Virtual surgical planning and 3D printing in prosthetic orbital reconstruction with percutaneous implants: a technical case report

Exploring digital technologies used in the design and manufacture of craniofacial implant surgical guides: A scoping review

STATEMENT OF PROBLEM

Unlike intraoral implants, digitally planned surgical templates used for guiding the ideal position of the craniofacial implants are not well established, and clear methods and guidelines for their design and construction are lacking.

PURPOSE

The purpose of this scoping review was to identify the publications that used a full or partial computer-aided design and computer-aided manufacture (CAD-CAM) protocol to create a surgical guide that achieves the correct positioning of craniofacial implants to retain a silicone facial prosthesis.

MATERIAL AND METHODS

A systematic search was conducted in MEDLINE/PubMed, Web of Science, Embase, and Scopus for articles published before November 2021 in the English language. Articles needed to satisfy the eligibility criterion of in vivo articles that created a surgical guide with digital technology for inserting titanium craniofacial implants to hold a silicone facial prosthesis. Articles that inserted implants in the oral cavity or upper alveolus only and articles that did not describe the structure and retention of the surgical guide were excluded.

RESULTS

Ten articles were included in the review; all were clinical reports. Two of the articles used a CAD-only approach alongside a conventionally constructed surgical guide. Eight articles described applying a complete CAD-CAM protocol for the implant guides. The digital workflow varied considerably depending on the software program, design, and retention of guides. Only 1 report described a follow-up scanning protocol to verify the accuracy of the final implant positions compared with the planned positions.

CONCLUSIONS

Digitally designed surgical guides can be an excellent adjunct to accurately place titanium implants in the craniofacial skeleton for support of silicone prostheses. A sound protocol for the design and retention of the surgical guides will enhance the use and accuracy of craniofacial implants in prosthetic facial rehabilitation.

Towards Precision Ophthalmology: The Role of 3D Printing and Bioprinting in Oculoplastic Surgery, Retinal, Corneal, and Glaucoma Treatment

In the forefront of ophthalmic innovation, biomimetic 3D printing and bioprinting technologies are redefining patient-specific therapeutic strategies. This critical review systematically evaluates their application spectrum, spanning oculoplastic reconstruction, retinal tissue engineering, corneal transplantation, and targeted glaucoma treatments. It highlights the intricacies of these technologies, including the fundamental principles, advanced materials, and bioinks that facilitate the replication of ocular tissue architecture. The synthesis of primary studies from 2014 to 2023 provides a rigorous analysis of their evolution and current clinical implications. This review is unique in its holistic approach, juxtaposing the scientific underpinnings with clinical realities, thereby delineating the advantages over conventional modalities, and identifying translational barriers. It elucidates persistent knowledge deficits and outlines future research directions. It ultimately accentuates the imperative for multidisciplinary collaboration to enhance the clinical integration of these biotechnologies, culminating in a paradigm shift towards individualized ophthalmic care.

Virtual surgical planning in craniomaxillofacial surgery: a structured review

Craniomaxillofacial (CMF) surgery is a challenging and very demanding field that involves the treatment of congenital and acquired conditions of the face and head. Due to the complexity of the head and facial region, various tools and techniques were developed and utilized to aid surgical procedures and optimize results. Virtual Surgical Planning (VSP) has revolutionized the way craniomaxillofacial surgeries are planned and executed. It uses 3D imaging computer software to visualize and simulate a surgical procedure. Numerous studies were published on the usage of VSP in craniomaxillofacial surgery. However, the researchers found inconsistency in the previous literature which prompted the development of this review. This paper aims to provide a comprehensive review of the findings of the studies by conducting an integrated approach to synthesize the literature related to the use of VSP in craniomaxillofacial surgery. Twenty-nine related articles were selected as a sample and synthesized thoroughly. These papers were grouped assigning to the four subdisciplines of craniomaxillofacial surgery: orthognathic surgery, reconstructive surgery, trauma surgery and implant surgery. The following variables - treatment time, the accuracy of VSP, clinical outcome, cost, and cost-effectiveness - were also examined. Results revealed that VSP offers advantages in craniomaxillofacial surgery over the traditional method in terms of duration, predictability and clinical outcomes. However, the cost aspect was not discussed in most papers. This structured literature review will thus provide current findings and trends and recommendations for future research on the usage of VSP in craniomaxillofacial surgery.

The Latest Craniofacial Reconstructive Techniques Using Anchored Implants after Surgical Treatment of Nasal and Paranasal Sinuses Tumors

Reconstructive surgery after surgical treatment of neoplasms in the head and neck region is always a challenge. Many factors are responsible for the success of reconstruction. The anatomy of the facial region is complex, which significantly influences the aesthetic effect of the reconstruction. Moreover, many patients undergo postoperative radiotherapy after surgical treatment, which affects the range of reconstructive techniques. The aim of this study is to review current reconstructive methods in the craniofacial region, using bone-anchored implants to attach nasal prostheses. The article also comprises the authors' own experience with successful single-stage, Vistafix 3 osseointegrated implants for the attachment of an external nasal prosthesis in a 51-year-old man after surgical removal of squamous cell carcinoma of the nose and paranasal sinuses. The literature search for articles regarding implants in craniofacial reconstructions was performed using the three following databases: Scopus, Web of Science and MEDLINE (through PubMed), and follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement (PRISMA). A systematic literature search was set for 2018-2023 and retrieved 92 studies. From them, 18 articles were included in the review.

A Contemporary Review of the Role of Facial Prostheses in Complex Facial Reconstruction

BACKGROUND

Maxillofacial prostheses provide effective rehabilitation of complex facial defects as alternatives to surgical reconstruction. Although facial prostheses provide aesthetically pleasing reconstructions, multiple barriers exist that prevent their routine clinical use. The accessibility of facial prostheses is limited by the scarce supply of maxillofacial prosthodontists, significant time commitment and number of clinic appointments required of patients during prosthesis fabrication, short lifespan of prostheses, and limited outcomes data.

METHODS

A literature review was completed using PubMed and Embase databases, with search phrases including face and maxillofacial prostheses. Patient cases are included to illustrate the use of facial prostheses to reconstruct complex facial defects.

RESULTS

The clinical use of facial prostheses requires a multidisciplinary team including a reconstructive surgeon, a maxillofacial prosthodontist, and an anaplastologist, if available, to provide patients with aesthetically appropriate facial prostheses. Developing technology including computer-aided design and three-dimensional printing may improve the availability of facial prostheses by eliminating multiple steps during prosthesis fabrication, ultimately decreasing the time required to fabricate a prosthesis. In addition, enhanced materials may improve prosthesis durability. Long-term outcomes data using validated measures is needed to support the continued use of facial prostheses.

CONCLUSIONS

Facial prostheses can be used to reconstruct complex facial defects, and bone-anchored prostheses are associated with high patient satisfaction. Multiple barriers prevent prostheses from being used for facial reconstruction. New technologies to assist the design and fabrication of prostheses, and cost reduction measures, may allow their use in the appropriately selected patient.

3D printing for surgical planning of canine oral and maxillofacial surgeries

Background

Advanced diagnostic imaging is an essential part of preoperative planning for oral and maxillofacial surgery in veterinary patients. 3-dimensional (3D) printed models and surgical guides generated from diagnostic imaging can provide a deeper understanding of the complex maxillofacial anatomy, including relevant spatial relationships. Additionally, patient-specific 3D printed models allow surgeons and trainees to better examine anatomical features through tactile and visuospatial feedback allowing for improved preoperative planning, intraoperative guidance, and enhanced trainee education. Furthermore, these models facilitate discussions with pet owners, allowing for improved owner understanding of pathology, and educated decision-making regarding treatment.

Case presentation

Our case series consists of three 3D printed models segmented from computed tomography (CT) and cone beam CT (CBCT) and fabricated via desktop vat polymerization for preoperative planning and intraoperative guidance for resection of maxillary osteosarcoma, mandibular reconstruction after mandibulectomy, and gap arthroplasty for temporomandibular joint ankylosis in dogs.

Conclusions

We illustrate multiple benefits and indications for 3D printing in veterinary oral and maxillofacial surgery. 3D printed models facilitate the understanding of complex surgical anatomy, creating an opportunity to assess the spatial relationship of the relevant structures. It facilitates individualized surgical planning by allowing surgeons to tailor and augment the surgical plan by examining patient-specific anatomy and pathology. Surgical steps may also be simulated in advance, including planning of osteotomy lines, and pre-contouring of titanium plates for reconstruction. Additionally, a 3D printed model and surgical guide also serve as invaluable intraoperative reference and guidance. Furthermore, 3D printed models have the potential to improve veterinary resident and student training as well as pet owner understanding and communication regarding the condition of their pets, treatment plan and intended outcomes.

3D Printing in Eye Care

Three-dimensional printing enables precise modeling of anatomical structures and has been employed in a broad range of applications across medicine. Its earliest use in eye care included orbital models for training and surgical planning, which have subsequently enabled the design of custom-fit prostheses in oculoplastic surgery. It has evolved to include the production of surgical instruments, diagnostic tools, spectacles, and devices for delivery of drug and radiation therapy. During the COVID-19 pandemic, increased demand for personal protective equipment and supply chain shortages inspired many institutions to 3D-print their own eye protection. Cataract surgery, the most common procedure performed worldwide, may someday make use of custom-printed intraocular lenses. Perhaps its most alluring potential resides in the possibility of printing tissues at a cellular level to address unmet needs in the world of corneal and retinal diseases. Early models toward this end have shown promise for engineering tissues which, while not quite ready for transplantation, can serve as a useful model for in vitro disease and therapeutic research. As more institutions incorporate in-house or outsourced 3D printing for research models and clinical care, ethical and regulatory concerns will become a greater consideration. This report highlights the uses of 3D printing in eye care by subspecialty and clinical modality, with an aim to provide a useful entry point for anyone seeking to engage with the technology in their area of interest.

3D printing advances in the development of stents

3D printing technologies have found several applications within the biomedical sector including in the fabrication of medical devices, advanced visualization, diagnosis planning and simulation of surgical procedures. One of the areas in which of 3D printing is anticipated to revolutionised is the manufacturing of implantable bioresorbable drug-eluting scaffolds (stents). The ability to customize and create personalised tailor-made bioresorbable scaffolds has the potential to help solve many of the challenges associated with stenting, such as inappropriate stent sizing and design, abolish late stent thrombosis and help artery growth; 3D printing offers a rapid prototyping and effective method of producing stents making customization of designs feasible. This review provides an overview of the subjects and summarizes the latest research in the 3D printing technologies employed for the design and fabrication of bioresorbable stents including materials with the required printable and mechanical properties. Finally, we present a regulatory perspective on the development and engineering of 3D printed implantable stents.

Systematic Review of Clinical Applications of CAD/CAM Technology for Craniofacial Implants Placement and Manufacturing of Orbital Prostheses

This systematic review was aimed at gathering technical and clinical applications of CAD/CAM technology for the preoperative planning of craniofacial implants placement, designing of molds and substructures and fabrication of orbital prostheses. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, an electronic search was executed. Human studies that utilized digital planning systems for the prosthetic rehabilitation of orbital defects were included. A total of 16 studies of 30 clinical cases, which were virtually planned through various digital planning and designing software, were included. The most common preoperative data required for digital planning were CT scans in 15 cases, the 3DSS-STD-II scanning system in 5 cases, an Artec Color 3D scanner in 3 cases and a NextEngine Desktop 3D laser scanner in 2 cases. Meanwhile, the digital designing software were Ease Orbital Implant Planning EOIPlan software in eight cases, Geomagic software in eight cases, Simplant software in four cases and Artec Studio 12 Professional in three cases. Surgical templates were fabricated for 12 cases to place 41 craniofacial implants in the orbital defect area. An image-guided surgical navigation system was utilized for the placement of five orbital implants in two cases. Digital designing and printing systems were reported for the preoperative planning of craniofacial implants placement, designing of molds and substructures and fabrication of orbital prostheses. The studies concluded that the digital planning, designing and fabrication of orbital prostheses reduce the clinical and laboratory times, reduces patient visits and provide a satisfactory outcome; however, technical skills and equipment costs are posing limitations on the use of these digital systems.

Patient-Specific Implants in Oculofacial Plastic Surgery

PURPOSE

To investigate how patient-specific implants (PSIs) are being utilized for periocular facial skeletal reconstruction. Specifically, to characterize indications for custom implants, areas of reconstruction, intraoperative variables impacting implant placement, as well as to report on postoperative outcomes.

MATERIALS AND METHODS

A retrospective chart review was performed for patients who received a PSI for periocular skeletal reconstruction between 2015 and 2019. Three independent academic centers were included in this study, which encompassed 4 different primary surgeons. Medical records, radiographic imaging, and operative reports were reviewed.

RESULTS

Eleven patients, 8 females and 3 males, ages ranging from 15 to 63 years old received PSIs. The average duration of follow up was 16 months ± 6.6 months (range: 9-30 months). The most common underlying etiology for reconstruction was prior trauma (54.5%) followed by benign tumor resection (18.2%). The most frequent area of reconstruction involved the inferior orbital rim and adjacent maxilla (63.6%). Implant materials included porous polyethylene, polyetheretherketone, and titanium. Six implants required intraoperative modification, most commonly accommodate critical neurovascular structures (66.6%) or improve contour (33.3%). Two postoperative complications were noted, both in the form of infection with 1 implant requiring removal.

CONCLUSIONS

Reconstruction of complex facial skeletal defects can be achieved by utilizing computer-assisted design software and 3D printing techniques to create PSIs. These implants represent the most customizable option for symmetric restoration of the facial skeleton by not only addressing structural deficits but also volumetric loss. This was particularly apparent in reconstruction of the orbital rim and midface. PSIs were found to be of most benefit in patients with prior trauma or complex skeletal defects after tumor resection.

State of the Art Care in Computer-Assisted Facial Prosthetic Rehabilitation

ABSTRACT

Autologous reconstruction for major facial defects is primarily considered for patient's lifetime care. There are situations, however, when autologous reconstruction is not ideal or feasible, and prosthetic reconstruction is necessary to reconstruct missing anatomy or to complement surgical reconstruction. The history of facial prosthetic reconstruction can be traced for millennia. At our craniofacial center, craniomaxillofacial prosthetic rehabilitation has been incorporated in the care provided to our patients since the center's inception, more than 70 years ago.The purpose of this review is to present the evolution of our current thinking based on our long experience since the implementation of computer-assistive technologies over 15 years ago, to further improve our patients' overall rehabilitation.These applications include all stages of prosthetic care from planning, design through device delivery, and for lifetime maintenance. The collaboration among surgeons and anaplastologists is fundamental to achieving optimal patient outcomes and in the success of our technology-based practice. Such collaboration starts with the patient's decision to proceed with prosthetic rehabilitation and continues with postoperative care and lifetime management of the patient's prosthetic device and prosthesis-bearing soft tissue.Although computer-assistive techniques often represent a substantial financial investment, the benefits of using them demonstrate clear advantages to both the clinician and patient. These benefits include: Improved predictability of outcomes, surgeon preparedness, reduction in operating room time, reduction in overall treatment times, improved precision and anatomical accuracy, improved treatment efficiencies, and overall treatment experience, particularly for those patients traveling great distances for access to care.Representative examples will be presented.

Orbital exenteration: an updated review with perspectives

Orbital exenteration is a radical and disfiguring surgery mainly performed in specialized tertiary care centers. Orbital exenteration has long been considered the treatment of choice for managing periocular tumors invading the orbit or primary orbital malignancies. Over the past decades, attention has been directed toward reducing the perioperative morbidity by developing new surgical devices and new strategies and promoting cosmetic rehabilitation by providing adequate facial prostheses. Despite these advances, several studies have questioned the role of orbital exenteration in improving overall survival. The last decade has been marked by the emergence of a new paradigm: the "eye-sparing" strategies based on conservative surgery with or without adjuvant radiotherapy and/or targeted therapies and immunotherapies. We summarize the data on orbital exenteration, including epidemiology, etiologies, use of surgical ablative and reconstructive techniques, complications, outcomes, and the related controversies.

Aplicaciones de la impresión 3D en cirugía plástica reconstructiva

La impresión 3D es una tecnología interesante en constante evolución. También conocida como manufactura aditiva, consiste en la conversión de diseños digitales a modelos físicos mediante la adición de capas sucesivas de material. En años recientes, y tras el vencimiento de múltiples patentes, diversos campos de las ciencias de la salud se han interesado en sus posibles usos, siendo la cirugía plástica una de las especialidades médicas que más ha aprovechado sus ventajas y aplicaciones, en especial la capacidad de crear dispositivos altamente personalizados a costos accesibles. Teniendo en cuenta lo anterior, el objetivo del presente artículo es describir los usos de la impresión 3D en cirugía plástica reconstructiva a partir de una revisión de la literatura.Las principales aplicaciones de la impresión 3D descritas en la literatura incluyen su capacidad para crear modelos anatómicos basados en estudios de imagen de pacientes, que a su vez permiten planificar procedimientos quirúrgicos, fabricar implantes y prótesis personalizadas, crear instrumental quirúrgico para usos específicos y usar biotintas en ingeniería tisular.La impresión 3D es una tecnología prometedora con el potencial de implementar cambios positivos en la práctica de la cirugía plástica reconstructiva en el corto y mediano plazo.

The Accuracy of Digital Face Scans Obtained from 3D Scanners: An In Vitro Study

Face scanners promise wide applications in medicine and dentistry, including facial recognition, capturing facial emotions, facial cosmetic planning and surgery, and maxillofacial rehabilitation. Higher accuracy improves the quality of the data recorded from the face scanner, which ultimately, will improve the outcome. Although there are various face scanners available on the market, there is no evidence of a suitable face scanner for practical applications. The aim of this in vitro study was to analyze the face scans obtained from four scanners; EinScan Pro (EP), EinScan Pro 2X Plus (EP+) (Shining 3D Tech. Co., Ltd. Hangzhou, China), iPhone X (IPX) (Apple Store, Cupertino, CA, USA), and Planmeca ProMax 3D Mid (PM) (Planmeca USA, Inc. IL, USA), and to compare scans obtained from various scanners with the control (measured from Vernier caliper). This should help to identify the appropriate scanner for face scanning. A master face model was created and printed from polylactic acid using the resolution of 200 microns on x, y, and z axes and designed in Rhinoceros 3D modeling software (Rhino, Robert McNeel and Associates for Windows, Washington DC, USA). The face models were 3D scanned with four scanners, five times, according to the manufacturer's recommendations; EinScan Pro (Shining 3D Tech. Co., Ltd. Hangzhou, China), EinScan Pro 2X Plus (Shining 3D Tech. Co., Ltd. Hangzhou, China) using Shining Software, iPhone X (Apple Store, Cupertino, CA, USA) using Bellus3D Face Application (Bellus3D, version 1.6.2, Bellus3D, Inc. Campbell, CA, USA), and Planmeca ProMax 3D Mid (PM) (Planmeca USA, Inc. IL, USA). Scan data files were saved as stereolithography (STL) files for the measurements. From the STL files, digital face models are created in the computer using Rhinoceros 3D modeling software (Rhino, Robert McNeel and Associates for Windows, Washington DC, USA). Various measurements were measured five times from the reference points in three axes (x, y, and z) using a digital Vernier caliper (VC) (Mitutoyo 150 mm Digital Caliper, Mitutoyo Co., Kanagawa, Japan), and the mean was calculated, which was used as the control. Measurements were measured on the digital face models of EP, EP+, IPX, and PM using Rhinoceros 3D modeling software (Rhino, Robert McNeel and Associates for Windows, Washington DC, USA). The descriptive statistics were done from SPSS version 20 (IBM Company, Chicago, USA). One-way ANOVA with post hoc using Scheffe was done to analyze the differences between the control and the scans (EP, EP+, IPX, and PM). The significance level was set at p = 0.05. EP+ showed the highest accuracy. EP showed medium accuracy and some lesser accuracy (accurate until 10 mm of length), but IPX and PM showed the least accuracy. EP+ showed accuracy in measuring the 2 mm of depth (diameter 6 mm). All other scanners (EP, IPX, and PM) showed less accuracy in measuring depth. Finally, the accuracy of an optical scan is dependent on the technology used by each scanner. It is recommended to use EP+ for face scanning.

Radiological Society of North America (RSNA) 3D printing Special Interest Group (SIG): guidelines for medical 3D printing and appropriateness for clinical scenarios

Medical three-dimensional (3D) printing has expanded dramatically over the past three decades with growth in both facility adoption and the variety of medical applications. Consideration for each step required to create accurate 3D printed models from medical imaging data impacts patient care and management. In this paper, a writing group representing the Radiological Society of North America Special Interest Group on 3D Printing (SIG) provides recommendations that have been vetted and voted on by the SIG active membership. This body of work includes appropriate clinical use of anatomic models 3D printed for diagnostic use in the care of patients with specific medical conditions. The recommendations provide guidance for approaches and tools in medical 3D printing, from image acquisition, segmentation of the desired anatomy intended for 3D printing, creation of a 3D-printable model, and post-processing of 3D printed anatomic models for patient care.