Fully digital occlusion planning in orthognathic surgery - A crossover study.

Orthognathic surgery enables patients with severe jaw malocclusions to normalise their chewing function and, as such, to improve their quality of life. Over the last few years, digitalisation has been set in motion by intraoral scanners and the improvement of planning software in the field of oral and maxillofacial surgery. Previous studies based on plaster cast models showed that the virtual occlusion based on digitally scanned models can be comparable to conventional methods. This retrospective crossover study aimed to prove that the virtual occlusion finding with the IPS CaseDesigner® (version 2.3.5.2, KLS Martin, Tuttlingen, Germany) is accurate enough to use intraoral scans exclusively. MATERIALS AND METHODS: A total of 23 orthognathic surgery patients receiving an intraoral scan for their treatment were included in this study. Two experienced maxillofacial surgeons haptically performed the occlusion finding on three-dimensional (3D) stereolithographic models using the fully digital pathway. One surgeon repeated the procedure a second time to evaluate intra-observer variability. The study aimed to show the difference between these two planning methods by upholding the surgical accuracy of less than 2 mm in translation and 2° in rotation. The conventional haptic occlusion was set as a reference throughout the whole study. The data were tested with a one-sample Wilcoxon test for the fit into the surgical accuracy. RESULTS: The difference between the virtual and conventional groups was significantly smaller than the surgical accuracy (all p < 0.001). Both translational movements (anterior/posterior (median 0.51 mm [0.28, 0.88]), left/right (median 0.46 mm [0.20, 0.87]), cranial/caudal (median 0.37 mm [0.11, 0.69])) and rotations (Roll (median 0.71° [0.29, 1.35]), Pitch (median 0.72° [0.29, 1.44]), Yaw (median 1.09° [0.33, 1.60])) were in the range of surgical accuracy (2 mm/2°). The most significant differences were found in the anterior/posterior translation (median 0.51 mm [0.28, 0.88]) and the Yaw rotation (median 1.09° [0.33, 1.60]). CONCLUSION: These results demonstrate that the entirely virtual workflow in orthognathic surgery, including intraoral scanning and the virtual semi-automatic occlusion finding, represents a reliable and state-of-the-art alternative to the conventional haptic method.

Case report: One-stage craniectomy and cranioplasty digital workflow for three-dimensional printed polyetheretherketone implant for an extensive skull multilobular osteochondosarcoma in a dog.

Objective: To report a digital workflow for use and long-term outcome of cranioplasty with a 3D-printed patient-specific Polyetheretherketone (PEEK) implant in a 12-y-old German Shepherd dog after surgical removal of an extensive occipital bone multilobular osteochondrosarcoma (MLO). Study design: Retrospective case report. Animal: A 12-year-old neutered female German Shepherd dog was presented with facial deformity, blindness, tetraparesis, and ataxia. Magnetic resonance imaging (MRI) and computed tomography (CT) identified a large skull-based mass extending extra-and intracranially with severe compression of the cerebellum and occipital lobes of the cerebrum. Methods: One-stage decompressive craniectomy using virtual surgical planned 3D-printed craniotomy cutting guides and the Misonix BoneScalpel® and reconstruction with a patient-specific 3D-printed PEEK cranial implant. Results: 3D-printed craniectomy cutting guides allowed an adequate fit of the cranial implant to the original skull. Misonix BoneScalpel® allowed performing a safe and extensive craniectomy. Postoperative CT (8 weeks after surgery) confirmed the PEEK cranial implant to be in place and without implant rejection. Clinically, the neurological examination identified only a right-hind limb delay in proprioception 8 weeks postoperatively, which remained unchanged at 18 months after surgery. Adjunctive treatment included metronomic chemotherapy. Eighteen months after surgery the dog passed away for reasons unrelated to the MLO, no implant-related complications were reported. Conclusion: 3D-printed craniectomy cutting guides, patient-specific PEEK cranial implant, and metronomic chemotherapy can lead to a successful long-term outcome in dogs with extensive skull MLO. Clinical significance: PEEK is an alternative biomaterial that can be used successfully for skull reconstruction.

Intraosseous myofibroma mimicking an odontogenic lesion: case report, literature review, and differential diagnosis.

BACKGROUND: Intraosseous myofibroma of the jaw is a rare neoplasm of mesenchymal origin with limited comprehensive understanding. It typically affects patients in the first two decades of life with a male predilection. CASE PRESENTATION: This study presents a rare case of myofibroma mimicking an odontogenic lesion in a 2-year-old boy. The patient presented with an incidental finding of a painless swelling of the right mandibular ramus of unknown etiology. Imaging analysis revealed a solid, expansile lesion adjacent to the germinal zone of the right mandibular first molar. Histopathologic analysis and immunohistochemistry after incisional biopsy suggested a possible central odontogenic fibroma, and the patient underwent total enucleation, leading to the final diagnosis of intraosseous myofibroma. Follow-up examinations showed no evidence of recurrence. CONCLUSIONS: This report contributes to the understanding of myofibroma in pediatric patients and underscores the critical role of meticulous histopathologic examination for effective surgical planning and optimal patient outcomes.

Demographics, Utilization, Workflow, and Outcomes Based on Observational Data From the RSNA-ACR 3D Printing Registry.

PURPOSE: The aim of this study was to report data from the first 3 years of operation of the RSNA-ACR 3D Printing Registry. METHODS: Data from June 2020 to June 2023 were extracted, including demographics, indications, workflow, and user assessments. Clinical indications were stratified by 12 organ systems. Imaging modalities, printing technologies, and numbers of parts per case were assessed. Effort data were analyzed, dividing staff members into provider and nonprovider categories. The opinions of clinical users were evaluated using a Likert scale questionnaire, and estimates of procedure time saved were collected. RESULTS: A total of 20 sites and 2,637 cases were included, consisting of 1,863 anatomic models and 774 anatomic guides. Mean patient ages for models and guides were 42.4 ± 24.5 years and 56.3 ± 18.5 years, respectively. Cardiac models were the most common type of model (27.2%), and neurologic guides were the most common type of guide (42.4%). Material jetting, vat photopolymerization, and material extrusion were the most common printing technologies used overall (85.6% of all cases). On average, providers spent 92.4 min and nonproviders spent 335.0 min per case. Providers spent most time on consultation (33.6 min), while nonproviders focused most on segmentation (148.0 min). Confidence in treatment plans increased after using 3-D printing (P < .001). Estimated procedure time savings for 155 cases was 40.5 ± 26.1 min. CONCLUSIONS: Three-dimensional printing is performed at health care facilities for many clinical indications. The registry provides insight into the technologies and workflows used to create anatomic models and guides, and the data show clinical benefits from 3-D printing.

Evaluation of the Dimensional Accuracy of Robot-Guided Laser Osteotomy in Reconstruction with Patient-Specific Implants-An Accuracy Study of Digital High-Tech Procedures.

Background/Objective: With the rapid advancement in surgical technologies, new workflows for mandibular reconstruction are constantly being evaluated. Cutting guides are extensively employed for defining osteotomy planes but are prone to errors during fabrication and positioning. A virtually defined osteotomy plane and drilling holes in robotic surgery minimize potential sources of error and yield highly accurate outcomes. Methods: Ten mandibular replicas were evaluated after cutting-guided saw osteotomy and robot-guided laser osteotomy following reconstruction with patient-specific implants. The descriptive data analysis summarizes the mean, standard deviation (SD), median, minimum, maximum, and root mean square (RMS) values of the surface comparison for 3D printed models regarding trueness and precision. Results: The saw group had a median trueness RMS value of 2.0 mm (SD ± 1.7) and a precision of 1.6 mm (SD ± 1.4). The laser group had a median trueness RMS value of 1.2 mm (SD ± 1.1) and an equal precision of 1.6 mm (SD ± 1.4). These results indicate that robot-guided laser osteotomies have a comparable accuracy to cutting-guided saw osteotomies, even though there was a lack of statistical significance. Conclusions: Despite the limited sample size, this digital high-tech procedure has been shown to be potentially equivalent to the conventional osteotomy method. Robotic surgery and laser osteotomy offers enormous advantages, as they enable the seamless integration of precise virtual preoperative planning and exact execution in the human body, eliminating the need for surgical guides in the future.

An Algorithm for Jaw Pain among Divers.

Background: Temporomandibular disease (TMD) is commonly seen, and divers also experience pain in the temporomandibular joint (TMJ) or masticatory muscles. This article aims to provide a tool for diving physicians or medical professionals involved in diving medicine since jaw pain among divers is a pertinent subject and can be challenging to evaluate without some background in dentistry or maxillofacial surgery. Method: A basic algorithm was developed to provide a tool to differentiate jaw pains experienced by divers. Three brief case studies were developed, and five diving physicians were tasked with diagnosing the cases using the algorithm. Additionally, simple exercises and massage techniques that can benefit patients with TMD, particularly immediately after diving, are outlined. Results: All five diving physicians successfully diagnosed the cases using the algorithm. However, three of them were unable to diagnose the first case (disc luxation) without consulting the algorithm. Nevertheless, all physicians acknowledged the utility of the algorithm. Conclusions: Jaw pain in divers can stem from diverse causes, but effective treatment options exist. Our study findings provide valuable insights to assist diving physicians in making accurate diagnoses and guiding appropriate patient management, which may include referrals to specialists such as dentists, maxillofacial surgeons, or orthodontists.

Simple Electrospinning Method for Biocompatible Polycaprolactone ß-Carotene Scaffolds: Advantages and Limitations.

In this study, electrospun scaffolds were fabricated using polycaprolactone (PCL) loaded with varying concentrations of ß-carotene (1.2%, 2.4%, and 3.6%) via the electrospinning technique. The electrospinning process involved the melting of PCL in acetic acid, followed by the incorporation of ß-carotene powder under constant stirring. Raman spectroscopy revealed a homogeneous distribution of ß-carotene within the PCL matrix. However, the ß-carotene appeared in particulate form, rather than being dissolved and blended with the PCL matrix, a result also confirmed by thermogravimetric analysis. Additionally, X-ray diffraction analysis indicated a decrease in crystallinity with increasing ß-carotene concentration. Mechanical testing of the scaffolds demonstrated an increase in ultimate strain, accompanied by a reduction in ultimate stress, indicating a potential plasticizing effect. Moreover, antimicrobial assays revealed a marginal antibacterial effect against Escherichia coli for scaffolds with higher ß-carotene concentrations. Conversely, preliminary biological assessment using KUSA-A1 mesenchymal cells indicated enhanced cellular proliferation in response to the scaffolds, suggesting the potential biocompatibility and cell-stimulating properties of ß-carotene-loaded PCL scaffolds. Overall, this study provides insights into the fabrication and characterization of electrospun PCL scaffolds containing ß-carotene, laying the groundwork for further exploration in tissue engineering and regenerative medicine applications.

Cleft lip and palate surgery simulator: Open source simulation model.

Objective: Cleft lip and palate is the most common craniofacial birth anomaly and requires surgery in the first year of life. However, craniofacial surgery training opportunities are limited. The aim of this study was to present and evaluate an open-source cleft lip and palate hybrid (casting and three-dimensional (3D) printing) simulation model which can be replicated at low cost to facilitate the teaching and training of cleft surgery anatomy and techniques. Design: The soft tissue component of the cleft surgery training model was casted using a 3D printed 5-component mold and silicone. The bony structure was designed to simulate the facial anatomy and to hold the silicone soft tissue. Setting: Two groups, one group of trainees and one group of expert surgeons, at University Hospital Basel in Switzerland and Pontifical Catholic University of Chile in Santiago, Chile, tested the cleft lip and palate simulation model. Participants completed a Likert-based face and content validity questionnaire to assess the realism of the model and its usefulness in surgical training. Results: More than 70 % of the participants agreed that the model accurately simulated human tissues found in patients with unilateral cleft lip and palate. Over 60 % of the participants also agreed that the model realistically replicated surgical procedures. In addition, 80-90 % of the participants found the model to be a useful and appropriate tool for teaching the anatomy and surgical techniques involved in performing unilateral cleft lip and palate repair. Conclusion: This open-source protocol provides a cost-effective solution for surgeons to introduce the cleft morphology and surgical techniques to trainees on a regular basis. It addresses the current financial barrier that limits access to commercially available models during the early stages of surgeon training prior to specialization in the field.

Patient-specific implants made of 3D printed bioresorbable polymers at the point-of-care: material, technology, and scope of surgical application.

BACKGROUND: Bioresorbable patient-specific additive-manufactured bone grafts, meshes, and plates are emerging as a promising alternative that can overcome the challenges associated with conventional off-the-shelf implants. The fabrication of patient-specific implants (PSIs) directly at the point-of-care (POC), such as hospitals, clinics, and surgical centers, allows for more flexible, faster, and more efficient processes, reducing the need for outsourcing to external manufacturers. We want to emphasize the potential advantages of producing bioresorbable polymer implants for cranio-maxillofacial surgery at the POC by highlighting its surgical applications, benefits, and limitations. METHODS: This study describes the workflow of designing and fabricating degradable polymeric PSIs using three-dimensional (3D) printing technology. The cortical bone was segmented from the patient's computed tomography data using Materialise Mimics software, and the PSIs were designed created using Geomagic Freeform and nTopology software. The implants were finally printed via Arburg Plastic Freeforming (APF) of medical-grade poly (L-lactide-co-D, L-lactide) with 30% ß-tricalcium phosphate and evaluated for fit. RESULTS: 3D printed implants using APF technology showed surfaces with highly uniform and well-connected droplets with minimal gap formation between the printed paths. For the plates and meshes, a wall thickness down to 0.8 mm could be achieved. In this study, we successfully printed plates for osteosynthesis, implants for orbital floor fractures, meshes for alveolar bone regeneration, and bone scaffolds with interconnected channels. CONCLUSIONS: This study shows the feasibility of using 3D printing to create degradable polymeric PSIs seamlessly integrated into virtual surgical planning workflows. Implementing POC 3D printing of biodegradable PSI can potentially improve therapeutic outcomes, but regulatory compliance must be addressed.

Virtual Surgical Planning and Customized CAD/CAM Cranial Implants: Preoperative and Intraoperative Strategies for Temporal Intraosseous Meningioma Resection.

Primary intraosseous meningioma (PIM) is a rare subtype of extradural meningiomas, with the indication for surgical resection in most cases. With an increasing demand for efficient workflows with optimal functional and cosmetical results, techniques for bone reconstruction after resection are developing rapidly. The authors present 2 cases with one-stage cranioplasty after resection of PIM, using 3D technology for preplanned patient-specific implants. In the first case, a premanufactured patient-specific PEEK implant was used for reconstruction; in the second case, a 3-dimensional (3D)-based premanufactured silicon mold was used to produce a customized PMMA implant intraoperatively. Both techniques enabled the surgeons to achieve optimal intraoperative fit of the implant after craniectomy, leading to satisfying functional and cosmetic results. The use of 3D technology, such as Computer-Aided Design and Computer-Aided Manufacturing (CAD/CAM) for the production of patient-specific implants can optimize 1-stage cranioplasty after PIM resection.

A balance of biocompatibility and antibacterial capability of 3D printed PEEK implants with natural totarol coating.

OBJECTIVE: Polyetheretherketone (PEEK), a biomaterial with appropriate bone-like mechanical properties and excellent biocompatibility, is widely applied in cranio-maxillofacial and dental applications. However, the lack of antibacterial effect is an essential drawback of PEEK material and might lead to infection and osseointegration issues. This study aims to apply a natural antibacterial agent, totarol coating onto the 3D printed PEEK surface and find an optimized concentration with balanced cytocompatibility, osteogenesis, and antibacterial capability. METHODS: In this study, a natural antibacterial agent, totarol, was applied as a coating to fused filament fabrication (FFF) 3D printed PEEK surfaces at a series of increasing concentrations (1 mg/ml, 5 mg/ml, 10 mg/ml, 15 mg/ml, and 20 mg/ml). The samples were then evaluated for cytocompatibility with L929 fibroblast and SAOS-2 osteoblast using live/dead staining and CCK-8 assay. The antibacterial capability was assessed by crystal violet staining, live/dead staining, and scanning electron microscopy (SEM) utilizing the oral primary colonizer S. gordonii and isolates of mixed oral bacteria in a stirring system simulating the oral environment. The appropriate safe working concentration for totarol coating is selected based on the results of the cytocompatibility and antibacterial test. Subsequently, the influence on osteogenic differentiation was evaluated by alkaline phosphatase (ALP) and alizarin red staining (ARS) analysis of pre-osteoblasts. RESULTS: Our results showed that the optimal concentration of totarol solution for promising antibacterial coating was approximately 10 mg/ml. Such surfaces could play an excellent antibacterial role by inducing a contact-killing effect with an inhibitory effect against biofilm development without affecting the healing of soft and hard tissues around FFF 3D printed PEEK implants or abutments. SIGNIFICANCE: This study indicates that the totarol coated PEEK has an improved antibacterial effect with excellent biocompatibility providing great clinical potential as an orthopedic/dental implant/abutment material.

Insights into Orbital Symmetry: A Comprehensive Retrospective Study of 372 Computed Tomography Scans.

Background: The operation planning and production of individualized implants with the help of AI-based software after orbital fractures have become increasingly important in recent years. This retrospective study aimed to investigate the healthy orbitae of 372 patients from CT images in the bone and soft tissue windows using the Disior™ Bonelogic™ CMF Orbital software. (version 2.1.28). Methods: We analyzed the variables orbital volume, length, and area as a function of age and gender and compared bone and soft tissue windows. Results: For all variables, the intraclass correlation showed excellent agreement between the bone and soft tissue windows (p < 0.001). All variables showed higher values when calculated based on bone fenestration with, on average, 1 mL more volume, 0.35 mm more length, and 0.71 cm2 more area (p < 0.001). Across all age groups, men displayed higher values than women with, on average, 8.1 mL larger volume, a 4.78 mm longer orbit, and an 8.5 cm2 larger orbital area (p < 0.001). There was also a non-significant trend in all variables and both sexes toward growth with increasing age. Conclusions: These results mean that, due to the symmetry of the orbits in both the bone and soft tissue windows, the healthy orbit can be mirrored for surgical planning in the event of a fracture.

Aortic root rotation: morphological analysis of the aortic root with three-dimensional computed tomography.

OBJECTIVES: The aortic root (AoR) rotation and its spatial morphology at the base of the heart were postulated but not described in every detail. AoR rotation modalities may play an important role in decision-making during AoR surgery and its outcome. The aim was to provide a detailed spatial anatomy of the AoR rotation and its relation to the vital surrounding structure. METHODS: The AoR rotation and its relation to the surrounding structure were assessed in 104 patients with tricuspid aortic valve. The interatrial septum was chosen as a reference to describe AoR rotation that marked the midline of the heart base as a landmark for the AoR rotation direction. Intermediate, clockwise and counterclockwise AoR rotations were defined based on the mentioned reference structures. RESULTS: The AoR rotation was successfully assessed in 104 patients undergoing ascending aorta and or AoR intervention by multidetector row computed tomography. AoR was positioned normally in 53.8% of cases (n = 56) and rotated counterclockwise in 5.8% (n = 6) and clockwise in 40.4% (n = 42) of cases. In clockwise AoR rotation, the right coronary sinus was positioned in proximity to the right atrium and of the tricuspid valve, whereas in a counterclockwise rotation, the noncoronary sinus was placed over the tricuspid valve just over the membranous septum. CONCLUSIONS: The AoR's rotation can be diagnosed using multidetector row computed tomography. Understanding the anatomy of the aortic valve related to rotational position helps guide surgical decision-making in performing AoR reconstruction.

In-house 3D-printed custom splints for non-operative treatment of distal radial fractures: a randomized controlled trial.

We compared patient satisfaction and clinical effectiveness of 3D-printed splints made of photopolymer resin to conventional fibre glass casts in treating distal radial fractures. A total of 39 patients with minimally displaced distal radius fractures were included and randomized. Of them, 20 were immobilized in a fibre glass cast and 19 in a 3D-printed forearm splint. The 3D-printed splints were custom-designed based on forearm surface scanning with a handheld device and printed in-house using digital light processing printing technology. Patient satisfaction and clinical effectiveness were assessed with questionnaires 1 and 6 weeks after the initiation of immobilization. Fracture healing, pain, range of motion, grip strength and the DASH and PRWE scores were assessed up to 1-year follow-up. 3D-printed splints proved to be equally well tolerated by the patients and equally clinically effective as conventional fibre glass casts although there was a higher rate of minor complications. 3D-printed splints present a safe alternative, especially in young, active patients, for non-operative treatment of distal radial fractures.Level of evidence: I.

Three-Dimensional Printable Open-Source Cleft Lip and Palate Impression Trays: A Single-Impression Workflow.

SUMMARY: Documenting complex three-dimensional (3D) cleft lip and palate malformation with plaster casts based on maxillary impressions is standard care. Presurgical orthopedic treatment also requires an impression. Digital impression-taking in patients with cleft lip and palate is feasible, but procurement costs hinder clinical implementation. Individualized impression trays allow for a precise impression, limiting airway risk. The authors present an open-source impression tray library with scalable impression trays not requiring 3D modeling knowledge. The cleft lip and palate impression tray library is accessible on Open Science Framework. Different shapes are available, and the tray size is selected based on the tuber distance. This allows 3D printing with biocompatible material at the point of care complying with local regulations. The open-source cleft tray library presented offers a hybrid solution for cleft centers, pending the implementation of digital impression.

Precision Surgery for Orbital Cavernous Hemangiomas: The Role of Three-Dimensional Printing in Individualized Resection-An Educational Experience.

Orbital cavernous hemangiomas are the most common primary orbital tumors in adults, providing challenges for optimal surgical approach planning within an anatomically complex area with close proximity to vital neurovascular structures. The authors present an individualized lateral mini-orbitozygomatic approach for the resection of an orbital cavernous haemangioma based on a preoperative 3-dimensional-printed model. This individualized approach enabled the surgeons to achieve optimal exposure while maintaining safety during the resection of the lesion, but also to respect the patient's physiognomy and hairline. In addition, the model was used for patient informed consent, helping the patient understand the procedure. Although adding additional effort to preoperative planning, 3-dimensional model-based approaches can offer great benefits when it comes to customizing surgical approaches, especially for anatomically challenging resections.

Conservative endoscopic closure with fibrin glue of an aorto-esophageal fistula secondary to endovascular repair of a contained penetrating atherosclerotic ulcer rupture.

An aorto-esophageal fistula (AEF) is a rare complication of aortic surgery but can cause potentially lethal upper gastrointestinal tract bleeding. A patient presented with an AEF secondary to emergency endovascular repair of a contained penetrating atherosclerotic ulcer rupture of the thoracic aorta and was successfully treated with endoscopic closure using fibrin glue. As endovascular repair becomes increasingly common, a greater incidence of AEFs should be anticipated and the treatment options better described.