Content area
Full Text
Introduction
Over the last decade, reverse engineering, computer-aided design, computer-aided manufacturing and rapid prototyping (RE, CAD, CAM, and RP) have been employed in medicine and dentistry ([2] Gibson, 2005). Diagnostic tools have become increasingly more sophisticated and medical imaging technology can now present patient data with high precision. Virtual planning environments allow data visualization and manipulation. With RP, there came a way to produce custom physical models of patient anatomy providing doctors the means for tactile interaction which facilitates preoperative planning of complex surgeries. In addition, RP-generated replicas act often as a basis for customization of treatment devices such as craniofacial plates. RP-techniques are also used to create custom treatment aides such as dental drilling guides that transfer the digital planning to the patient in a reliable way. Because of technical improvements of layer manufacturing (LM) processes and due to the possibility to process all kind of metals, RP evolved to rapid manufacturing (RM) in recent years ([8] Levy et al. , 2003; [4], [6], [7] Kruth et al. , 2005a, b, c). Medical and dental applications could take advantage of this evolution by using LM techniques not only for plastic devices like visual anatomical models or one-time surgical guides, but also for functional implants or prostheses with long-term consistency made from a biocompatible metal.
This paper discusses the use of selective laser melting (SLM) as a RM technique for medical applications. SLM is a layer-wise material addition technique that allows generating complex 3D parts by selectively melting successive layers of metal powder on top of each other, using the thermal energy supplied by a focused and computer controlled laser beam ([9] Over et al. , 2002; [4], [6], [7] Kruth et al. , 2005a, b, c). Medical and dental applications are very suitable to be produced by SLM due to their complex geometry, strong individualization and high-aggregate price. Moreover, the manufacturing of multiple unique parts in a single production run could enable mass customization.
To turn SLM into a manufacturing technique for implants or prostheses, some important conditions have to be fulfilled. The laser-melted parts have to meet strict material requirements regarding mechanical and chemical properties and the process must guarantee high accuracy and appropriate surface roughness. In this study, the SLM process has...