Since the strength of personalized poly-ether-ether-ketone(PEEK)skull implants fabricated by material increasing manufacturing is lower than that by injection molding
a novel method of multi-point flexible molding is proposed to solve this problem by combining injection molding with material increasing manufacturing. The continuous planes are discretized
and a large number of movable square needles are used to construct the flexible molding cavity surface by means of profiling. A personalized PEEK skull blank is then fabricated by injection molding
and the personalized PEEK skull implant is fabricated after the blank is polished. It is found that the average accuracy of the skull samples is in the range from 0.475 to -0.409 mm
and the tensile strength of the samples is within 72.15 MPa and 83.26 MPa
which can meet the requirement of implant for accuracy and mechanical property. In the cell toxicity experiment
the survival rates of the cells in the raw material leach liquor and the injection sample leach liquor are detected higher than 90%
which proves that the material used in multi-point flexible molding is nontoxic
and no new toxic substances are introduced into the injection molding. So multi-point flexible molding can meet the requirement of implant for biocompatibility. The method of multi-point flexible molding can be chosen to fabricate personalized skull with lower cost and perfect performance
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