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Purpose:The purpose of this study was to compare the accuracy, required time, and
potential advantages of rapid prototyping technology with traditional methods in the
manufacture of wax patterns for two facial prostheses. Materials and Methods:Two
clinical situations were investigated: the production of an auricular prosthesis and the
duplication of an existing maxillary prosthesis, using a conventional and a rapid
prototyping method for each. Conventional wax patterns were created from impressions
taken of a patient’s remaining ear and an oral prosthesis. For the rapid prototyping
method, a cast of the ear and the original maxillary prosthesis were scanned, and rapid
prototyping was used to construct the wax patterns. For the auricular prosthesis, both
patterns were refined clinically and then flasked and processed in silicone using routine
procedures. Twenty-six independent observers evaluated these patterns by comparing
them to the cast of the patient’s remaining ear. For the duplication procedure, both wax
patterns were scanned and compared to scans of the original prosthesis by generating
color error maps to highlight volumetric changes. Results:There was a significant
difference in opinions for the two auricular prostheses with regard to shape and esthetic
appeal, where the hand-carved prosthesis was found to be of poorer quality. The color
error maps showed higher errors with the conventional duplication process compared
with the rapid prototyping method. Conclusion:The main advantage of rapid
prototyping is the ability to produce physical models using digital methods instead of
traditional impression techniques. The disadvantage of equipment costs could be
overcome by establishing a centralized service. Int J Prosthodont 2004;17:454–459.
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