Digital manufacture of titanium prosthesis for cranioplasty

Based on multi-point forming (MPF) technology, a novel digital manufacturing method of cranial titanium plates for the repair of skull defects is developed in this paper. First, a 3D triangular mesh model of the skull is constructed from a CT data set. Then, a non-uniform rational B-splines-format (NURBS-format) patch surface is obtained by surface interpolation based on the skull polygon model. Finally, the patch surface model is input to MPF CAD/CAM software and the cranial titanium prosthesis is deformed by an MPF press. The method has many new features compared with other means. Implementing medical image processing and MPF technology, the method can remarkably shorten the production cycle of titanium cranioplasty, as well as offer improved fitting precision. About 20 practical applications have been finished, which prove the feasibility and efficiency of the method.