Fabrication of a wax ear by rapid-process modeling using stereolithography.

PURPOSE: The purpose of this article is to describe an automated technique that creates a mirror-image wax model of the contralateral ear using a rapid prototyping technique, which allows precise positioning and adaptation to the deficient side of the face.
MATERIALS AND METHODS: Magnetic resonance images (MRI) are taken of the face and then digitized and reformatted into a 3-dimensional image. The image of the normal ear is extracted, mirrored, and positioned onto the image of the deformed side of the face. The digitized data, when used in conjunction with stereolithography, produces a photopolymerized resin model ear. A model wax ear is created by pouring molten wax into a silicone mold of the resin model ear.
RESULTS: A model wax ear of identical dimensions, shape, and internal contouring as the contralateral normal ear is created. The technique allows the undersurface of the model wax ear to be precisely positioned against the surface contours of the deformed side of the face in 1 patient.
CONCLUSION: The use of stereolithography from MRI scan data is a suitable technique for producing a model wax ear that fits the deformed side of the face. The 3-dimensional computer image of the face may also be used to plan the position (level and protrusion) of the ear.