Patient-Specific Three-Dimensional Composite Bone Models for Teaching and Operation Planning

Background: Orthopedic trauma care relies on two-dimensional radiograms both before and during the operation. Understanding the three-dimensional nature of complex fractures on plain radiograms is challenging. Modern fluoroscopes can acquire three-dimensional volume datasets even during an operation, but the device limitations constrain the acquired volume to a cube of only 12-cm edge. However, viewing the surrounding intact structures is important to comprehend the fracture in its context. We suggest merging a fluoroscope's volume scan into a generic bone model to form a composite full-length 3D bone model. Methods: Materials consisted of one cadaver bone and 20 three-dimensional surface models of human femora. Radiograms and computed tomography scans were taken before and after applying a controlled fracture to the bone. A 3D scan of the fracture was acquired using a mobile fluoroscope (Siemens Siremobil). The fracture was fitted into the generic bone models by rigid registration using a modified least-squares algorithm. Registration precision was determined and a clinical appraisal of the composite models obtained. Results: Twenty composite bone models were generated. Average registration precision was 2.0mm (range 1.6 to 2.6). Average processing time on a laptop computer was 35s (range 20 to 55). Comparing synthesized radiograms with the actual radiograms of the fractured bone yielded clinically satisfactory results. Conclusion: A three-dimensional full-length representation of a fractured bone can reliably be synthesized from a short scan of the patient's fracture and a generic bone model. This patient-specific model can subsequently be used for teaching, surgical operation planning, and intraoperative visualization purpose

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

Este número da revista Cadernos de Estudos Sociais estava em organização quando fomos colhidos pela morte do sociólogo Ernesto Laclau. Seu falecimento em 13 de abril de 2014 surpreendeu a todos, e particularmente ao editor Joanildo Burity, que foi seu orientando de doutorado na University of Essex, Inglaterra, e que recentemente o trouxe à Fundação Joaquim Nabuco para uma palestra, permitindo que muitos pudessem dialogar com um dos grandes intelectuais latinoamericanos contemporâneos. Assim, buscamos fazer uma homenagem ao sociólogo argentino publicando uma entrevista inédita concedida durante a sua passagem pelo Recife, em 2013, encerrando essa revista com uma sessão especial sobre a sua trajetória

Pelvic Fracture in a Cat - Precontouring of the Plate Based on Allogenic 3D Model and its Application

Background: Pelvic fractures are commonly ecountered in cats. The ilium is included in approximately 50% of pelvic fractures in cats. Although conservative management of the pelvic fracture is known to have good prognosis, surgical fixation is recommended for the pelvic fractue with ilial fractures. 3D printing is an accurate digital modeling method by converting two-dimensional (2D) image into 3D model. 3D printing in veterinary medicine have been described in the various orthopedic diseases such angular limb deformities or fractures. The use of 3D model for presurgical planning is helpful to improve the results of complex surgical interventions. The objective of this study is to identify the usefulness of fabricating 3D models based on allogenic 2D data with aid of 3D printer program. Case: A 4-year-old spayed female domestic shorthair cat presented with hindlimb lameness. Radiography revealed left ilial body fracture with multiple fractures including left tuber ischium, pubic symphysis, and bilateral cranial ramuses of pubis. Digital imaging and communication in medicine (DICOM) files of the complete ilium were extracted from a CT scan of a healthy and castrated male cat of same breed. Volume rendering images were prepared by Slicer program based on DICOM files. After acquired 3D data were converted to STL (Standard Triangulation Language) file for the 3D printing machine, non-fracture involved area was removed except the left ilium using the Meshmixer® soft-ware and then data was stored as STL files again. The length of 3D model was adjusted to actual size using 3D printer firmware based on actual size of the ilial length. Subsequently, 3D modelling was performed using 3D printer. The plate was precontoured to conform to the lateral surface of the 3D model. Internal fixation using precontoured plate resulted in accurate bone alignment. The alignment of the ilium remained appropriate throughtout the follow-up period. Complete union was identified 6 months after surgery. Discussion: Although the most common method for the ilial fractures is the application of bone plates to the lateral side of the ilium, bone plate fixation is more challenging in cats owing to the small bone size and small surface area of the fracture sites compared to dogs. Therefore, it is important to make accurate presurgical planning for successful result of a surgery. 3D printing based on actual patient have several limitations including time for complete printing process and additional anesthetic episode to acquire computed tomography (CT) images. However, in simple cases, a presurgical CT scan may not be necessary if the plate can be precisely precontured based on the data from the other patient. In this way, the additional financial burden for CT examination also might be reduced. On the other hand, technical difficulty of utilizing hardware and software, and financial availability were another drawback. However, in this current study, most of limitations regarding conventional 3D printing based on actual patient were overcome by the application of the fused deposition modeling (FDM) technology with allogenic data. In the current study, total time for fabrication of 3D model based on FDM technology, was less than 3 h, which are much shorter than the time for conventional 3D printing. The difference of the ilial length between the actual patient and the 3D model was adjusted through the firmware program. Thus, differences of the conformation or size between the 3D model and the ilium of the patient was negligible during the surgery, although 2D images were not acquired from actual patient. Intraoperative contouring of the plate was not required. In conclusion, through presurgical plate contouring by the 3D bone template based on non-patient specific data, successful treatment of the ilial fracture was possible. Keywords: allogenic; cats; ilial fracture; 3D printing, 3D models, pilot study

Rapid prototyping modelling in oral and maxillofacial surgery: a two year retrospective study

Background: The use of rapid prototyping (RP) models in medicine to construct bony models is increasing. Material and Methods: The aim of the study was to evaluate retrospectively the indication for the use of RP models in oral and maxillofacial surgery at Helsinki University Central Hospital during 2009-2010. Also, the used computed tomography (CT) examination – multislice CT (MSCT) or cone beam CT (CBCT) - method was evaluated. Results: In total 114 RP models were fabricated for 102 patients. The mean age of the patients at the time of the production of the model was 50.4 years. The indications for the modelling included malignant lesions (29%), secondary reconstruction (25%), prosthodontic treatment (22%), orthognathic surgery or asymmetry (13%), benign lesions (8%), and TMJ disorders (4%). MSCT examination was used in 92 and CBCT examination in 22 cases. Most of the models (75%) were conventional hard tissue models. Models with colored tumour or other structure(s) of interest were ordered in 24%. Two out of the 114 models were soft tissue models. Conclusions: The main benefit of the models was in treatment planning and in connection with the production of pre-bent plates or custom made implants. The RP models both facilitate and improve treatment planning and intraoperative efficiency

Additive manufacturing applications in medical cases: A literature based review

Background: A significant number of the research paper on Medical cases using Additive manufacturing studied. Different applications of additive manufacturing technologies in the medical area analysed for providing the state of the art and direction of the development.The aim of work: To illustrate the Additive Manufacturing technology as being used in medical and its benefits along-with contemporary and future applications.Materials and methods: Literature Review based study on Additive Manufacturing that are helpful in various ways to address medical problems along with bibliometric analysis been done.Result: Briefly described the review of forty primary applications of AM as used for medical purposes along with their significant achievement. Process chain development in the application of AM is identified and tabulated for every process chain member, its achievement and limitations for various references. There are five criteria which one can achieve through medical model when made through AM technology. To support the achievements and limitations of every criterion proper references are provided. The ongoing research is also classified according to the application of AM in medical with criteria, achievement and references. Eight major medical areas where AM is implemented have been identified along with primary references, objectives and advantages.Conclusion: Paper deals with the literature review of the Medical application of Additive Manufacturing and its future. Medical models which are customised and sourced from data of an individual patient, which vary from patient to patient can well be modified and printed. Medical AM involves resources of human from the field of reverse engineering, medicine and biomaterial, design and manufacturing of bones, implants, etc. Additive Manufacturing can help solve medical problems with extensive benefit to humanity.Keywords: 3D scanning, 3D printing, Additive Manufacturing (AM), Medical, Applications, Medical model, Rapid Prototyping (RP

New frontiers and emerging applications of 3D printing in ENT surgery: A systematic review of the literature

3D printing systems have revolutionised prototyping in the industrial field by lowering production time from days to hours and costs from thousands to just a few dollars. Today, 3D printers are no more confined to prototyping, but are increasingly employed in medical disci- plines with fascinating results, even in many aspects of otorhinolaryngology. All publications on ENT surgery, sourced through updated electronic databases (PubMed, MEDLINE, EMBASE) and published up to March 2017, were examined according to PRISMA guidelines. Overall, 121 studies fulfilled specific inclusion criteria and were included in our systematic review. Studies were classified according to the specific field of application (otologic, rhinologic, head and neck) and area of interest (surgical and preclinical education, customised surgical planning, tissue engineering and implantable prosthesis). Technological aspects, clinical implications and limits of 3D printing processes are discussed focusing on current benefits and future perspectives

LLUSD Articulator - Volume 30, Number 2

Contents: 6 | Dean\u27s Circle member assemble at ESRI11 | PNAM celebrates tenth anniversary15 | From street life to restoration18 | Applications for 3D printing in dentistry25 | LLUSD research publications31 | Riverside\u27s fifth Long Night35 | Profiling Lee Ingersollhttps://scholarsrepository.llu.edu/articulator/1017/thumbnail.jp