New Technology May Revolutionize Device Development
BY LAUREN UZDIENSKI, NOVEMBER 2, 2006
With limitations of time and money, designing a "perfect" medical device may be an unattainable goal. Practical limitations prompt designers stop at adequate designs lacking forseeable flaws - but new technology can give designers more freedom to test and develop new devices.
Rapid prototyping allows designers to experiment with different shapes, materials and components, enabling designers to test multiple ideas and simplifying minor adjustments. Rapid prototyping refers to the process of forming an object layer by layer, as opposed to the more traditional ("subtractive") method of cutting a raw material down to the desired shape. Because many orthopedic devices are made from metal, and additive technology is more effective with non-metallic substances, rapid prototyping has not yet had a significant impact on device design. However, as new materials, such as ceramics, gain popularity, rapid prototyping will take on a bigger role. We saw hints of this at the ODT Conference, where rapid prototyping was a hot topic.
Below is a summary of some common additive fabrication processes:
Steroeolithography (SLA)
Using a CAD program, an object is created in liquid plastic. This is used in orthopedics to test the "feel" of a prototype instrument.
Selective laser sintering (SLS)
Layer by layer, a high-powered laser fuses plastic, metal or ceramic into a 3-D object.
Fused deposition modeling (FDM)
Material is layered with a heated nozzle that can move vertically or horizontally. It can use plastics of engineering grade, but in general, FDM parts are not as functional or as detailed as a machined part.
Solid Ground Curing
Like SLA, solid ground curing builds a product in layers of plastic. However, the layers are hardened all at once, instead of one at a time, making the process faster than that of SLA.
While rapid prototyping is still in the early stages of its contribution to orthopedics, it reflects an exciting opportunity: technology that can encourage a safer, more innovative product line.
