**3.3 Implant fabrication**

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Fig. 11. One digital layer as represented in EBM Control software (black part is fused and

Fig. 10. Packing of implants for more efficient fabrication.

white left unfused).

Once the pre-processing is done, implants are manufactured layer by layer on the machine. In the case of EBM, as mentioned before, the printing of the layers is done by the action of electron beam which performs a selective melting of material (fuses the black part on Figure 10 and leaves unfused the white part). The electron beam is very powerful and has a diameter of approximately 240 microns, which makes the contour of the layer – that is the surface of the implant when finished - a bit rough (Figure 12). This implies additional postprocessing in the zones of the implant that need smooth surface. However, in order to get better surface quality, the technology has suffered some changes recently and a *Multibeam®* strategy has been introduced (Figure 12).

Fig. 12. Multibeam® strategy for better implant surface quality (left), fusing the layer (right)
