No funding was received for this work.

1. Repositioning of the jaws
NOTE: This section is performed using the imaging software (i.e., Dolphin).
<ol>
	<li>Load the facial bones CT image DICOM files of the patient (Figure 1A) into the software by selecting the 3D button on the left and clicking Import New DICOM (Supplemental Figure 1). Enter the 3D editing mode by clicking 3D | Edit.</li>
	<li>Orient the 3D image using the orientation button on the left. Create a panoramic image using the build X-rays button on the left (Supplemental Figure 2).</li>
	<li>Go to Tools | Orthognathic Surgical Planning | Start New Workup.</li>
	<li>Position the segments in the panoramic image. Crop each segment to contain the area of the corresponding bone. 
	NOTE: The cleaning stage is useful when, for accuracy, a scanned dental arch and a CT scan are superimposed to create a wafer. This is not indicated in a &#8220;waferless&#8221; surgery as presented here and thus at this stage one can clean CT imperfections if they exist.</li>
	<li>Choose the appropriate osteotomy for the patient on the left pan under osteotomies (such as LeFort I, sagittal split, etc.). Mark the exact location of the osteotomy lines by moving the yellow circles (Supplemental Figure 3). 
	NOTE: It is extremely important to note the root apexes of the teeth as the location of the osteotomy decided here will be the one performed later based on the surgical guides. Always avoid the roots and maintain a 5 mm distance.</li>
	<li>Mark different landmarks by left clicking on the right location for each suggested landmark. 
	NOTE: This is important for measurements and movement purposes in the next stages.</li>
	<li>Perform movements of bone segments. Drag the bone to the right location, or for accuracy, right click and choose Input Movements Using Keyboard.</li>
	<li>In order to track the movement of key landmarks, press Treat Options Button on the left and choose Show Landmark Offset and Measurement Tables. 
	NOTE: In the next tab the pre and post virtually planned operation can be observed (Supplemental Figure 4).</li>
	<li>Export the stl files of the two different positions of bone segments, one in the pre-operative stage and one in the post-operative stage, using the slide bar on the left and the Export Segments in stl button on the left.</li>
</ol>
2. Preparation of patient-specific fixation plates and surgical guides
NOTE: This section is performed using the 3D design software (i.e., Geomagic Freeform).
<ol>
	<li>Click File | Import Model (Supplemental Figure 5A) to import the stl files obtained from step 1.9 showing the position of the upper jaw and midface following the osteotomy but prior to the repositioning in the final position.</li>
	<li>Start with planning the patient-specific fixation plates in the final position of the upper jaw. In the tool palette on the left under the Planes category, select Create Plane (Supplemental Figure 6A). Here the initial design of the plates will be performed. Manually move the plane parallel to the bone where the plate will be placed.</li>
	<li>Under the Sketch category (Supplemental Figure 6B), choose a circle shape and create circles with a size appropriate for the screws to be used later. Create a second circle around the previous one 3 mm larger in diameter to outline the fixation plate. 
	NOTE: The size of the circles is determined based on the fixation sets used in each institute. The circles are placed above and below the planned surgical osteotomy (decided already in section 1).</li>
	<li>Project the design from the plane to the bone. Under the Curves category (Supplemental Figure 7), use the project sketch tool and choose the circles that will be transferred from the plane to the bone.</li>
	<li>To connect the outer circles for the outer border plate design, choose under the Curves category the split tool and define the part of the circle that will be removed to allow for a connection to the adjacent circles. Using the select option, choose the defined part of the circle and delete it. Under the Curves category, use the draw curve tool and connect the outer circles to create a continuous outer shape of the patient-specific plate.</li>
	<li>Before creating the fixation plate, duplicate the upper jaw by right clicking and selecting Duplicate from the object list (Supplemental Figure 7A). This will allow the use of the Boolean tool in the next stages to create the fixation plate.</li>
	<li>Under the Detail Clay category, use the emboss with curve tool. This creates the volume of the fixation plate based on the curves previously projected. Choose the outer shape curve and then place the circle-shaped cursor inside and on the surface of the shaped plate (note that the cursor should be placed on the side to be embossed). At the bottom, choose the parameters of the function, mainly the Distance option that controls the thickness of the future fixation plate.</li>
	<li>Separate the plate from the upper jaw. At this stage the Boolean option is performed. Choose the original upper jaw, right click from the object list and click Boolean | Remove from | Upper Jaw with Plate.</li>
	<li>To create the holes for the screws, either draw the screws/scan them and then use the Boolean option or use the SubD tool. Under the SubD Surfaces category (Supplemental Figure 8), use the wire cut SubD tool to create rods perpendicular to the plate in the size of desired holes, which is performed based on the circles created in step 2.3 originating from the perpendicular plane.</li>
	<li>Next, subtract the rods from the plate using the Boolean | Remove from technique. 
	NOTE: At this stage the final fixation plate is ready (Supplemental Figure 9). Appropriate surgical guides need to be planned for the osteotomy in order for the plates to fit perfectly.</li>
	<li>To create the guides, reposition the upper jaw to its original location but with the screw holes marked in the bone according to the fixation plate created in the final position of the jaw (note the holes in the midface do not change position as the midface stays in the same position).
	<ol>
		<li>To perform this, reposition the jaw with the curves for the holes used for the final fixation plate to the original location of the jaw prior to the movement. Under the Select/Move Clay category, use the Register Pieces option. choose the Source (upper jaw post movement) and the Target (upper jaw and midface prior to the movement). Use a large number of fixed points on both objects for accuracy in the repositioning.</li>
	</ol>
	</li>
	<li>Based on newly positioned holes create the surgical guides in a similar way as described for the fixation plates (steps 2.3&#8722;2.10).</li>
</ol>

<ol>
	<li>Hull, C. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Apparatus for production of three-dmensonal objects by stereo thography. , (1986).</li><li>Shilo, D., Emodi, O., Blanc, O., Noy, D., Rachmiel, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Printing+the+Future-Updates+in+3D+Printing+for+Surgical+Applications.">Printing the Future-Updates in 3D Printing for Surgical Applications.</a> Rambam Maimonides Medical Journal. 9 (3), 20 (2018).</li><li>Emodi, O., Shilo, D., Israel, Y., Rachmiel, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+planning+and+printing+of+guides+and+templates+for+reconstruction+of+the+mandibular+ramus+and+condyle+using+autogenous+costochondral+grafts.">Three-dimensional planning and printing of guides and templates for reconstruction of the mandibular ramus and condyle using autogenous costochondral grafts.</a> British Journal of Oral and Maxillofacial Surgery. 55 (1), 102-104 (2017).</li><li>Leiser, Y., Shilo, D., Wolff, A., Rachmiel, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+reconstruction+in+mandibular+avulsion+injuries.">Functional reconstruction in mandibular avulsion injuries.</a> Journal of Craniofacial Surgery. 27 (8), 2113-2116 (2016).</li><li>Rachmiel, A., Shilo, D., Blanc, O., Emodi, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reconstruction+of+complex+mandibular+defects+using+integrated+dental+custom-made+titanium+implants.">Reconstruction of complex mandibular defects using integrated dental custom-made titanium implants.</a> British Journal of Oral and Maxillofacial Surgery. 55 (4), 425-427 (2017).</li><li>Lauren, M., McIntyre, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+computer-assisted+method+for+design+and+fabrication+of+occlusal+splints.">A new computer-assisted method for design and fabrication of occlusal splints.</a> American Journal of Orthodontics and Dentofacial Orthopedics. 133 (4), 130-135 (2008).</li><li>Song, K. -. G., Baek, S. -. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+the+accuracy+of+the+three-dimensional+virtual+method+and+the+conventional+manual+method+for+model+surgery+and+intermediate+wafer+fabrication.">Comparison of the accuracy of the three-dimensional virtual method and the conventional manual method for model surgery and intermediate wafer fabrication.</a> Oral Surgery, Oral Medicine, Oral Pathology, and Oral Radiology. 107 (1), 13-21 (2009).</li><li>Mazzoni, S., Bianchi, A., Schiariti, G., Badiali, G., Marchetti, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Computer-aided+design+and+computer-aided+manufacturing+cutting+guides+and+customized+titanium+plates+are+useful+in+upper+maxilla+waferless+repositioning.">Computer-aided design and computer-aided manufacturing cutting guides and customized titanium plates are useful in upper maxilla waferless repositioning.</a> Journal of Oral and Maxillofacial Surgery. 73 (4), 701-707 (2015).</li><li>Hanafy, M., Akoush, Y., Abou-ElFetouh, A., Mounir, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Precision+of+orthognathic+digital+plan+transfer+using+patient-specific+cutting+guides+and+osteosynthesis+versus+mixed+analogue-digitally+planned+surgery:+a+randomized+controlled+clinical+trial.">Precision of orthognathic digital plan transfer using patient-specific cutting guides and osteosynthesis versus mixed analogue-digitally planned surgery: a randomized controlled clinical trial.</a> International Journal of Oral and Maxillofacial Surgery. 49 (1), 62-68 (2019).</li><li>Tack, P., Victor, J., Gemmel, P., Annemans, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=3D-printing+techniques+in+a+medical+setting:+a+systematic+literature+review.">3D-printing techniques in a medical setting: a systematic literature review.</a> Biomedical Engineering Online. 15 (1), 115 (2016).</li></ol>

The authors have nothing to disclose.

3D planning and printing is one of the most rapidly evolving methods in the surgical field. It is not only a promising tool for the future, but a practical tool used nowadays for highly accurate surgical results and patient-specific solutions. It allows for highly accurate results and reduces the dependency on the surgeon&#8217;s experience10. It solves many of the disadvantages of previous old fashion surgical methods, but the costs delay the full implementation of the method10<...

3D printing is an additive method based on gradual placement of layers from different materials, thus creating 3D objects. It was originally developed for rapid prototyping and was introduced in 1984 by Charles Hull, who is considered the inventor of the stereolithography method based on solidifying layers of photopolymer resin1. Technological advancements in virtual planning of surgeries and planning and printing of patient-specific implants are constantly evolving. Innovations arise both in the field of computer assisted design (CAD) software and in 3D printing technologies2. Simultaneous to developments in technology, the software and printers become more user-friendly. This shortens the time required for planning and printing and allows the surgeon the option to plan his/her operations and create his/her own patient-specific surgical guides and fixation plates in a field that was exclusively an engineer&#8217;s &#8220;playground&#8221;. These developments also allow for surgeons and engineers to introduce new applications and designs of patient-specific implants3,4,5.
One of these applications is 3D planning of orthognathic surgeries followed by 3D planning and printing of surgical guides and patient-specific fixation plates. Historically, orthognathic surgeries were planned using articulators. A facebow was used to register the relationship of the upper jaw to the temporomandibular joint thus positioning the patient&#8217;s casts in the articulator. Later, the surgical movements were performed on the casts and an acrylic wafer was prepared to help with proper positioning of the jaws during surgery. This method was used for many years and is still used nowadays by most, but the utilization of cone beam computed tomography (CT) together with intra-oral scanners and CAD software allowed for accurate planning, sparing the need for facebows or casts and moving towards creation of digitally planned wafers6. This method reduced the inaccuracy of manual manipulation and measurements but still had flaws including using the instable lower jaw as a reference point for positioning the upper jaw and lack of control over the vertical positioning of the upper jaw7. Thus, a new method was introduced. This method is called the &#8220;waferless&#8221; surgery and is based on repositioning of the jaws anatomically using surgical cutting guides and patient-specific fixation titanium plates8. This method resolves the disadvantages of the digital wafer method described before. We will describe this method, which allows the surgeon complete freedom in planning these surgeries in a patient-specific manner, with minimal possible errors and inaccuracies. This method allows for a &#8220;waferless&#8221; surgery, which means there is no need for using the opposed jaw as reference for repositioning the bones, thus decreasing the inaccuracies derived from this reliance9.

<table><tbody><tr><td>Dolphin imaging software</td><td>Dolphin Imaging Systems LLC (Patterson Dental Supply, Inc)</td><td></td><td>3D analysis and virtual planning of orthognathic surgeries</td></tr><tr><td>Geomagic Freeform</td><td>3D systems</td><td></td><td>Sculpted Engineering Design</td></tr></tbody></table>

treatment of facial deformities using 3d planning and printing of patient-specific implants

Technological advancements in surgical planning and patient-specific implants are constantly evolving. One can either adopt the technology to achieve better results, even in the less experienced hand, or continue without it. As technology develops and becomes more user-friendly, we believe it is time to allow the surgeon the option to plan his/her operations and create his/her own patient-specific surgical guides and fixation plates allowing him full control over the process. We present here a protocol for 3D planning of the operation followed by 3D planning and printing of surgical guides and patient-specific fixation implants. During this process we use two commercial computer-assisted design (CAD) software. We also use a fused deposition&#160;modeling printer for the surgical guides and a selective laser sintering printer for the titanium patient-specific fixation implants. The process includes computed tomography (CT) imaging acquisition, 3D segmentation of the skull and facial bones from the CT, 3D planning of the operations, 3D planning of patient-specific fixation implant according to the final position of the bones, 3D planning of surgical guides for performing an accurate osteotomy and preparing the bone for the fixation plates, and 3D printing of the surgical guides and the patient-specific fixation plates. The advantages of the method include full control over the surgery, planned osteotomies and fixation plates, significant reduction in price, reduction in operation duration, superior performance and highly accurate results. Limitations include the need to master the CAD programs.

To observe the clinical use of the method, we present a case of a 23 year old female. She suffered from condylar hyperplasia at a younger age in the right condyle resulting in asymmetry of both jaws. Figure 1A shows the retrognathic upper jaw and prognathic lower jaw exhibiting the discrepancies between the jaws. In the frontal view, the severe asymmetry can be observed as detailed using the yellow and red lines. Using the imaging software (Supplemental Figure 1), a surgical...

Watch this Scientific Journal Video about Treatment of Facial Deformities using 3D Planning and Printing of Patient-Specific Implants at JoVE.com

Treatment of Facial Deformities using 3D Planning and Printing of Patient-Specific Implants

As technology develops and becomes more user-friendly, planning of operations and patient-specific surgical guides and fixation plates should be performed by the surgeon. We present a protocol for 3D planning of orthognathic skeletal movements and 3D planning and printing of patient-specific fixation plates and surgical guides.

Technological advancements in surgical planning and patient-specific implants are constantly evolving. One can either adopt the technology to achieve ...

treatment-facial-deformities-using-3d-planning-printing-patient

Universidad de Cartagena UDEC

Research

JoVE Journal

Medicine

7.2K Views.  Rambam Medical Care Center. As technology develops and becomes more user-friendly, planning of operations and patient-specific surgical guides and fixation plates should be performed by the surgeon. We present a protocol for 3D planning of orthognathic skeletal movements and 3D planning and printing of patient-specific fixation plates and surgical guides.

Video: Treatment of Facial Deformities using 3D Planning and Printing of Patient-Specific Implants

Voxel Printing Anatomy: Design and Fabrication of Realistic, Presurgical Planning Models through Bitmap Printing

Most applications of 3-dimensional (3D) printing for presurgical planning have been limited to bony structures and simple morphological descriptions of complex organs due to the fundamental limitations in accuracy, quality, and efficiency of the current modeling paradigm. This has largely ignored the soft tissue critical to most surgical specialties where the interior of an object matters and anatomical boundaries transition gradually. Therefore, the needs of the biomedical industry to replicate human tissue, which displays multiple scales of organization and varying material distributions, necessitate new forms of representation. 
Presented here is a novel technique to create 3D models directly from medical images, which are superior in spatial and contrast resolution to current 3D modeling methods and contain previously unachievable spatial fidelity and soft tissue differentiation. Also presented are empirical measurements of novel, additively manufactured composites that span the gamut of material stiffnesses seen in soft biological tissues from MRI and CT. These unique volumetric design and printing methods allow for deterministic and continuous adjustment of material stiffness and color. This capability enables an entirely new application of additive manufacturing to presurgical planning: mechanical realism. As a natural complement to existing models that provide appearance matching, these new models also allow medical professionals to "feel" the spatially varying material properties of a tissue simulant-a critical addition to a field in which tactile sensation plays a key role.

This method demonstrates a voxel-based 3D printing workflow, which prints directly from medical images with exact spatial fidelity and spatial/contrast resolution. This enables the precise, graduated control of material distributions through morphologically complex, graduated materials correlated to radiodensity without loss or alteration of data.

Most applications of 3-dimensional (3D) printing for presurgical planning have been limited to bony structures and simple morphological descriptions of ...

Bioengineering

Designing CAD/CAM Surgical Guides for Maxillary Reconstruction Using an In-house Approach

Computer-aided design/computer-assisted manufacturing (CAD/CAM) is now being evaluated as a preparative technique for maxillofacial surgery. Because this technique is expensive and available in only limited areas of the world, we developed a novel CAD/CAM surgical guide using an in-house approach. By using the CAD software, the maxillary resection area and cutting planes and the fibular cutting planes and angles are determined. Once the resection area is decided, the necessary faces are extracted using a Boolean modifier. These superficial faces are united to fit the surface of the bones and thickened to stabilize the solids. Not only the cutting guides for the fibula and maxilla but also the location arrangement of the transferred bone segments is defined by thickening the superficial faces. The CAD design is recorded as .stl files and three-dimensionally (3-D) printed as actual surgical guides. To check the accuracy of the guides, model surgery using 3-D-printed facial and fibular models is performed. These methods may be used to assist surgeons where commercial guides are not available.

Methods for designing a computer-aided design/computer-aided manufacturing (CAD/CAM) surgical guide are shown. Cutting planes are separated, united, and thickened to easily visualize the necessary bone transfer. These designs can be three-dimensional printed and checked for accuracy.

Computer-aided design/computer-assisted manufacturing (CAD/CAM) is now being evaluated as a preparative technique for maxillofacial surgery. Because this ...

Three-Dimensional Printing of a Complex Aortic Anomaly

Complex congenital aortic anomalies include diverse types of malformations that may be clinically asymptomatic or present with respiratory or esophageal symptoms. These anomalies may be associated with other congenital heart diseases. It is hard to identify the accurate anatomic vessel location from two-dimensional imaging data, such as computed tomography. As an additive manufacturing method, three-dimensional (3-D) printing can covert the acquired imaging data into 3-D physical models. This protocol describes the procedure for modeling the volumetric DICOM imaging into 3-D data and printing it as an anatomically realistic 3-D model. Using this model, surgeons can identify the vessel location of complex aortic anomalies, which is helpful for pre-operative planning and intra-operative guidance.

Here, we present a protocol to use three dimensional printed models for pre-operative planning and intra-operative reorganization of complicated vascular locations when handling a congenital aortic anomaly.

Complex congenital aortic anomalies include diverse types of malformations that may be clinically asymptomatic or present with respiratory or esophageal ...

A Postoperative Evaluation Guideline for Computer-Assisted Reconstruction of the Mandible

Valid comparisons of postoperative accuracy results in computer-assisted reconstruction of the mandible are difficult due to heterogeneity in imaging modalities, mandibular defect classification, and evaluation methodologies between studies. This guideline uses a step-by-step approach guiding the process of imaging, classification of mandibular defects and volume assessment of three-dimensional (3D) models, after which a legitimized quantitative accuracy evaluation method can be performed between the postoperative clinical situation and the preoperative virtual plan. The condyles and the vertical and horizontal corners of the mandible are used as bony landmarks to define virtual lines in the computer-assisted surgery (CAS) software. Between these lines the axial, coronal, and both sagittal mandibular angles are calculated on both pre- and postoperative 3D models of the (neo)mandible and subsequently the deviations are calculated. By superimposing the postoperative 3D model to the preoperative virtually planned 3D model, which is fixed to the XYZ axis, the deviation between pre- and postoperative virtually planned dental implant positions can be calculated. This protocol continues and specifies an earlier publication of this evaluation guideline.

Here, we propose a practical, feasible and reproducible evaluation guideline for computer-assisted reconstruction of the mandible in order to create uniformity between studies regarding postoperative accuracy evaluation. This protocol continues and specifies an earlier publication of this evaluation guideline.

Valid comparisons of postoperative accuracy results in computer-assisted reconstruction of the mandible are difficult due to heterogeneity in imaging ...

Multicolor 3D Printing of Complex Intracranial Tumors in Neurosurgery

Three-dimensional (3D) printing technologies offer the possibility of visualizing patient-specific pathologies in a physical model of correct dimensions. The model can be used for planning and simulating critical steps of a surgical approach. Therefore, it is important that anatomical structures such as blood vessels inside a tumor can be printed to be colored not only on their surface, but throughout their whole volume. During simulation this allows for the removal of certain parts (e.g., with a high-speed drill) and revealing internally located structures of a different color. Thus, diagnostic information from various imaging modalities (e.g., CT, MRI) can be combined in a single compact and tangible object.
However, preparation and printing of such a fully colored anatomical model remains a difficult task. Therefore, a step-by-step guide is provided, demonstrating the fusion of different cross-sectional imaging data sets, segmentation of anatomical structures, and creation of a virtual model. In a second step the virtual model is printed with volumetrically colored anatomical structures using a plaster-based color 3D binder jetting technique. This method allows highly accurate reproduction of patient-specific anatomy as shown in a series of 3D-printed petrous apex chondrosarcomas. Furthermore, the models created can be cut and drilled, revealing internal structures that allow for simulation of surgical procedures.

The protocol describes the fabrication of fully colored three-dimensional prints of patient-specific, anatomical skull models to be used for surgical simulation. The crucial steps of combining different imaging modalities, image segmentation, three-dimensional model extraction, and production of the prints are explained.

Three-dimensional (3D) printing technologies offer the possibility of visualizing patient-specific pathologies in a physical model of correct dimensions. ...

Combining Augmented Reality and 3D Printing to Display Patient Models on a Smartphone

Augmented reality (AR) has great potential in education, training, and surgical guidance in the medical field. Its combination with three-dimensional (3D) printing (3DP) opens new possibilities in clinical applications. Although these technologies have grown exponentially in recent years, their adoption by physicians is still limited, since they require extensive knowledge of engineering and software development. Therefore, the purpose of this protocol is to describe a step-by-step methodology enabling inexperienced users to create a smartphone app, which combines AR and 3DP for the visualization of anatomical 3D models of patients with a 3D-printed reference marker. The protocol describes how to create 3D virtual models of a patient&rsquo;s anatomy derived from 3D medical images. It then explains how to perform positioning of the 3D models with respect to marker references. Also provided are instructions for how to 3D print the required tools and models. Finally, steps to deploy the app are provided. The protocol is based on free and multi-platform software and can be applied to any medical imaging modality or patient. An alternative approach is described to provide automatic registration between a 3D-printed model created from a patient&rsquo;s anatomy and the projected holograms. As an example, a clinical case of a patient suffering from distal leg sarcoma is provided to illustrate the methodology. It is expected that this protocol will accelerate the adoption of AR and 3DP technologies by medical professionals.

Presented here is a method to design an augmented reality smartphone application for the visualization of anatomical three-dimensional models of patients using a 3D-printed reference marker.

Augmented reality (AR) has great potential in education, training, and surgical guidance in the medical field. Its combination with three-dimensional (3D) ...

3D Planning and Printing of Patient Specific Implants for Reconstruction of Bony Defects

We are in the midst of the 3D era in most aspects of life, and especially in medicine. The surgical discipline is one of the major players in the medical field using the constantly developing 3D planning and printing capabilities. Computer-assisted design (CAD) and computer assisted manufacturing (CAM) are used to describe the 3D planning and manufacturing of the product. The planning and manufacturing of 3D surgical guides and reconstruction implants is performed almost exclusively by engineers. As technology advances and software interfaces become more user-friendly, it raises a question regarding the possibility of transferring the planning and manufacturing to the clinician. The reasons for such a shift are clear: the surgeon has the idea of what he wants to design, and he also knows what is feasible and could be used in the operating room. It allows him to be prepared for any scenario/unexpected results during the operation and allows the surgeon to be creative and express his new ideas using the CAD software. The purpose of this method is to provide clinicians with the ability to create their own surgical guides and reconstruction implants. In this manuscript, a detailed protocol will provide a simple method for segmentation using segmentation software and implant planning using a 3D design software. Following the segmentation and stl file production using segmentation software, the clinician could create a simple patient specific reconstruction plate or a more complex plate with a cradle for bone graft positioning. Surgical guides can be created for accurate resection, hole preparation for proper reconstruction plate positioning or for bone graft harvesting and re-contouring. A case of lower jaw reconstruction following plate fracture and nonunion healing of a trauma sustained injury is detailed.

This protocol describes the use of 3D planning and printing for reconstruction of bony defects. We use segmentation tools to create 3D models followed by 3D design software to create patient specific implants for reconstruction purposes concomitant to ablative surgery or as a second stage.

We are in the midst of the 3D era in most aspects of life, and especially in medicine. The surgical discipline is one of the major players in the medical ...

Development and Evaluation of 3D-Printed Cardiovascular Phantoms for Interventional Planning and Training

Catheter-based interventions are standard treatment options for cardiovascular pathologies. Therefore, patient-specific models could help training physicians&#39; wire-skills as well as improving planning of interventional procedures. The aim of this study was to develop a manufacturing process of patient-specific 3D-printed models for cardiovascular interventions.
To create a 3D-printed elastic phantom, different 3D-printing materials were compared to porcine biological tissues (i.e., aortic tissue) in terms of mechanical characteristics. A fitting material was selected based on comparative tensile tests and specific material thicknesses were defined. Anonymized contrast-enhanced CT-datasets were collected retrospectively. Patient-specific volumetric models were extracted from these datasets and subsequently 3D-printed. A pulsatile flow loop was constructed to simulate the intraluminal blood flow during interventions. Models&#39; suitability for clinical imaging was assessed by x-ray imaging, CT, 4D-MRI and (Doppler) ultrasonography. Contrast medium was used to enhance visibility in x-ray-based imaging. Different catheterization techniques were applied to evaluate the 3D-printed phantoms in physicians&#39; training as well as for pre-interventional therapy planning.
Printed models showed a high printing resolution (~30 &#181;m) and mechanical properties of the chosen material were comparable to physiological biomechanics. Physical and digital models showed high anatomical accuracy when compared to the underlying radiological dataset. Printed models were suitable for ultrasonic imaging as well as standard x-rays. Doppler ultrasonography and 4D-MRI displayed flow patterns and landmark characteristics (i.e., turbulence, wall shear stress) matching native data. In a catheter-based laboratory setting, patient-specific phantoms were easy to catheterize. Therapy planning and training of interventional procedures on challenging anatomies (e.g., congenital heart disease (CHD)) was possible.
Flexible patient-specific cardiovascular phantoms were 3D-printed, and the application of common clinical imaging techniques was possible. This new process is ideal as a training tool for catheter-based (electrophysiological) interventions and can be used in patient-specific therapy planning.

Here we present development of a mock circulation setup for multimodal therapy evaluation, pre-interventional planning, and physician-training on cardiovascular anatomies. With the application of patient-specific tomographic scans, this setup is ideal for therapeutic approaches, training, and education in individualized medicine.

Catheter-based interventions are standard treatment options for cardiovascular pathologies. Therefore, patient-specific models could help training ...

Digital Hybrid Model Preparation for Virtual Planning of Reconstructive Dentoalveolar Surgical Procedures

Virtual, hybrid three-dimensional (3D) model acquisition is presented in this article, utilizing the sequence of radiographic image segmentation, spatial registration, and free-form surface modeling. Firstly cone-beam computed tomography datasets were reconstructed with a semi-automatic segmentation method. Alveolar bone and teeth are separated into different segments, allowing 3D morphology, and localization of periodontal intrabony defects to be assessed. The severity, extent, and morphology of acute and chronic alveolar ridge defects are validated concerning adjacent teeth. On virtual complex tissue models, positions of dental implants can be planned in 3D. Utilizing spatial registration of IOS and CBCT data and subsequent free-form surface modeling, realistic 3D hybrid models can be acquired, visualizing alveolar bone, teeth, and soft tissues. With the superimposition of IOS and CBCT soft tissue, thickness above the edentulous ridge can be assessed about the underlying bone dimensions; therefore, flap design and surgical flap management can be determined, and occasional complications may be avoided.

A workflow for creating three-dimensional (3D) virtual hybrid models has been designed based on cone-beam computed tomography dataset and intraoral optical scans utilizing radiographic image segmentation methods and free-form surface modeling. Digital models are used for the virtual planning of reconstructive dentoalveolar surgical procedures.

Virtual, hybrid three-dimensional (3D) model acquisition is presented in this article, utilizing the sequence of radiographic image segmentation, spatial ...

The Use of Mixed Reality in Custom-Made Revision Hip Arthroplasty: A First Case Report

The technology of 3D printing and visualization of anatomical structures is rapidly growing in various fields of medicine. A custom-made implant and mixed reality were used to perform complex revision hip arthroplasty in January 2019. The use of mixed reality allowed for a very good visualization of the structures and resulted in precise implant fixation. According to the authors' knowledge, this is the first described case report of the combined use of these two innovations. The diagnosis preceding the qualification for the procedure was the loosening of the left hip's acetabular component. Mixed reality headset and holograms prepared by engineers were used during the surgery. The operation was successful, and it was followed by early verticalization and patient rehabilitation. The team sees opportunities for technology development in joint arthroplasty, trauma, and orthopedic oncology.

A complex revision hip arthroplasty was performed using a custom-made implant and mixed reality technology. According to the authors&#39; knowledge, this is the first report of such procedure described in the literature.

The technology of 3D printing and visualization of anatomical structures is rapidly growing in various fields of medicine. A custom-made implant and mixed ...