinical course was reviewed, and attention was focused on the demonstration of surgical steps with photos. Twenty patients underwent stacked fibula flap reconstruction for unilateral total maxillectomy orbital preservation defects. Surgical extirpation was performed for malignancy (80%, 16/20) and for osteoradionecrosis or benign tumor in 20% (4/20). The complication rate was 30% (6/20). Most flaps survived (95%, 19/20). We present a modified, reproducible method of fibula flap reconstruction for unilateral total maxillectomy with orbital preservation that only requires two segments and maintains positive aesthetic and functional results.

Evolution of Medical Modeling and 3D Printing in Microvascular Midface Reconstruction: Literature Review and Experience at MD Anderson Cancer Center

Reconstruction of the midface represents a challenge for reconstructive microsurgeons given the formidable task of restoring both aesthetics and functionality. In particular, preservation of proper globe positioning and maintaining normal vision are as important as restoring the proper projection of the midface and enabling a patient to speak and eat as normally as possible. The introduction of virtual surgical planning (VSP) and medical modeling has revolutionized bony reconstruction of the craniofacial skeleton; however, the overwhelming majority of studies have focused on mandibular reconstruction. Here, we introduce some novel advances in utilizing VSP for bony reconstruction of the midface. The present review aims (1) to provide a review of the literature on the use of VSP in midface reconstruction and (2) to provide some insights from the authors' early experience.

Virtual Surgical Planning and 3D-Printed Surgical Guides in Facial Allotransplantation

The complex three-dimensional (3D) anatomy in facial allotransplantation creates a unique challenge for surgical reconstruction. Evolution of virtual surgical planning (VSP) through computer-aided design and computer-aided manufacturing has advanced reconstructive outcomes for many craniomaxillofacial indications. Surgeons use VSP, 3D models, and surgical guides to analyze and to trial surgical approaches even prior to entering the operating room. This workflow allows the surgeon to plan osteotomies and to anticipate challenges, which improves surgical precision and accuracy, optimizes outcomes, and should reduce operating room time. We present the development, evolution, and utilization of VSP and 3D-printed guides in facial allotransplantation at our institution, from guide conception to first clinical case.

Aesthetic reconstruction of onco-surgical maxillary defects using free scapular flap with and without CAD/CAM customized osteotomy guide

BACKGROUND

Reconstruction of the maxillary defects following tumor ablation remains to be a challenge for surgeons. Virtual surgical planning (VSP), intraoperative cutting guides and stereolithographic models provides the head and neck reconstructive surgeon with powerful tools for complex reconstruction planning. Despite its use in fibular osteocutaneous reconstruction, application to the scapular free flap has not been as widely reported. The aim of this study was to compare aesthetic results and operation time of free scapular flap, with and without computer-aided design and computer-aided manufacturing (CAD/CAM) customized osteotomy guide, for reconstruction of maxillary defects.

METHODS

In this prospective randomized controlled clinical trial study, we randomly assigned 22 patients with maxillary defects who were scheduled to undergo maxillary reconstruction with either free scapular flap with CAD/CAM customized osteotomy guide; study group (n = 11) or free scapular flap without CAD/CAM customized osteotomy guide; control group (n = 11). All patients were followed up for 3 months. The aesthetic outcome, operation and ischemic times were evaluated and compared.

RESULTS

Aesthetic outcomes were evaluated objectively by means of differential surface area (sagittal and axial) measurement, which showed improved aesthetic outcome (contour symmetry) in the study group with a mean of (241.39 ± 113.74 mm²), compared to patients in control group with a mean of (358.70 ± 143.99 mm²). There were significant differences between the two groups (P < 0.05). Aesthetic outcomes were also evaluated subjectively by means of visual analogue scale (VAS) and patient's satisfaction score (PSS). The postoperative aesthetic appearance was better in the study group with more patients satisfied than that in control group and there were statistically significant differences (P = 0.039). The mean total operative time was 678.81 min and 777.18 min in the study group and control group respectively (P < 0.05) and the mean ischemia time was 133.18 min and 195.72 min for study group and control group respectively (P < 0.05). The ischemia time and total operative time were shorter in the study group compared to those in the control group and there were no flap losses in both groups.

CONCLUSION

The use of CAD/CAM prefabricated cutting guides facilitates scapular flap molding and placement, minimizes ischemic time and operating time as well as improves aesthetic outcomes. Trial registration This trial was registered at ClinicalTrials.gov.

REGISTRATION NUMBER

NCT03757286. Registration date: 28/11/2018.

Guided Biopsy of a Radiopaque Lesion Simultaneous with Dental Implants’ Placement: A Multidisciplinary Approach

Background: New technologies and techniques allow us to offer better solutions for patients’ needs. Specifically, guided surgery is usually flapless, and the resulting prosthetic rehabilitation often includes immediate loading. Thus, bleeding risk is controlled, and more comfortable prosthetic procedures are performed. Guided surgery decreases surgical risks and is less invasive. The aim of this article is to present a case of guided osteotomy for bone biopsy and implant placement. Methods: CBCT was performed for the patient’s bone examination, an optical scanner was used for intra-oral images, and surgical certified software was applied for the osteotomy planning and the surgeon’s guide realization. Case report: The patient’s question is about left maxilla prosthetic rehabilitation. During the oral cavity and X-ray examination, a radiopacity with a feathered edge was found; in order to detect the finding, a CBCT was performed, and the surgery was planned. A bone biopsy was performed simultaneously with the implant’s placement through a drill guide. The specimen sent for histological exam showed osteosclerosis. Conclusions: It is the opinion of the authors that by involving and combining close collaboration and communication, several professional specializations (clinicians and radiologists) can improve the treatments for better patient care.

The state of virtual surgical planning in maxillary Reconstruction: A systematic review

Virtual surgical planning (VSP) and computer aided design utilization in head and neck reconstruction has become increasingly popular within the discipline. Advocates of the technology over traditional free hand surgery cite benefits including improved intraoperative efficiencies and postoperative outcomes that have been demonstrated during mandibular reconstruction. More recently, VSP for maxillary and mid facial reconstruction, generally considered more complex than their mandibular counterparts, have been applied with the hopes of similar benefits. However, our literature search revealed no large-scale randomized control trial substantiating these benefits. As such, the aim of this review was to synthesize the existing research on utilization of VSP in the context of maxillary reconstruction. Three databases were systematically searched for articles pertaining to maxillary reconstruction for oncologic, traumatic, or osteoradionecrosis indications. Four hundred and fourteen unique articles were reviewed by two independent reviewers ultimately revealing sixteen studies appropriate for qualitative synthesis including 142 patients. Results of our studies reveal the extreme heterogenicity of application of this technology under the label of virtual surgical planning. Outcome reporting methods were grossly inconsistent amongst all the articles resulting in inability to appropriately synthesize data quantitatively for a meta-analysis. Overall, there was no standard of reporting outcomes of maxillary reconstruction, and no randomized trials comparing virtual surgical planning versus freehand surgery and therefore there is insufficient data to objectively prove purported benefits. To facilitate future comparative studies, a minimal standard of reporting for maxillary VSP is presented and the need for a randomized control trial is highlighted.

The role of computer aided design/computer assisted manufacturing (CAD/CAM) and 3- dimensional printing in head and neck oncologic surgery: A review and future directions

Microvascular free flap reconstruction has remained the standard of care in reconstruction of large tissue defects following ablative head and neck oncologic surgery, especially for bony structures. Computer aided design/computer assisted manufacturing (CAD/CAM) and 3-dimensionally (3D) printed models and devices offer novel solutions for reconstruction of bony defects. Conventional free hand techniques have been enhanced using 3D printed anatomic models for reference and pre-bending of titanium reconstructive plates, which has dramatically improved intraoperative and microvascular ischemia times. Improvements led to current state of the art uses which include full virtual planning (VP), 3D printed osteotomy guides, and patient specific reconstructive plates, with advanced options incorporating dental rehabilitation and titanium bone replacements into the primary surgical plan through use of these tools. Limitations such as high costs and delays in device manufacturing may be mitigated with in house software and workflows. Future innovations still in development include printing custom prosthetics, 'bioprinting' of tissue engineered scaffolds, integration of therapeutic implants, and other possibilities as this technology continues to rapidly advance. This review summarizes the literature and serves as a summary guide to the historic, current, advanced, and future possibilities of 3D printing within head and neck oncologic surgery and bony reconstruction. This review serves as a summary guide to the historic, current, advanced, and future roles of CAD/CAM and 3D printing within the field of head and neck oncologic surgery and bony reconstruction.

Impact of intraoperative ischemia time on acute complications of head and neck microvascular free tissue transfer: A systematic review and meta-analysis

BACKGROUND

To evaluate the relationship between intraoperative ischemia time with acute microvascular free tissue transfer (MFTT) complications in head and neck reconstruction.

METHODS

A systematic review using PRISMA guidelines was performed. Inclusion encompassed all available studies published and indexed using PubMed, Medline, and Embase. Meta-analyses were performed using the Cochrane Review Manager tool. Methodological Index for Non-Randomized Studies (MINORS), the Revised Cochrane risk-of-bias tool for randomized trials, and the NIH Study Quality Assessment Tool for non-randomized prospective studies.

RESULTS

A total of 430 citations were reviewed. 25 were included in our overall qualitative analysis, and 14 for meta-analysis. When comparing ischemia times for flaps with and without complications, no significant difference was observed (p = 0.98). Additionally, in a separate cohort, no significant effect was realized when correlating ischemia time to overall rates and total complications.

CONCLUSION

Ischemia time was not significantly different between those with and without acute flap complications.

Modified Reconstruction of Brown II Defects With Anterolateral Thigh Flaps Following Tumor Resection

OBJECTIVE

Maxillary defects reconstructed with flaps usually cause nasalomaxillary fistula, discomfort oral lining, and poor function of denture. To resolve these problems, this study introduces a modified method of anterolateral thigh flap (ALTF) with skin and myofascial paddles to reconstruct nasal and oral lining of maxillary defects.

METHODS

This study retrospectively reviewed 66 consecutive patients of Brown II maxillary defects following tumor resection reconstructed with ALTFs of modified or conventional methods. In modified group, oral lining was reconstructed with myofascial paddle and nasal lining was reconstructed with skin paddle. The functional and aesthetic outcomes, and the scores based on the University of Washington quality of life questionnaire were assessed.

RESULTS

All flaps were successful in reconstruction of Brown II maxillary defects. No nasalomaxillary fistula and obstruction of the nasal cavity were found in modified ALTFs group. The functions of removable denture were better in modified ALTFs group. There was no significant difference about tumor recurrence, range of mouth opening, and aesthetic outcomes between the 2 groups.

CONCLUSIONS

The modified method of ALTF with skin and myofascial piddle to reconstruct Brown IIa and IIb defects following tumor resection is simple and reliable, which improves the oral comfortability and function of denture, and avoids obstruction of the nasal cavity.

Computer-Aided Design and Manufacturing versus Conventional Surgical Planning for Head and Neck Reconstruction: A Systematic Review and Meta-Analysis

BACKGROUND

Virtual surgical planning and computer-aided design/computer-aided manufacturing (CAD/CAM) for complex head and neck reconstruction has a number of cited advantages over conventional surgical planning, such as increased operative efficiency, fewer complications, improved osseous flap union, immediate osseointegrated dental implant placement, and superior functional and aesthetic outcomes. The authors performed a systematic review and meta-analysis of the available evidence on CAD/CAM maxillofacial reconstruction with the primary purpose of determining which approach is more efficacious.

METHODS

In accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a PubMed and Embase database search was performed to identify English-language, human-subject studies of CAD/CAM-assisted head and neck reconstruction. All comparative studies were included in a meta-analysis to identify differences in operative time, ischemia time, surgical-site occurrence, microvascular complication, and partial or total flap loss between the two groups. All included studies (comparative and noncomparative) were used in the systematic review, summarizing the various flap characteristics, technical nuances, and functional and aesthetic outcomes.

RESULTS

Twelve articles were included in the meta-analysis, representing 277 patients in the CAD/CAM group and 419 patients in the conventional group. CAD/CAM was associated with 65.3 fewer minutes of operating room time (95 percent CI, -72.7 to -57.9 minutes; p < 0.0001) and 34.8 fewer minutes of ischemia time (95 percent CI, -38 to -31.5 minutes; p < 0.0001). There were no significant differences in surgical-site occurrence, nonunion, flap loss, microvascular complications, or hardware-related complications.

CONCLUSIONS

CAD/CAM is associated with shorter operating room and ischemia times. There are no significant differences in flap or hardware-related complications between CAD/CAM and conventional surgical planning.

Accuracy of Computer-Assisted Surgery in Maxillary Reconstruction: A Systematic Review

Computer-assisted surgery (CAS) in maxillary reconstruction has proven its value regarding more predictable postoperative results. However, the accuracy evaluation methods differ between studies, and no meta-analysis has been performed yet. A systematic review was performed in the PubMed, Embase, and Cochrane Library databases, using a Patient, Intervention, Comparison and Outcome (PICO) method: (P) patients in need of maxillary reconstruction using free osteocutaneous tissue transfer, (I) reconstructed according to a virtual plan in CAS software, (C) compared to the actual postoperative result, and (O) postoperatively measured by a quantitative accuracy assessment) search strategy, and was reported according to the PRISMA statement. We reviewed all of the studies that quantitatively assessed the accuracy of maxillary reconstructions using CAS. Twelve studies matched the inclusion criteria, reporting 67 maxillary reconstructions. All of the included studies compared postoperative 3D models to preoperative 3D models (revised to the virtual plan). The postoperative accuracy measurements mainly focused on the position of the fibular bony segments. Only approximate comparisons of postoperative accuracy between studies were feasible because of small differences in the postoperative measurement methods; the accuracy of the bony segment positioning ranged between 0.44 mm and 7.8 mm, and between 2.90° and 6.96°. A postoperative evaluation guideline to create uniformity in evaluation methods needs to be considered so as to allow for valid comparisons of postoperative results and to facilitate meta-analyses in the future. With the proper validation of the postoperative results, future research might explore more definitive evidence regarding the management and superiority of CAS in maxillary and midface reconstruction.

Advances in Oromandibular Reconstruction with Three-Dimensional Printing

The mandibular structures are a complex anatomical structure that is fundamental to many physiological and homeostatic functions. It may be involved in many pathological processes that require partial or complete removal. When this happens, reconstruction is mandatory to improve cosmetic outcome with its effect on social interaction as well as to provide an opportunity for complete dental rehabilitation with restoration of all physiological functions. This article will review the different reconstructive options available for complex defects of the mandibular complex. It will highlight the surgical options available to maximize functional restoration. Finally, it will discuss computer modeling to optimize reconstructive planning.

Microvascular reconstruction in head and neck cancer - basis for the development of an enhanced recovery protocol

Introduction

Microvascular reconstructions after head and neck cancer are among the most complicated procedures in plastic surgery. Postoperative complications are common, which often leads to prolonged hospital stay. Enhanced recovery after surgery (ERAS) is a peri- and postoperative care concept with the aim of achieving pain- and risk-free surgery. It has been previously established as superior to conventional care for a wide variety of procedures, including microsurgical procedures such as reconstructions of the breast. Several ERAS protocols for microvascular head and neck cancer reconstructions have been proposed, although most of these are based on extrapolated evidence from different surgical specialties. Results from the implementation of ERAS for these procedures are inconsistent.

Methods

The current study investigates our clinical experience of head and neck cancer reconstruction for the period of 2014-2016 with the aim of establishing a list of functional discharge criteria. By combining these with the current published knowledge on the subject, we developed an ERAS protocol.

Results

We performed 89 microvascular procedures in the study period, of which 58 were in the oral cavity/sinuses and 31 were laryngopharyngeal. Most cases were squamous cell carcinoma (89%). The average LOS was 20.3 days in both groups. Postoperative complications included infection (37%), 30-days re-operations (19%), and re-admissions (17%). Furthermore, we identified the following discharge criteria: adequate pain relief, ambulation, sufficient nutritional intake, normal infection-related blood parameter results and absence of fever, bowel function, and closure of tracheostomy.

Conclusion

Based on our retrospective analysis and identified discharge criteria, we present an approach to develop an ERAS protocol for microvascular reconstruction after head and neck cancer.

Orthodontics First in Hemimandibular Hyperplasia. "Mind the Gap"

A 32-year-old man was referred to the Division of Orthodontics of the University of Naples "Federico II", with a 15-year history of gradually increasing right-sided facial asymmetry. Clinical and radiological examinations was consistent to hemimandibular hyperplasia, a rare developmental asymmetry characterized by three-dimensional enlargement of one-half of the mandible. The standard surgical-orthodontic management was proposed to the patient. However, he refused to undergo bimaxillary orthognatic surgery. Therefore, a different treatment was proposed based on the orthodontic technique of pre-surgical decompensation and post-surgical refinement used in bimaxillary orthognatic surgery planning, and surgical intervention with a condylectomy. The dental arches were evenly levelled out with a multi-bracket treatment and then the condylectomy was performed. Orthodontic treatment continued with a levelling and torque control by 0.19 × 0.25 SS arch and physiotherapy. At the three-month follow-up, the patient showed anterior and posterior bite rebalancing, arch intercuspation recovery, and anterior open bite closure due to muscular self-rebalancing. The two-year follow-up showed regular mandibular dynamic, orthodontic appliances were removed, and the patient was instructed to wear retainer for the following months. The final result was aesthetically reasonable for the patient, although slight asymmetry of the chin persisted.

Intraoral Approach for Surgical Treatment of Psammomatoid Juvenile Ossifying Fibroma

Psammomatoid juvenile ossifying fibroma (PJOF) is a rare benign tumor that usually affects the paranasal sinuses, orbit, and skull. In most cases, extensive incisions are necessary for full access to the tumor site. The aim of this paper is to report a case of extensive PJOF in which an intraoral surgical approach was performed with complete excision of the tumor. A female patient, 18-year old had a deforming volume increase in the region of the left facial middle third with an approximate evolution time of 2 years. She complained of headache, epiphora in the left eye, and total obstruction of the left nostril. Extraoral examination showed facial asymmetry with dystopia, ocular proptosis, and considerable sclera exposition of the left eye. Tomography examination showed a mixed aspect lesion on the left side of the face, well delimited. The intraoral surgical approach was chosen for the excision of the lesion. Under general anesthesia and nasotracheal intubation, total resection was performed, followed by exodontia of the directly involved teeth. In the definitive histopathological examination, the diagnosis was confirmed. The patient is currently with 2 years and 6 months of postoperative follow-up and has good healing of intraoral surgical wounds and stable occlusion. Extraoral examination showed harmonic projection of the facial middle third, but still with excessive exposure of the sclera of the left eye due to the defect in the orbital floor. The surgical treatment of PJOF was possible by intraoral approach, even taking into account the limitations of the access and the complexity of the anatomy of the facial bones involved.

Primary Maxillary Reconstruction With Fibula Flap and Dental Implants: A Comparative Study Between Virtual Surgical Planning and Standard Surgery in Class IIC Defects

PURPOSE

Oncological patients who undergo bilateral subtotal maxillectomies develop functional and esthetic sequelae that require immediate reconstruction. The purpose of this study is to evaluate the primary reconstruction of maxillary defects with fibula flap and dental implants assisted by virtual surgical planning (VSP) and to assess the postoperative outcomes compared with standard surgery.

MATERIAL AND METHODS

A retrospective study was designed between January 2016 and April 2020 with 12 oncologic patients who underwent subtotal bilateral maxillectomy. Six consecutive patients were treated by standard surgical procedure (SS) at the beginning of the study. In 2018, the VSP was implemented, and 6 consecutive patients were treated using this technique. All patients were rehabilitated with Ticare implants and implant prostheses. Anatomic position of the bone, bone apposition, change of vertical distance, and horizontal shift, the operative and ischemia time, the esthetic results, and the functional rehabilitation were evaluated and compared.

RESULTS

The position of the bone in anatomical position was 100% in the VSP group vs 66% in the SS group. The bone apposition was 100% in the VSP group vs 83.3%. The change of vertical distance and the horizontal shift were lower in the VSP group (P < .05). The ischemia time and operative time were shorter in the VSP group (P < .05). A good esthetic result was achieved in 83.3% in the VSP group vs 33.3% in the SS group; 81 dental implants and 1 zygomatic implant were placed. The success rate was 95% in the VSP group and 92.6% in the SS group. All patients were rehabilitated with implant prosthesis.

CONCLUSIONS

VSP improves the accuracy of midface reconstruction (class IIC defect) with a better anatomical position of the bone, a higher rate of bone contact, and a lower change in vertical distance compared with standard surgery. It significantly improves the esthetic result, reduces ischemia time, and operation time.

Combination of biomechanical evaluation and accurate placement of dental implants: a new concept of virtual surgery in maxillary and mandibular functional reconstruction

Biomechanics are crucial for bony regeneration and survival of implants in functional maxillary and mandibular reconstructions. However, we know of no study that has included an analysis of biomechanics to guide the optimal position of a fibular graft in virtual surgery. This study was designed to evaluate the combination of biomechanics and accurate placement of implants for virtual surgery in reconstruction of the jaw using fibular grafts. Thirty-one patients had maxillary or mandibular reconstruction with vascularised fibular grafts and the immediate placement of dental implants. Virtual studies were made preoperatively to evaluate the biomechanics and to assess the position of the fibular grafts with minimal distribution of stress. All operations proceeded accurately and with no complications with a mean (range) of 14 (6-20) months' follow-up. According to the individual biomechanical evaluations, the optimal position for the fibular graft is probably the middle of the mandibular body or below the bottom of the maxillary sinus. The combination of biomechanical evaluation and accurate placement of dental implants is a new concept that could achieve good biomechanical positioning of fibular grafts in the jaw and a desirable level of accuracy for functional reconstruction.

Virtual surgical planning in fibula free flap head and neck reconstruction: A systematic review and meta-analysis

BACKGROUND

The traditional approach to head and neck reconstruction is considered challenging, requiring a subjective assessment of an often-complex defect followed by careful modelling of a bony flap to match this. The introduction of Virtual Surgical Planning (VSP) has provided the surgeon with a means to increase efficiency, precision and overall patient outcomes. This study aims to compare VSP and traditional head and neck reconstructions utilising fibula free flaps with regards surgical efficiency and patient outcomes.

METHODS

A systematic search of the PubMed and Medline databases was performed from the date of their inception through to August 2018 to evaluate and compare VSP and non-VSP cohorts in the context of fibula free flap head and neck reconstruction. Primary comparative outcomes included operative and ischaemic time, with secondary outcomes including complications rates, measures of accuracy and financial benefits.

RESULTS

One hundred and fifty-three articles were identified. Twenty-three articles were included in the review, comprising a total of 713 patients. VSP was associated with significantly decreased intraoperative time (Standardised Mean Difference -1.01; 95% CI -1.23 to 0.80; p = 0.000) and ischaemic time (Standardised Mean Difference -1.55; 95% CI -1.87 to -1.23, p = 0.002). VSP was also associated with reduced orthognathic deviation from an ideal outcome when compared to conventional techniques. No statistically significant differences in complication rates between conventional and VSP techniques were identified.

CONCLUSION

The results of this meta-analysis suggests that VSP confers significant benefits with respect to improved orthognathic accuracy, ischaemic times and intraoperative times without any significant increase in complications. Recommendations for ongoing research are suggested.

Virtual Surgical Planning and Hardware Fabrication Prior to Open Reduction and Internal Fixation of Atrophic Edentulous Mandible Fractures

Mandibular fractures are a common injury encountered by facial trauma surgeons. A majority of these cases are in dentate patients and can predictably be treated with several different open or closed techniques. Edentulous mandible fractures can be challenging as maxillomandibular fixation, either as the sole treatment or used for fracture reduction and stabilization prior to internal fixation, is not possible. The atrophic edentulous mandible fracture poses an even greater challenge, as there is more sclerotic bone present and less bone volume for bony contact, both of which can impair healing. In addition, with less bone mass, available plate adaptation and fixation are difficult. In recent years, virtual surgical planning (VSP) has been increasingly used in craniofacial and maxillofacial surgeries as well as in dentistry. Utilizing VSP to fabricate the necessary hardware prior to open reduction and internal fixation of atrophic edentulous mandible fractures can be helpful in treating these cases. Two cases where this method was used are presented.

Evaluation of accuracy and sensory outcomes of mandibular reconstruction using computer-assisted surgical simulation

PURPOSE

To introduce a modified protocol for mandibular reconstruction and evaluate the protocol using a standardized assessment method.

METHOD

This retrospective study involved a case series of nine patients who underwent mandibular reconstruction between 2015 and 2017. The modular protocol comprised three novel modifications in terms of computer-assisted surgical simulation (CASS); surgical template (ST), and surgical procedure. The standardized postoperative evaluation consisted of operation time, part comparison analysis (PCA), facial symmetry, and mechanical quantitative sensory testing.

RESULTS

The surgery successfully removed the affected mandible and preserved the inferior alveolar neurovascular bundle (IANB). PCA revealed that the mean error and standard deviation were 0.92 and 0.96 mm, respectively, for all mandibular surface sites. Follow-up results showed good facial symmetry, existence of sensation in lower lip, and no significant differences in pulp vitality between both sides (p = 0.181). Also, the results showed a reduction in the overall operating time.

CONCLUSION

The modified mandibular reconstruction method used in this study could repair lateral mandibular defects and preserve the sensory function of the chin and lower lip.

The Biaxial Double-Barrel Fibula Flap-A Simplified Technique for Fibula Maxillary Reconstruction

PURPOSE

Previously described techniques for microvascular fibula reconstruction of Brown Class II to IV maxillectomy defects are complex, require multiple osteotomies, result in a short pedicle, and inadequately reconstruct the dental alveolus in preparation for endosseous implants. This report describes a simplified technique for Brown Class II to IV defects that re-creates facial support, allows for dental reconstruction with appropriately positioned implants, and maintains adequate pedicle length.

MATERIALS AND METHODS

A retrospective chart review was performed of all patients with Brown Class II to IV maxillectomy defects immediately reconstructed with a biaxial double-barrel fibula flap technique. The reconstructive surgeon evaluated each patient at least 1 month after reconstruction for enophthalmos, facial symmetry, nasal patency, satisfactory jaw position, deglutition, intelligible speech, and intraoperative need for vein grafting.

RESULTS

The sample was composed of 6 patients (mean age, 54 yr; range, 33 to 78 yr; 67% women) who underwent reconstruction with the biaxial double-barrel fibula flap technique for Brown Class II to IV defects. None of these patients required vein grafting. None of these patients had flap failure. Diagnoses for these patients were a hybrid odontogenic tumor (n = 1), squamous cell carcinoma (n = 3), adenoid cystic carcinoma (n = 1), and sinonasal melanoma (n = 1). All 6 patients had excellent facial contour and malar projection, regular oral intake, 100% intelligible speech, and a new maxillary skeletal Class I relation without need for intraoperative vein grafting. One patient developed enophthalmos related to inferior rectus sacrifice and removal of orbital fat. Complications included development of nasal synechia and occlusion of the maxillary sinus ostium (n = 1).

CONCLUSIONS

The biaxial double-barrel fibula flap technique achieves the goals of providing adequate facial support and an alveolar segment amenable to implant dentistry. It allows for intelligible speech, deglutition, orbital support, and separation of the oronasal, orbital, and sinus cavities. In addition, it minimizes the need for vein grafting.

Maxillary reconstruction using rectus femoris muscle flap and sagittal mandibular ramus/coronoid process graft pedicled with temporalis muscle

BACKGROUND

Maxillary reconstruction using various pedicled and free-tissue transfer techniques with bone graft or without bone graft has some drawbacks. In this study, we demonstrate maxillary reconstruction using femoris rectus muscle flap and sagittal mandibular ramus/coronoid process graft pedicled with temporalis muscle through the modified lateral lip-submandibular approach.

MATERIAL AND METHODS

Nine patients suffering from maxillary defects secondary to maxillary cancer ablation, who underwent maxillary reconstruction using rectus femoris muscle flap and sagittal mandibular ramus/coronoid process graft pedicled with temporalis muscle, were enrolled into this study between November 2015 and August 2017.

RESULTS

All patients who underwent the maxillary reconstruction using femoris rectus muscle flap and sagittal mandibular ramus/coronoid process graft pedicled with temporalis muscle presented satisfactory postoperative function, with adequate mouth opening, optimal esthetic outcome and no restrictions on the diet. Every rectus femoris muscle flaps mucosalized well within five weeks. No donor site functional impairment or complications were observed.

CONCLUSIONS

The technique is a feasible and acceptable technique for the maxillary reconstructions. It is safe, quick and simple to harvest. It also presents an optimal esthetic and satisfactory functional outcome with the advantage of low morbidity of the donor site. Combined with the three-dimension reconstruction, this technique can improve the postoperative outcomes.

Obturators versus flaps after maxillary oncological ablation: A systematic review and best evidence synthesis

Maxillary defects can be resolved by prosthetic obturation, autologous tissue reconstruction, or a combination of both. However, there is still controversy in the selection of the optimal approach. Therefore, the aim of this study was to systematically review evidences comparing the performance of obturators and flaps in patients after maxillary oncological ablation. Both electronic and manual searching approaches were conducted to identify eligible evidence. Two reviewers independently assessed the risk of bias. In addition, the same reviewers independently extracted the data. Meta-analyses were performed using Revman 5.3, and best evidence synthesis was performed. Sixteen studies were included and a total of 528 participants were analyzed. All studies were assessed at low quality. Results of this meta-analysis showed weak evidence in the difference between obturators and flaps on the outcome regarding word intelligibility (P = 0.004) and masticatory efficiency (P = 0.002). However, no differences were detected regarding speech intelligibility and nasalance. All studies were compiled into the best evidence synthesis. The sum of 31 evidences was considered. Twelve evidences were evaluated at a moderate level, such as speech, mastication, pain, salivation, taste sensations, and mouth opening. Except the outcomes of word intelligibility, masticatory efficiency, and mouth pain, other moderate evidences showed no difference between obturators and flaps. In conclusion, both obturators and flaps might be effective in patients' rehabilitation functions after maxillary ablation. However, some advantages were observed when using surgical reconstruction over prosthetic rehabilitation. Additional high-quality studies are needed to provide more solid evidence before applying these results into clinical practice.

Computer-assisted resection and reconstruction of bilateral osteoradionecrosis of the mandible using 2 separate flaps prepared from a single fibula

OBJECTIVES

Osteoradionecrosis of the mandible is a late radiation-induced complication, which is a major concern in survivors of head and neck cancer.

STUDY DESIGN

In this study, we present a case of a patient with nasopharyngeal carcinoma who developed extensive bilateral osteoradionecrosis of the ascending ramus of the mandible. After preoperative virtual surgical planning, the obtained data were used to fabricate patient-specific cutting templates. The bilateral mandibular defects were reconstructed using 2 separate flaps prepared from a single fibula.

RESULTS

Both defects were successfully reconstructed, and satisfactory aesthetic and functional results were achieved.

CONCLUSIONS

Bilateral mandibular osteoradionecrosis can be managed with virtual surgical planning, and the defects can be reconstructed using 2 separate flaps prepared from a single fibula.

Fibular osteofasciocutaneous flap in computer-assisted mandibular reconstruction: technical aspects in oral malignancies

Virtual surgical planning technology in head and neck surgery is witnessing strong growth. In the literature, the validity of the method from the point of view of accuracy and clinical utility has been widely documented, especially for bone modelling. To date, however, with its increased use in head and neck oncology, and consequently the increased need for bone and soft tissue reconstruction, is important to carry out the virtual programme considering not only bone reconstruction but also all aspects related to the reconstruction of soft tissue using composite flaps. We describe our approach to virtual planning in the case of composite flaps. The study reports six consecutive patients with malignant disease requiring mandibular bone and soft tissue reconstruction using fibular osteocutaneous flaps. In all six patients, the resection and reconstruction were planned virtually focusing on the position of cutaneous perforator vessels in order to schedule fibula cutting guides. There were no complications in all six cases. The technique described allowed us to schedule composite fibula flaps in mandibular reconstruction virtually with good accuracy of the position of the bone segment in relation to the cutaneous paddle, important for soft tissue reconstruction. Despite the limited number of cases, the preliminary results of the study suggest that this protocol is useful in virtual programmes using composite flaps in mandibular reconstruction. Further investigations are needed.

Application of Digital Diagnosis and Treatment Technique in Benign Mandibular Diseases

PURPOSE

To explore the feasibility of preoperative planning for treatment of benign mandibular lesions (BML) using digital technologies such as three-dimensional (3D) reconstruction, measurement, visualization as well as image contrast and design of neural positioning protection template (NPPT) in combination with 3D printing technology in the BML diagnosis and treatment.

METHODS

The 3D models of BML and inferior alveolar nerves (IAN) of 10 BML patients were reconstructed based on their digital imaging and communications in medicine (DICOM) data using MIMICS16.0 software. The models were used to visualize lesions and nerve contrast measurement and guide design of personalized NPPT and osteotomy after operation modality was determined in order to achieve accurate, minimally invasive operation with shortened intraoperative time.

RESULTS

Intraoperative NPPT application could accurately locate lesions and their scope and assist osteotomy. The measurement results were consistent with those of preoperative reconstruction and measurement. The BML were curetted completely without damage IAN. The 10 BML patients had no numbness and other discomforts in the lower lip and mandibular teeth after operation.

CONCLUSIONS

The digital diagnosis and treatment technology is an effective method for functional treatment of BML patients and its application could achieve personalized, minimally invasive and precise treatment and save intraoperation time.

Midface Fracture Simulation and Repair: A Computer-Based Algorithm

We introduce a novel computer-based method to digitally fixate midfacial fractures to facilitate more efficient intraoperative fixation. This article aims to describe a novel computer-based algorithm that can be utilized to model midface fracture reduction and fixation and to evaluate the algorithm's ability to produce images similar to true postoperative images. This is a retrospective review combined with cross-sectional survey from January 1, 2010, to December 31, 2015. This study was performed at a single tertiary care, level-I trauma center. Ten patients presenting with acute midfacial traumatic fractures were evaluated. Thirty-five physicians were surveyed regarding the accuracy of the images obtained using the algorithm. A computer algorithm utilizing AquariusNet (TeraRecon, Inc., Foster City, CA) and Adobe Photoshop (Adobe Systems Inc., San Jose, CA) was developed to model midface fracture repair. Preoperative three-dimensional computed tomographic (CT) images were processed using the algorithm. Fractures were virtually reduced and fixated to generate a virtual postoperative image. A survey comparing the virtual postoperative and the actual postoperative images was produced. A Likert-type scale rating system of 0 to 10 (0 being completely different and 10 being identical) was utilized. Survey participants evaluated the similarity of fracture reduction and fixation plate appearance. The algorithm's capacity for future clinical utility was also assessed. Survey response results from 35 physicians were collected and analyzed to determine the accuracy of the algorithm. Ten patients were evaluated. Fracture types included zygomaticomaxillary complex, LeFort, and naso-orbito-ethmoidal complex. Thirty-four images were assessed by a group of 35 physicians from the fields of otolaryngology, oral and maxillofacial surgery, and radiology. Mean response for fracture reduction similarity was 7.8 ± 2.5 and fixation plate similarity was 8.3 ± 1.9. All respondents reported interest in the tool for clinical use. This computer-based algorithm is able to produce virtual images that resemble actual postoperative images. It has the ability to model midface fracture repair and hardware placement.

Intraoperative Change in Defect Size during Maxillary Reconstruction Using Surgical Guides Created by CAD/CAM

Supplemental Digital Content is available in the text.

Surgical osteotomy guides created by computer-aided design/computer-aided manufacturing (CAD/CAM) have been developed and are now widely used in maxillofacial reconstruction. However, there are no standard procedures for dealing with an intraoperative change in defect size. We report on a case in which we used our CAD/CAM guides to deal with an intraoperative change in defect size in a maxillary reconstruction. We planned the maxillary reconstruction using a free fibula flap because of left maxillary sinus cancer in a 73-year-old man. In Japan, we cannot use commercially supplied CAD/CAM guides because these have not been approved by the government. We created novel CAD/CAM guides by using free software and a low-cost 3D printer. We performed model surgery to check the accuracy of the design and to prebend the titanium plates before the operation. The actual defect in the maxilla was found to be smaller than that used in preoperative planning. It was therefore necessary to rearrange the fibular segments and to rebend the plates. Comparison between the preoperative and postoperative 3D images showed that the deviation was 2–4 mm. In case that the CAD/CAM guides become inapplicable because of an intraoperative change in defect size, rearranging both the ends of set-up fibular segments and rebending the plates in situ allows us to deal with the situation. However, because extra time is needed to rearrange and rebend, the total operation and flap ischemic times are not shortened.

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

PURPOSE

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.

MATERIALS AND METHODS

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.

RESULT

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.

CONCLUSION

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.

The use of virtual surgical planning and navigation in the treatment of orbital trauma

Virtual surgical planning (VSP) has recently been introduced in craniomaxillofacial surgery with the goal of improving efficiency and precision for complex surgical operations. Among many indications, VSP can also be applied for the treatment of congenital and acquired craniofacial defects, including orbital fractures. VSP permits the surgeon to visualize the complex anatomy of craniofacial region, showing the relationship between bone and neurovascular structures. It can be used to design and print using three-dimensional (3D) printing technology and customized surgical models. Additionally, intraoperative navigation may be useful as an aid in performing the surgery. Navigation is useful for both the surgical dissection as well as to confirm the placement of the implant. Navigation has been found to be especially useful for orbit and sinus surgery. The present paper reports a case describing the use of VSP and computerized navigation for the reconstruction of a large orbital floor defect with a custom implant.