Craniomaxillofacial (CMF) and nasal landmark detection are fundamental components in computer-assisted surgery. Medical landmark detection method includes regression-based and heatmap-based methods, and heatmap-based methods are among the main methodology branches. The method relies on high-resolution (HR) features containing more location information to reduce the network error caused by sub-pixel location. Previous studies extracted HR patches around each landmark from downsampling images via object detection and subsequently input them into the network to obtain HR features. Complex multistage tasks affect accuracy. The network error caused by downsampling and upsampling operations during training, which interpolates low-resolution features to generate HR features or predicted heatmap, is still significant. We propose standard super-resolution landmark detection networks (SRLD-Net) and super-resolution UNet (SR-UNet) to reduce network error effectively. SRLD-Net used Pyramid pooling block, Pyramid fusion block and super-resolution fusion block to combine global prior knowledge and multi-scale local features, similarly, SR-UNet adopts Pyramid pooling block and super-resolution block. They can obviously improve representation learning ability of our proposed methods. Then the super-resolution upsampling layer is utilized to generate detail predicted heatmap. Our proposed networks were compared to state-of-the-art methods using the craniomaxillofacial, nasal, and mandibular molar datasets, demonstrating better performance. The mean errors of 18 CMF, 6 nasal and 14 mandibular landmarks are 1.39 ± 1.04, 1.31 ± 1.09, 2.01 ± 4.33 mm. These results indicate that the super-resolution methods have great potential in medical landmark detection tasks. This paper provides two effective heatmap-based landmark detection networks and the code is released in https://github.com/Runshi-Zhang/SRLD-Net.

In mandibular reconstruction, computer-assisted procedures, including virtual surgical planning (VSP) and additive manufacturing (AM), have become an integral part of routine clinical practice. Especially complex cases with extensive defects after ablative tumor surgery benefit from a computer-assisted approach. Various CAD/CAM-manufactured tools such as surgical guides (guides for osteotomy, resection and predrilling) support the transition from virtual planning to surgery. Patient-specific implants (PSIs) are of particular value as they facilitate both osteosynthesis and the positioning of bone elements. Computer-based approaches may be associated with higher accuracy, efficiency, and superior patient outcomes. However, certain limitations should be considered, such as additional costs or restricted availability. In the future, automation of the planning process and augmented reality techniques, as well as MRI as a non-ionizing imaging modality, have the potential to further improve the digital workflow.

The field of craniomaxillofacial (CMF) surgery is rich in pathological diversity and broad in the ages that it treats. Moreover, the CMF skeleton is a complex confluence of sensory organs and hard and soft tissue with load-bearing demands that can change within millimeters. Computer-aided design (CAD) and additive manufacturing (AM) create extraordinary opportunities to repair the infinite array of craniomaxillofacial defects that exist because of the aforementioned circumstances. 3D printed scaffolds have the potential to serve as a comparable if not superior alternative to the \"gold standard\" autologous graft. In vitro and in vivo studies continue to investigate the optimal 3D printed scaffold design and composition to foster bone regeneration that is suited to the unique biological and mechanical environment of each CMF defect. Furthermore, 3D printed fixation devices serve as a patient-specific alternative to those that are available off-the-shelf with an opportunity to reduce operative time and optimize fit. Similar benefits have been found to apply to 3D printed anatomical models and surgical guides for preoperative or intraoperative use. Creation and implementation of these devices requires extensive preclinical and clinical research, novel manufacturing capabilities, and strict regulatory oversight. Researchers, manufacturers, CMF surgeons, and the United States Food and Drug Administration (FDA) are working in tandem to further the development of such technology within their respective domains, all with a mutual goal to deliver safe, effective, cost-efficient, and patient-specific CMF care. This manuscript reviews FDA regulatory status, 3D printing techniques, biomaterials, and sterilization procedures suitable for 3D printed devices of the craniomaxillofacial skeleton. It also seeks to discuss recent clinical applications, economic feasibility, and future directions of this novel technology. By reviewing the current state of 3D printing in CMF surgery, we hope to gain a better understanding of its impact and in turn identify opportunities to further the development of patient-specific surgical care.

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The case report describes the use of ultrasound-activated resorbable implants for surgical repair of comminuted cranial fractures in a 10 years old medium sized mix-breed dog being injured from a horse kick.
Der Fallbericht beschreibt die Verwendung von ultraschallaktivierten resorbierbaren Implantaten zur chirurgischen Reparatur einer Schädeltrümmerfrakturen bei einem 10 Jahre alten mittelgrossen Mischlingshund, der durch einen Pferdetritt verletzt wurde.
Ce rapport de cas décrit l’utilisation d’implants résorbables activés par ultrasons pour la réparation chirurgicale de fractures crâniennes comminutives chez un chien de race moyenne âgé de 10 ans, blessé par un coup de pied de cheval.
Il rapporto di questo caso descrive l’uso di impianti riassorbibili attivati ​​da ultrasuoni per la riparazione chirurgica di fratture craniche comminute in un cane di taglia media e di razza mista di 10 anni ferito da un calcio di cavallo.

Three-dimensional (3D) imaging technologies are increasingly used in craniomaxillofacial (CMF) surgery, especially to enable clinicians to get an effective approach and obtain better treatment results during different preoperative and postoperative phases, namely during image acquisition and diagnosis, virtual surgical planning (VSP), actual surgery, and treatment outcome assessment. The article presents an overview of 3D imaging technologies used in the aforementioned phases of the most common CMF surgery. We searched for relevant studies on 3D imaging applications in CMF surgery published over the past 10 years in the PubMed, ProQuest (Medline), Web of Science, Science Direct, Clinical Key, and Embase databases. A total of 2094 articles were found, of which 712 were relevant. An additional 26 manually searched articles were included in the analysis. The findings of the review demonstrated that 3D imaging technology is becoming increasingly popular in clinical practice and an essential tool for plastic surgeons. This review provides information that will help researchers and clinicians consider the use of 3D imaging techniques in CMF surgery to improve the quality of surgical procedures and achieve satisfactory treatment outcomes.

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Titanium and stainless steel are commonly known as osteosynthesis materials with high strength and good biocompatibility. However, they have the big disadvantage that a second operation for hardware removal is necessary. Although resorbable systems made of polymers or magnesium are increasingly used, they show some severe adverse foreign body reactions or unsatisfying degradation behavior. Therefore, we started to investigate molybdenum as a potential new biodegradable material for osteosynthesis in craniomaxillofacial surgery. To characterize molybdenum as a biocompatible material, we performed in vitro assays in accordance with ISO Norm 10993-5. In four different experimental setups, we showed that pure molybdenum and molybdenum rhenium alloys do not lead to cytotoxicity in human and mouse fibroblasts. We also examined the degradation behavior of molybdenum by carrying out long-term immersion tests (up to 6 months) with molybdenum sheet metal. We showed that molybdenum has sufficient mechanical stability over at least 6 months for implants on the one hand and is subject to very uniform degradation on the other. The results of our experiments are very promising for the development of new resorbable osteosynthesis materials for craniomaxillofacial surgery based on molybdenum.

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.

Advances in computer-aided design and computer-aided manufacturing software have improved translational applications of virtual surgical planning (VSP) in craniomaxillofacial surgery, allowing for precise and accurate fabrication of cutting guides, stereolithographic models, and custom implants. High-resolution computed tomography (CT) imaging has traditionally been the gold standard imaging modality for VSP in craniomaxillofacial surgery but delivers ionizing radiation. Black bone magnetic resonance imaging (MRI) reduces the risks related to radiation exposure and has comparable functionality when compared with CT for VSP. Our group has studied the accuracy of utilizing black bone MRI in planning and executing several types of craniofacial surgeries, including cranial vault remodeling, maxillary advancement, and mandibular reconstruction using fibular bone. Here, we review clinical applications of black bone MRI pertaining to VSP and three-dimensional (3D)-printed guide creation for craniomaxillofacial surgery. Herein, we review the existing literature and our institutional experience comparing black bone MRI and CT in VSP-generated 3D model creation in cadaveric craniofacial surgeries including cranial vault reconstruction, maxillary advancement, and mandibular reconstruction with fibular free flap. Cadaver studies have demonstrated the ability to perform VSP and execute the procedure based on black bone MRI data and achieve outcomes similar to CT when performed for cranial vault reshaping, maxillary advancement, and mandibular reconstruction with free fibula. Limitations of the technology include increased time and costs of the MRI compared with CT and the possible need for general anesthesia or sedation in the pediatric population. VSP and 3D surgical guide creation can be performed using black bone MRI with comparable accuracy to high-resolution CT scans in a wide variety of craniofacial reconstructions. Successful segmentation, VSP, and 3D printing of accurate guides from black bone MRI demonstrate potential to change the preoperative planning standard of care. Black bone MRI also reduces exposure to ionizing radiation, which is of particular concern for the pediatric population or patients undergoing multiple scans.