Ferrari, Ana Lya Moya, Piculo dos Santos, Aline Darc, Bertolaccini, Guilherme da Silva, Medola, Fausto Orsi, and Sandnes, Frode Eika
Ferrari, A.L.M., Piculo dos Santos, A.D., Bertolaccini, G.S., Medola, F.O. & Sandnes, F.E. (2020). Evaluation of orthosis rapid prototyping during the design process: Analysis of verification models. In: M. Di Nicolantonio, E. Rossi & T. Alexander (Eds.), Advances in additive manufacturing, modeling systems and 3D prototyping: Proceedings of the AHFE 2019 International Conference on Additive Manufacturing, Modeling Systems and 3D Prototyping, Cham: Springer (pp. 298-307)
Usó, Vanessa Ghiraldeli, Sandnes, Frode Eika, and Medola, Fausto Orsi
Usó, V.G., Sandnes, F.E. & Medola, F.O. (2020). Using virtual reality and rapid prototyping to co-create together with hospitalized children. In: M. Di Nicolantonio, E. Rossi & T. Alexander (Eds.). Advances in additive manufacturing, modeling systems and 3D prototyping: Proceedings of the AHFE 2019 International Conference on Additive Manufacturing, Modeling Systems and 3D Prototyping, 2020 (pp. 279-288) Cham: Springer
Journal of Medical Systems. May 2019, Vol. 43 Issue 5, p1, 9 p.
Time to market, Product development, Thermoplastics, Sleep apnea syndromes, and Home appliances
Obstructive Sleep apnea is a public health problem. This disease is associated with daytime sleepiness, increased motor vehicle accidents, heart failure and stroke. Treatment options include weight loss, positive airway pressure, pharyngeal and orthognatic surgery. However, selected patients have good response to oral appliances devices that intended to protrude and stabilize the mandible mechanically during the night in order to reduce the collapsibility of the upper airway. Selection of patients includes primary snoring, mild, moderate and positional apnea. The perfect mandibular advance device has not yet been designed. For these reasons, the objective of this paper is to present a new thermoadjustable chair-side oral appliance. Device integrates the best characteristics of custom made and boils and bite previous designs and minimizes inconveniences and possible side effects. The device is a titratable mandibular advancement appliance. It consists of two independent prefabricated trays adaptable to the shape of adult dental arch and linked to each other by a protrusion mechanism. Each tray contains a hard outer shell and a soft thermoplastic resin inner body. The position of the jaw can be adjusted by moving an aluminum rack into, or out from, the guide so the ratchet may get locked into a certain position ensuring the length of the mechanism. The protrusion mechanism is fixed to the splint using small rings that are articulated over a 't' button. Our prototype satisfies the requirements of an effective oral appliance, in terms of retention, comfort, safety and efficacy. It is easy to fit, durable, low cost, quickly titratable, not bulky and easy cleaning. Thermoplastic appliances are specially used like a predictor of treatment response in apnea patients. The device described is a cost-effective introduction to mandibular advancement technology. A qualified dentist or trained sleep doctor could mitigate dental side effects and reduce their incidence.
Biomedical Engineering. July 2017, Vol. 51 Issue 2, p106, 5 p.
3D printing -- Analysis, Nervous system -- Surgery, and Nervous system -- Analysis
Introduction Cranioplasty is the second most commonly performed neurosurgical operation in history after trepanning; it continues to be very relevant despite the development of civilization and improvements in medical science. [...] The methods of three-dimensional printing widely used in the Russian Federation are discussed: FDM, SLA, SLS, and DMLS. Our own experience with three-dimensional modeling and prototyping of implants for reconstructive neurosurgical procedures is analyzed. An optimal method for three-dimensional printing of implants by direct laser metal sintering is developed and supported by evidence.
Lozano, Maria Teresa Ugidos, Haro, Fernando Blaya, Diaz, Carlos Molino, Manzoor, Sadia, Ugidos, Gonzalo Ferrer, and Mendez, Juan Antonio Juanes
Journal of Medical Systems. May 2017, Vol. 41 Issue 5, p1, 5 p.
3D printing -- Usage, 3D printing -- Study and teaching, Digitization -- Usage, Digitization -- Study and teaching, Human anatomy -- Usage, and Human anatomy -- Study and teaching
The creation of new rapid prototyping techniques, low cost 3D printers as well as the creation of new software for these techniques have allowed the creation of 3D models of bones making their application possible in the field of teaching anatomy in the faculties of Health Sciences. The 3D model of cranium created in the present work, at full scale, present accurate reliefs and anatomical details that are easily identifiable by undergraduate students in their use for the study of human anatomy. In this article, the process of scanning the skull and the subsequent treatment of these images with specific software until the generation of 3D model using 3D printer has been reported.
Bhatla, Puneet, Tretter, Justin T., Ludomirsky, Achi, Argilla, Michael, Latson, Larry A., Chakravarti, Sujata, Barker, Piers C., Yoo, Shi-Joon, McElhinney, Doff B., Wake, Nicole, and Mosca, Ralph S.
Pediatric Cardiology. Jan 2017, Vol. 38 Issue 1, p103, 12 p.
Congenital heart disease -- Care and treatment and Congenital heart disease -- Research
Rapid prototyping facilitates comprehension of complex cardiac anatomy. However, determining when this additional information proves instrumental in patient management remains a challenge. We describe our experience with patient-specific anatomic models created using rapid prototyping from various imaging modalities, suggesting their utility in surgical and interventional planning in congenital heart disease (CHD). Virtual and physical 3-dimensional (3D) models were generated from CT or MRI data, using commercially available software for patients with complex muscular ventricular septal defects (CMVSD) and double-outlet right ventricle (DORV). Six patients with complex anatomy and uncertainty of the optimal management strategy were included in this study. The models were subsequently used to guide management decisions, and the outcomes reviewed. 3D models clearly demonstrated the complex intra-cardiac anatomy in all six patients and were utilized to guide management decisions. In the three patients with CMVSD, one underwent successful endovascular device closure following a prior failed attempt at transcatheter closure, and the other two underwent successful primary surgical closure with the aid of 3D models. In all three cases of DORV, the models provided better anatomic delineation and additional information that altered or confirmed the surgical plan. Patient-specific 3D heart models show promise in accurately defining intra-cardiac anatomy in CHD, specifically CMVSD and DORV. We believe these models improve understanding of the complex anatomical spatial relationships in these defects and provide additional insight for pre/intra-interventional management and surgical planning.
Putrik, M.B., Lavrentyeva, Yu.E., and Antsygin, I.N.
Biomedical Engineering. July 2016, Vol. 50 Issue 2, p134, 4 p.
Medical imaging equipment and 3D printing
Introduction An object is 3D printed as follows . An STL file containing information on the three-dimensional image of the object is loaded into the 3D-printer. Then the image is [...] The application of rapid prototyping in medicine, in dentistry particularly, is described. The sequence of stages of initial data processing (set of digital images) for subsequent automated construction and 3D printing of objects is given. Examples of tooth impressions and surgical templates produced with different initial data parameters are described.
Ching, Wei-Cheng, Goh, Raymond C. W., Lin, Chun-Li, Lo, Lun-Jou, and Chen, Yu-Ray
Aesthetic Plastic Surgery. Dec 2011, Vol. 35 Issue 6, p1176, 4 p.
Surgery, Plastic -- Health aspects, Implants, Artificial -- Usage, Prosthesis -- Usage, and Rapid prototyping -- Usage
Skeletal deformity in the fronto-orbital region resulting from various problems can have significant aesthetic concerns. Restoring an aesthetically acceptable appearance relies most importantly on the restoration of a precise skeletal contour. Current surgical options for depression deformities or partial-thickness defects range from extensive corrective osteotomies to less complicated methods of onlay grafting with autogenous or alloplastic materials. Both methods have difficulties in providing a symmetric and smooth contour for predictable and reliable cosmetic results. Alloplastic implants provide another effective alternative and the success of the skeletal contouring correlates directly with the accuracy of the implant sculpture. Prefabricated methylmethacrylate implants, with the aid of modeling clay, computer imaging, and modern rapid-prototyping technologies, fits the depression deformity well and balances the skeletal contour. It provides plastic surgeons greater precision in customizing the implant, which ensures better predictability and reliability of cosmetic outcomes.
Non-invasive neuroimaging techniques enable extraordinarily sensitive and specific in vivo study of the structure, functional response and connectivity of biological mechanisms. With these advanced methods comes a heavy reliance on computer-based processing, analysis and interpretation. While the neuroimaging community has produced many excellent academic and commercial tool packages, new tools are often required to interpret new modalities and paradigms. Developing custom tools and ensuring interoperability with existing tools is a significant hurdle. To address these limitations, we present a new framework for algorithm development that implicitly ensures tool interoperability, generates graphical user interfaces, provides advanced batch processing tools, and, most importantly, requires minimal additional programming or computational overhead. Java-based rapid prototyping with this system is an efficient and practical approach to evaluate new algorithms since the proposed system ensures that rapidly constructed prototypes are actually fully-functional processing modules with support for multiple GUI's, a broad range of file formats, and distributed computation. Herein, we demonstrate MRI image processing with the proposed system for cortical surface extraction in large cross-sectional cohorts, provide a system for fully automated diffusion tensor image analysis, and illustrate how the system can be used as a simulation framework for the development of a new image analysis method. The system is released as open source under the Lesser GNU Public License (LGPL) through the Neuroimaging Informatics Tools and Resources Clearinghouse (NITRC).
Kacl, G. M., Zanetti, M., Amgwerd, M., Trentz, O., Seifert, B., Stucki, H., and Hodler, J.
European Radiology. March 1997, Vol. 7 Issue 2, p187, 5 p.
Rapid prototyping -- Analysis
The purpose of this study was to evaluate and compare the diagnostic performance of stereolithography vs workstation-based three-dimensional (3D) reformations in intra-articular calcaneal fractures. A total of 30 intra-articular calcaneal fractures were examined using standard radiographs, coronal CT scans, and 2D and 3D reformations. The CT data were transferred to an outside institution, and stereolithograms were produced from photopolymer resin employing a laser beam system. 3D reformations and stereolithograms were analyzed in a blinded fashion by two staff radiologists. Receiver-operating-characteristic (ROC) curves were obtained for six clinically significant fracture components. Standard radiographs, coronal CT scans, and 2D reformations served as the standard of reference. The area under the ROC curves for 3D reformations and stereolithograms were 1.0 and 0.98 for abnormal tuber angles, 0.91 and 0.91 for anterior and middle talo-calcaneal joint involvement, 0.90 and 0.95 for involvement of the posterior talo-calcaneal joint, 0.65 and 0.78 for the presence of a lateral bulge, 0.80 and 0.81 for the involvement of the calcaneocuboidal joint, and 0.62 and 0.67 for the presence of a 'tongue-type' fracture. No statistically significant difference was demonstrated for the two methods (Wilcoxon signed-rank test, p = 0.138). Based on our results stereolithograms did not prove to be statistically superior to workstation-based 3D reformations. Stereolithograms may still be useful for teaching purposes and for surgical planning at a thinking-efficacy level.
European Spine Journal. Dec 2010, Vol. 19 Issue 12, p2137, 12 p.
Clinical studies reported frequent failure with anterior instrumented multilevel cervical corpectomies. Hence, posterior augmentation was recommended but necessitates a second approach. Thus, an author group evaluated the feasibility, pull-out characteristics, and accuracy of anterior transpedicular screw (ATPS) fixation. Although first success with clinical application of ATPS has already been reported, no data exist on biomechanical characteristics of an ATPS-plate system enabling transpedicular end-level fixation in advanced instabilities. Therefore, we evaluated biomechanical qualities of an ATPS prototype C4--C7 for reduction of range of motion (ROM) and primary stability in a non-destructive setup among five constructs: anterior plate, posterior all-lateral mass screw construct, posterior construct with lateral mass screws C5 + C6 and end-level fixation using pedicle screws unilaterally or bilaterally, and a 360deg construct. 12 human spines C3--T1 were divided into two groups. Four constructs were tested in group 1 and three in group 2 the ATPS prototypes were tested in both groups. Specimens were subjected to flexibility test in a spine motion tester at intact state and after 2-level corpectomy C5--C6 with subsequent reconstruction using a distractable cage and one of the osteosynthesis mentioned above. ROM in flexion--extension, axial rotation, and lateral bending was reported as normalized values. All instrumentations but the anterior plate showed significant reduction of ROM for all directions compared to the intact state. The 360deg construct outperformed all others in terms of reducing ROM. While there were no significant differences between the 360deg and posterior constructs in flexion--extension and lateral bending, the 360deg constructs were significantly more stable in axial rotation. Concerning primary stability of ATPS prototypes, there were no significant differences compared to posterior-only constructs in flexion--extension and axial rotation. The 360deg construct showed significant differences to the ATPS prototypes in flexion--extension, while no significant differences existed in axial rotation. But in lateral bending, the ATPS prototype and the anterior plate performed significantly worse than the posterior constructs. ATPS was shown to confer increased primary stability compared to the anterior plate in flexion--extension and axial rotation with the latter yielding significance. We showed that primary stability after 2-level corpectomy reconstruction using ATPS prototypes compared favorably to posterior systems and superior to anterior plates. From the biomechanical point, the 360deg instrumentation was shown the most efficient for reconstruction of 2-level corpectomies. Further studies will elucidate whether fatigue testing will enhance the benefit of transpedicular anchorage with posterior constructs and ATPS.
Clin, Julien, Aubin, Carl-Eric, and Labelle, Hubert
Medical & Biological Engineering & Computing. May 2007, Vol. 45 Issue 5, p467, 7 p.
Finite element method -- Analysis and Finite element method -- Models
Based on a three-dimensional patient-specific finite element model of the spine, rib cage, pelvis and abdomen, a parametric model of a thoraco-lumbo-sacral orthosis (TLSO) was built. Its geometry is custom-fit to the patient. The rigid shell, pads and openings are all represented. The interaction between the trunk and the brace is modeled by a point-to-surface contact interface. During the nonlinear simulation process, the brace is opened, positioned on the patient and strap tension is applied. A TLSO similar to Boston brace system was built for a right-thoracic scoliotic patient. The influences of the trochanter pad and strap tension on the 3-D geometrical corrections and on the forces generated by the brace were evaluated. The role of the trochanter pad as a lever arm is confirmed by the model. The brace induces a reduction of the lordosis and pelvic tilt. The reduction of the frontal curvature is about 20% for a strap tension of 60 N. Axial rotation does not significantly change and rib hump is worsened. By using an explicit brace model and a contact interface, a more realistic simulation of orthotic treatment of scoliosis can be achieved. The stabilization of the brace on the patient can be represented and less restrictive boundary conditions can be applied. This model could be used to study the effect of design parameters on the brace efficiency.
Mukhopadhyay, A., Devulapalli, B., Dutta, A., and Grald, E. W.
JOM: Journal of The Minerals, Metals & Materials Society. March 2004, Vol. 56 Issue 3, p44, 5 p.
The use of computational fluid dynamics (CFD) software in many materials processing industries has grown tremendously in recent years. Computational fluid dynamics has been widely utilized for conducting virtual experiments, prototype testing, and parametric studies. Analysis using CFD complements and reduces physical testing, and it can result in a significant time and cost savings. In this article, the application of CFD to a variety of materials-processing problems is presented, with examples taken from the steel, aluminum, glass, semiconductor, and polymer processing fields.