Design, Analysis, and 3D Printing of a Patient-Specific Polyetheretherketone Implant for the Reconstruction of Zygomatic Deformities

Optimizing group work strategies in virtual dissection

Due to its haptic and interactive nature, virtual anatomy provides an opportunity for small-group learning, enabling students to develop their group work skills before they graduate. However, there is currently little practical guidance supported by pedagogic principles detailing how to incorporate it into curricula. Anatomy educators at the University of Plymouth conducted action research aiming to capture students' overall perceptions of the virtual anatomy platform Anatomage. Questioning the benefits and challenges students face while interacting with Anatomage prompted the creation of evidence-based interventions to be later evaluated. Although a plethora of themes were identified, this report specifically examines those relating to group work. Thematic analysis of initial focus group data found group size and group dynamics impacted students' experience with the platform. Following the implementation of interventions to resolve these issues, a questionnaire and second series of focus groups were conducted to determine whether they were successful. Additional subthemes found from these data included facilitation, social pressure, peer learning and working with friends. This study contributed to the improvement of small group learning and integration of virtual anatomy into curricula based on student and staff feedback. As such, these data support the development of effective group working skills which are fundamental for healthcare professionals and widely recognized by regulators such as the General Medical Council and Health and Care Professions Council. In this report, the authors provide practical advice informed by pedagogy and principles from management and psychology to provide a multidisciplinary perspective.

Endoscopic-Assisted Forehead Augmentation with Polyetheretherketone (PEEK) Patient-Specific Implant (PSI) for Aesthetic Considerations

BACKGROUND

Forehead augmentation have become popular aesthetic procedures among Asians in recent years. However, the use of polyetheretherketone (PEEK) patient-specific implant (PSI) in the facial contouring surgery for aesthetic considerations is not well documented in the existing studies. The purpose of this study was to develop a novel method for forehead augmentation and assess the clinical outcomes and complications in patients who underwent forehead augmentation with PEEK PSI assisted by endoscopy.

METHODS

The PEEK PSIs were fabricated using the virtual surgical planning (VSP) and the computer-aided manufacturing (CAM) for each patient, preoperatively. The implant pockets were dissected in the subperiosteal plane, and PEEK PSIs were placed in their designed position and fixed assisting by endoscopy via small incision within the hairline. All patients were asked to complete the FACE-Q questionnaire before and 6 months after the operation. Pre- and postoperative demographics, photographs, and other clinical data of patients were collected and analyzed.

RESULTS

11 patients underwent forehead augmentation were enrolled in this study. All procedures were completed successfully with the help of endoscope. The average patient age was 30.63 ± 2.54 years. The mean thickness and size of PEEK PSI were 4.44 ± 1.77 mm and 38.43 ± 22.66 cm2, respectively. The mean operative time was 83.00 ± 29.44 min, and the mean postoperative follow-up period was 11.00 ± 6.50 months. No implant exposure, extrusion or removal were reported. The FACE-Q scores of patients in satisfaction with the forehead increased from 47.64 ± 7.15 to 78.81 ± 6.35.

CONCLUSIONS

PEEK PSIs can be prefabricated to achieve accurate remodeling of the frontal contour with good esthetic outcomes. The endoscope provides direct and magnified vision, which allow easy access to the supraorbital rim and lateral edge of the eyebrow arch and confirming the position of the implants without damaging nerves and vessels. Endoscopic-assisted forehead augmentation with PEEK PSI is safe and effective.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of contents or the online Instructions to Authors www.springer.com/00266 .

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.

The Utility of 3D Printing for Surgical Planning and Patient-Specific Implant Design in Maxillofacial Surgery: A Narrative Review

Maxillofacial reconstructive implants are typically created in standard shapes and have a widespread application in head and neck surgery. During surgical procedures, the implant must be correctly bent according to the architecture of the particular bones. Bending takes practice, especially for untrained surgeons. Furthermore, repeated bending may increase internal stress, resulting in fatigue in vivo under masticatory loading and an array of consequences, including implant failure. There is a risk of fracture, screw loosening, and bone resorption. Resorption, infection, and displacement are usually associated with the use of premade alloplastic implants and autogenous grafts. Recent technological breakthroughs have led to the use of patient-specific implants (PSIs) developed by computer-designed additive manufacturing in reconstructive surgery. The use of computer-designed three-dimensional (3D)-printed PSI allows for more precise restoration of maxillofacial deformities, avoiding the common difficulties associated with premade implants and increasing patient satisfaction. Additive manufacturing is something that refers to a group of additive manufacturing methods. This technique has been quickly used in a variety of surgical procedures. The exponential expansion of this technology can be attributed to its enormous surgical value. Adding 3D printing to a medical practice can be a rewarding experience with stunning results.

The Progress in Bioprinting and Its Potential Impact on Health-Related Quality of Life

The intensive development of technologies related to human health in recent years has caused a real revolution. The transition from conventional medicine to personalized medicine, largely driven by bioprinting, is expected to have a significant positive impact on a patient's quality of life. This article aims to conduct a systematic review of bioprinting's potential impact on health-related quality of life. A literature search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive literature search was undertaken using the PubMed, Scopus, Google Scholar, and ScienceDirect databases between 2019 and 2023. We have identified some of the most significant potential benefits of bioprinting to improve the patient's quality of life: personalized part production; saving millions of lives; reducing rejection risks after transplantation; accelerating the process of skin tissue regeneration; homocellular tissue model generation; precise fabrication process with accurate specifications; and eliminating the need for organs donor, and thus reducing patient waiting time. In addition, these advances in bioprinting have the potential to greatly benefit cancer treatment and other research, offering medical solutions tailored to each individual patient that could increase the patient's chance of survival and significantly improve their overall well-being. Although some of these advancements are still in the research stage, the encouraging results from scientific studies suggest that they are on the verge of being integrated into personalized patient treatment. The progress in bioprinting has the power to revolutionize medicine and healthcare, promising to have a profound impact on improving the quality of life and potentially transforming the field of medicine and healthcare.

Optimization and manufacture of polyetheretherketone patient specific cranial implants by material extrusion - A clinical perspective

Polyetheretherketone (PEEK) is a high performing thermoplastic that has established itself as a 'gold-standard' material for cranial reconstruction. Traditionally, milled PEEK patient specific cranial implants (PSCIs) exhibit uniform levels of smoothness (excusing suture/drainage holes) to the touch (<1 μm) and homogenous coloration throughout. They also demonstrate predictable and repeatable levels of mechanical performance, as they are machined from isotropic material blocks. The combination of such factors inspires confidence from the surgeon and in turn, approval for implantation. However, manufacturing lead-times and affiliated costs to fabricate a PSCI are high. To simplify their production and reduce expenditure, hospitals are exploring the production of in-house PEEK PSCIs by material extrusion-based additive manufacturing. From a geometrical and morphological perspective, such implants have been produced with good-to-satisfactory clinical results. However, lack of clinical adoption persists. To determine the reasoning behind this, it was necessary to assess the benefits and limitations of current printed PEEK PSCIs in order to establish the status quo. Afterwards, a review on individual PEEK printing variables was performed in order to identify a combination of parameters that could enhance the aesthetics and performance of the PSCIs to that of milled implants/cranial bone. The findings from this review could be used as a baseline to help standardize the production of PEEK PSCIs by material extrusion in the hospital.

Biomechanical Effects of the Porous Structure of Gyroid and Voronoi Hip Implants: A Finite Element Analysis Using an Experimentally Validated Model

Total hip arthroplasty (THA) is most likely one of the most successful surgical procedures in medicine. It is estimated that three in four patients live beyond the first post-operative year, so appropriate surgery is needed to alleviate an otherwise long-standing suboptimal functional level. However, research has shown that during a complete THA procedure, a solid hip implant inserted in the femur can damage the main arterial supply of the cortex and damage the medullary space, leading to cortical bone resorption. Therefore, this study aimed to design a porous hip implant with a focus on providing more space for better osteointegration, improving the medullary revascularisation and blood circulation of patients. Based on a review of the literature, a lightweight implant design was developed by applying topology optimisation and changing the materials of the implant. Gyroid and Voronoi lattice structures and a solid hip implant (as a control) were designed. In total, three designs of hip implants were constructed by using SolidWorks and nTopology software version 2.31. Point loads were applied at the x, y and z-axis to imitate the stance phase condition. The forces represented were x = 320 N, y = -170 N, and z = -2850 N. The materials that were used in this study were titanium alloys. All of the designs were then simulated by using Marc Mentat software version 2020 (MSC Software Corporation, Munich, Germany) via a finite element method. Analysis of the study on topology optimisation demonstrated that the Voronoi lattice structure yielded the lowest von Mises stress and displacement values, at 313.96 MPa and 1.50 mm, respectively, with titanium alloys as the materials. The results also indicate that porous hip implants have the potential to be implemented for hip implant replacement, whereby the mechanical integrity is still preserved. This result will not only help orthopaedic surgeons to justify the design choices, but could also provide new insights for future studies in biomechanics.

Can Steam Sterilization Affect the Accuracy of Point-of-Care 3D Printed Polyetheretherketone (PEEK) Customized Cranial Implants? An Investigative Analysis

Polyetheretherketone (PEEK) has become the biomaterial of choice for repairing craniofacial defects over time. Prospects for the point-of-care (POC) fabrication of PEEK customized implants have surfaced thanks to the developments in three-dimensional (3D) printing systems. Consequently, it has become essential to investigate the characteristics of these in-house fabricated implants so that they meet the necessary standards and eventually provide the intended clinical benefits. This study aimed to investigate the effects of the steam sterilization method on the dimensional accuracy of POC 3D-printed PEEK customized cranial implants. The objective was to assess the influence of standard sterilization procedures on material extrusion-based 3D-printed PEEK customized implants with non-destructive material testing. Fifteen PEEK customized cranial implants were fabricated using an in-house material extrusion-based 3D printer. After fabrication, the cranial implants were digitalized with a professional-grade optical scanner before and after sterilization. The dimensional changes for the 3D-printed PEEK cranial implants were analyzed using medically certified 3D image-based engineering software. The material extrusion 3D-printed PEEK customized cranial implants displayed no statistically significant dimensional difference with steam sterilization (p > 0.05). Evaluation of the cranial implants’ accuracy revealed that the dimensions were within the clinically acceptable accuracy level with deviations under 1.00 mm. Steam sterilization does not significantly alter the dimensional accuracy of the in-house 3D-printed PEEK customized cranial implants.