Rosa, Everton Luis Santos da, Oleskovicz, César Fernando, and Aragão, Bruno Nogueira
Brazilian Dental Journal. December 2004 15(3):243-247
DENTISTRY, ORAL SURGERY & MEDICINE, rapid prototyping, stereolithography, and maxillofacial surgery
Review of the literature from 1991 to 2002 on the use of rapid prototyping in the biomedical area emphasizes the applicability of this technique to aid diagnosis and planning in Maxillofacial Surgery and Traumatology. A case report in which a TMJ ankylosis relapse was treated using rapid prototyping (selective laser sintering) for surgery planning is presented. After one year, the patient's buccal opening was 45 mm. Transitory paralysis of the facial nerve disappeared totally in six months. Apresenta-se uma revisão da literatura (1991 a 2002) sobre a utilização da prototipagem rápida em biomedicina enfatizando-se a aplicabilidade da mesma em Cirurgia e Traumatologia Bucomaxilofacial. O planejamento cirúrgico de um caso de recidiva de anquilose da ATM foi realizado com o emprego da prototipagem rápida (sinterelização seletiva a laser). Após um ano da cirurgia a abertura bucal máxima estava em 45 mm. A paralisia transitória do nervo facial desapareceu totalmente em seis meses.
Paiva, Wellingson Silva, Amorim, Robson, Bezerra, Douglas Alexandre França, and Masini, Marcos
Arquivos de Neuro-Psiquiatria. June 2007 65(2b):443-445
NEUROSCIENCES, PSYCHIATRY, spine surgery, rapid prototyping, stereolithography, cirurgia da coluna, prototipagem rápida, and estereolitografia
Many techniques have been proposed for surgical training as a learning process for young surgeons or for the simulation of complex procedures. Stereolithograpfy, a rapid prototyping technique, has been presented recently as an option for these purposes. We describe the case of a 12 years old boy, diagnosed with Ewing´s sarcoma in the cervical spine. After a surgical simulation accomplished in the prototype, built by stereolithography, the patient was submitted to a C4 corpectomy and to a C4 and C3 laminectomy with anterior and posterior fixation, a non intercurrence procedure. This technique is an innovative and complementary tool in diagnosis and therapy. As a result, it is easier for the surgeon to understand the complexity of the case and plan the approach before any surgical procedure. Lesões tumorais da coluna podem representar um grande desafio para equipe cirúrgica. A estereolitografia é uma técnica de construção de peças anatômicas a partir de desenhos gráficos ou exames radiológicos. Apresentamos um paciente de 12 anos, com quadro de cervicobraquialgia à direita com diagnóstico de sarcoma de Ewing. Ao exame neurológico, o paciente apresentava-se com paresia em MSD grau IV e leve hipoestesia em dermátomos de C6 à T1 à direita. RM evidenciou edema intra e extra-ósseo com compressão medular e instabilidade cervical. Realizada simulação cirúrgica no protótipo construído por estereolitografia. Foi submetido a corpectomia de C4 e a laminectomia C4 e C3, com fixação anterior e posterior, procedimento sem intercorrências. A estereolitografia é ferramenta inovadora no auxílio diagnóstico e terapêutico. Seu uso permite ao cirurgião entender fisicamente o sítio da lesão, estudar a via de acesso e perceber a real complexidade do caso antes do procedimento cirúrgico.
The utilization of stereolithography molds in the manufacture pre-series for injection molded plastic parts aims to reduce costs throughout the product life-time, but mainly during design and manufacturing phases. The use of this Rapid Tooling technique in powder metal injection molding is evaluated in this work. One of the greatest differences between traditional and stereolithography tools is related to the heat conductivity of the materials employed. For example, steel molds have a heat conductivity coefficient 300 times higher than molds made with the photosensitive resin used in the stereolithography process. The discrepancy regarding the cooling rate of the molded parts during the injection cycle must be compensated with adjustments in the injection molding parameters, such as temperature, pressure and speed. The optimization of these parameters made it possible to eject green parts from the mold without causing defects which would become evident in debinding and sintering stages. The dimensional analysis performed at the end of each case study showed that the shrinking factor of the component after the sintering had the same value obtained for components using traditional metallic molds. Moreover, the dimensional error remains under 2% which can be considered low for a pre-series of components (or prototype series).
Gaspar, M., Alves, N., Mateus, A., and Martins-Ferreira, N.
Rapid Prototyping, Stereolithography, Containment, Packing, and Optimization
Given multiple identical polyhedral objects and a parallelepiped container, how should one place the objects so that the largest number fits inside the container? This simple question is important in many applications, yet the answer is elusive. In fact, we know of no published solution for this very general formulation. Still, in many circumstances, further restrictions apply, resulting in a large number of variations requiring different algorithmic strategies. This paper is the continuation of  and focus on the fundamental concepts and tools that are used for this kind of problem, such as the no-fit polygon. We also present some of its many variations, giving in particular one that applies to the stereolithographic rapid prototyping technology.
Salmoria, Gean Vitor, Lafratta, Fernando H., Biava, Matheus M., Ahrens, Carlos Henrique, and Ferreira, Pedro Z.
Journal of the Brazilian Society of Mechanical Sciences and Engineering. March 2008 30(1):7-10
ENGINEERING, MECHANICAL, stereolithography, miniaturized parts, and rapid tooling
Currently, miniaturization is a major trend in the manufacturing and commercialization of new industrial products. When small-sized objects should be manufactured with dimensions of only a few millimeters or less, many difficulties can appear using traditional processes. An alternative to study these new requirements is through the use of rapid prototyping technologies. Stereolithography (SL) has established itself as one of the most popular and reliable process allowing the rapid manufacturing of complex parts. This paper investigates the SL process, which directly produces small parts by rapid manufacturing, and also indirectly by rapid tooling. The processability of small parts was investigated using two different shapes. The POM and ABS materials were used in the indirect manufacturing. The dimensional accuracy, precision and tolerance of micro parts were evaluated using metrological techniques. Results showed accuracy and precision greater than 97% when small-parts are manufactured directly by Stereolithography.