Accurate reconstruction of bone defects in orbital-maxillary-zygomatic (OMZ) complex with polyetheretherketone (PEEK)

Correction of Secondary Exophthalmos Caused by Lateral Orbital Rim Recession: Add-on Implants Through a 3D Approach

ABSTRACT

Improving exophthalmos is a crucial aspect of treatment for patients with syndromic craniosynostosis. However, in patients who have undergone previous treatments including fronto-orbital advancement and Le Fort III distraction osteogenesis and who have reached skeletal maturity, the recurrence of exophthalmos is not uncommon. The severity of the exophthalmos may vary. Whether secondary correction involving osteotomy should be performed or symptomatic treatment strategies should be adopted is a dilemma, and the patient's symptoms and background and the invasiveness of the surgery should also be considered. Additionally, the accurate measurement and treatment of exophthalmos require the expertise of surgeons. This report introduces self-developed orbital wall implants generated through 3-dimensional simulation and 3-dimensional printing. The patient was a 23-year-old woman with Crouzon syndrome and recurrent exophthalmos. After surgery, the exophthalmos and facial appearance were improved. The use of custom-made implants provides advantages over the conventional osteotomy method; it is less invasive, involves a simple surgical procedure, and offers cost and time savings.

A comprehensive review on the State of the Art in the research and development of poly-ether-ether-ketone (PEEK) biomaterial-based implants

Polyetheretherketone (PEEK) is a preferred high-performance polymer in the spine, orthopedic, and craniomaxillofacial implant industry. However, despite its commendable mechanical properties, its bioinert nature limits the implants from integrating with neighboring tissues, impacting the implant's long-term performance. To address this limitation, various kinds of surface functionalization techniques have been developed over the years. Noteworthy efforts have been made to incorporate bioactive fillers in the PEEK matrix to develop standalone bioactive composites. In personalized medicine, significant advances have been made in the 3D Printing of PEEK implants. 3D-printed PEEK implants are now being developed at Point-of-Care, significantly reducing manufacturing and logistic time. Given the recent clinical follow-up updates and advancements in PEEK-based implants, PEEK implants are witnessing an important phase in its history. Recognizing this vital phase, this paper aims to comprehensively review the advancements of PEEK implants over the past decade. The review starts with an overview of the clinical impact of varying PEEK implants, followed by PEEK's surface functionalization techniques and engineering of PEEK-based bioactive composites. Next, this review describes the advancements made in the 3D printing of PEEK implants and points out the essential considerations that should be considered when developing 3D-printed PEEK-based implants. Finally, the review ends with an estimated projection about the future of PEEK-based implants. Readers are expected to gain an all-encompassing and in-depth understanding of PEEK biomedical implants' past, present, and future, enabling researchers to advance the research and development of PEEK-based implants in the required direction. STATEMENT OF SIGNIFICANCE: PEEK is a preferred high-performance polymer in the implant industry, with notable benefits over metallic and ceramic implants, such as bone-matching stiffness and durability. Significant strides have been made in the last decade to make PEEK implants bioactive and utilize 3D Printing to develop patient-specific implants. Given the recent advancements in PEEK-based implants, this review aims to provide an all-encompassing and in-depth understanding of PEEK biomedical implants' past, present, and future. It will comprehensively discuss the know-how gained from the clinical follow-up, the strategies to address the limitations of PEEK implants, and the essential considerations in 3D Printing of PEEK implants. This review will enable researchers to advance the research and development of PEEK implants in the required direction.

A method for accuracy of placement analysis on radiolucent polyether-ether-keton facial implants: A case series

Facial asymmetry is defined as a bilateral difference between facial components. Correction, often desired by the patient, can be performed with the aim of bone born patient-specific solid implants designed using 3D CAD software. This treatment is embedded in the daily practice of today's healthcare. However, an analysis of the implant's accuracy of placement has not been reported. This case series describes the accuracy analysis of bone born aesthetic facial implants manufactured out of polyether-ether-ketone (PEEK). The accuracy analysis was based on postoperative (cone beam) computed tomography ((CB)CT) data and preoperative 3D planning. The analysis showed a median entry point error of 0.7 mm (min: 0.1, max: 3.3, interquartile range: 0.78). The median maximal orientation error was 5.5° (min: 0.1, max: 36.8, interquartile range: 7.13). Both parameters showed an excellent intraobserver and interobserver agreement with an ICC above 0.84. The described cases show that the analysis method is an objective approach for determining the accuracy of PSI placement and indicates that these implants can be placed accurately on the osseous face.

Gender Affirming Facial Surgery-Anatomy and Procedures for Facial Masculinization

For some patients, feminine facial features may cause significant gender dysphoria. Multiple nonsurgical and surgical techniques exist to masculinize facial features. Nonsurgical techniques include testosterone supplementation and dermal fillers. Surgical techniques include soft tissue manipulation, synthetic implants, regenerative scaffolding, or bony reconstruction. Many techniques are derived from experience with cisgender patients, but are adapted with special considerations to differing anatomy between cisgender and transgender men and women. Currently, facial masculinization is less commonly sought than feminization, but demand is likely to increase as techniques are refined and made available.

Custom CAD/CAM Peek Implants for Complex Orbitocranial Reconstruction: Our Experience with 15 Patients

Bone defects within the cranio-orbital complex present unique challenges in terms of surgical planning and reconstruction. This article presents a novel approach using PEEK material and advanced surgical technologies to address these challenges. A retrospective analysis of 15 patients who underwent craniofacial reconstruction using patient-specific polyetheretherketone (PEEK) implants between 2016 and 2021 was carried out. Comprehensive preoperative planning was performed, utilizing advanced imaging techniques and specialized software for virtual surgical planning. Patient-specific PEEK PSIs were designed and manufactured based on the preoperative plan. Intraoperative navigation was used to guide the surgical procedure, enabling precise osteotomy and optimal implant placement. This article describes the step-by-step process and the tools utilized in each phase. The etiologies were as follows: meningioma in seven cases, benign lesions in five cases, malignant tumors in two cases, and trauma sequelae in one case. In all cases, 3D-printed PEEK implants were utilized to achieve precise reconstruction. No major complications were described. In one case, an implant replacement was needed with successful outcomes. Our study demonstrates the feasibility and effectiveness of using PEEK patient-specific implants for personalized craniofacial reconstruction. The combination of advanced imaging, virtual planning, and CAD-CAM technology contributes to improved surgical outcomes in terms of oncologic margin control, functional restoration, and aesthetic results.

Customed 3D-printed Polyetheretherketone (PEEK) Implant for Secondary Salvage Reconstruction of Mandibular Defects: Case Report and Literature Review

Given the insufficient height of single-barrel fibula and inadequate bone volume of double-barrel vascularized fibula in mandibular reconstruction, it is a better choice to combine the upper full-thickness vascularized fibula with the lower half-thickness nonvascularized fibula. However, the nonvascularized fibula may fail due to complications, affecting the facial shape and occlusal function. Polyetheretherketone is a thermoplastic polymer used for bone defect reconstruction due to its good mechanical properties and biocompatibility. This case report mainly presents a secondary salvage reconstruction of the mandible by using customed 3-dimensional-printing polyetheretherketone, which restored the continuity and symmetry of the mandible, improved the patient's facial shape, and restored functional occlusion through dental implants. After a 28-month follow-up, no complications occurred, and the patient was satisfied with the final restoration.

Advances and Prospects in Materials for Craniofacial Bone Reconstruction

The craniofacial region is composed of 23 bones, which provide crucial function in keeping the normal position of brain and eyeballs, aesthetics of the craniofacial complex, facial movements, and visual function. Given the complex geometry and architecture, craniofacial bone defects not only affect the normal craniofacial structure but also may result in severe craniofacial dysfunction. Therefore, the exploration of rapid, precise, and effective reconstruction of craniofacial bone defects is urgent. Recently, developments in advanced bone tissue engineering bring new hope for the ideal reconstruction of the craniofacial bone defects. This report, presenting a first-time comprehensive review of recent advances of biomaterials in craniofacial bone tissue engineering, overviews the modification of traditional biomaterials and development of advanced biomaterials applying to craniofacial reconstruction. Challenges and perspectives of biomaterial development in craniofacial fields are discussed in the end.

Polyetheretherketone development in bone tissue engineering and orthopedic surgery

Polyetheretherketone (PEEK) has been widely used in the medical field as an implant material, especially in bone tissue engineering and orthopedic surgery, in recent years. This material exhibits superior stability at high temperatures and is biosecured without harmful reactions. However, the chemical and biological inertness of PEEK still limits its applications. Recently, many approaches have been applied to improve its performance, including the modulation of physical morphology, chemical composition and antimicrobial agents, which advanced the osteointegration as well as antibacterial properties of PEEK materials. Based on the evolution of PEEK biomedical devices, many studies on the use of PEEK implants in spine surgery, joint surgery and trauma repair have been performed in the past few years, in most of which PEEK implants show better outcomes than traditional metal implants. This paper summarizes recent studies on the modification and application of biomedical PEEK materials, which provides further research directions for PEEK implants.

A Case Report of Zygomatic Fracture Reconstruction: Evaluation with Orbital Measurements and Models Registration

The repair and reconstruction of defects in the craniomaxillofacial region can be particularly challenging due to the complex anatomy, individuality of each defect, and sensitivity of the involved systems. This study aims to enhance the facial appearance and contribute to the reconstruction of the zygomatic arch. This was achieved through virtual planning of the surgery and assessment of clinical matching, including orbital measurements and registration of numerical models. A three-dimensional design of a young female case was generated on a skull model using Mimics® software, and the orbit was isolated using 3-Matic® to assess the reconstructive effect. 3D-printed implants were then surgically placed on the injured region, and Netfabb® software was used to make a virtual registration between the numerical models before and after the intervention. This allowed for the calculation of a deviation of 7 mm, equivalent to 86.23% of the shape restoration rate, to assess the success of the surgery. The computerized method enabled a precise design of the needed plates and analysis of the fixation places, resulting in a satisfactory cosmetic and functional outcome for the patient with minimal complications and good implant stability. Notably, a significant difference was observed in the orbital frontal area after 3 months of surgery (p < 0.001). Within the limitations of the study, these results suggest that virtual planning and customized titanium implants can serve as useful tools in the management of complex zygomatic-orbital injuries.

[Domestic software, medical devices and materials in surgery for hyperostotic craniofacial meningiomas]

OBJECTIVE

The modern concept of resection of hyperostotic craniofacial meningiomas involves the desire for one-stage surgery with excision of tumor and simultaneous extensive skull defect closure.

MATERIAL AND METHODS

The authors present skull defect closure with an individual implant after resection of cranioorbital meningioma in a 61-year-old man. The neoplasm was accompanied by exophthalmos and eyelid edema. The patient underwent simultaneous microsurgical resection and skull reconstruction with an individual implant. At discharge (7 days after surgery), exophthalmos regressed to 3 mm. After 3 months, ophthalmologist revealed complete regression of exophthalmos.

RESULTS

Domestic software and 3D printers were used for implant modeling and preparing the necessary physical models and molds. We intraoperatively used domestic polymer and titanium fixation systems for manufacturing and fixation of implant.

CONCLUSION

This clinical case confirms that resection of hyperostotic craniofacial meningioma with simultaneous bone defect closure using domestic analogues of software, technical equipment, materials and methods is possible at all stages of this procedure.