CAD/CAM-MACHINABLE DISC FOR THE MANUFACTURE OF FIBER INLAY-CORES

Abstract

The invention concerns a preform for a CAD/CAM machining apparatus having an upper face and a lower face a11d in which at least one of the cells is filled with a composite material to be machined by CAD/CAM, said material comprising long unidirectional fibers embedded in a cross-linked polymer matrix.

Claims

1.-13. (canceled)

14. A preform for a CAD/CAM machining apparatus having an upper face and a lower face and comprising at least one cell filled with a composite material to be machined by CAD/CAM, said material comprising at least 80%, preferably 90%, more preferably 100% long unidirectional fibers embedded in a cross-linked polymer fiber matrix placed in the matrix vertical to the upper and lower faces of the support.

15. The preform according to claim 14, characterized in that the cells abut each surface of the support and in that the entire volume of the cells is filled with the composite material.

16. The preform according to claim 14, characterized in that the cells are cylindrical.

17. The preform according to claim 16, characterized in that the cells are 3 to 20 mm in diameter and preferably 10 to 24 mm deep.

18. The preform according to claim 14, characterized in that the support is in disc form, preferably 98 mm in diameter.

19. The preform according to claim 14, characterized in that the materials constituting the polymer matrix and the support are identical or compatible and chosen within the group of thermosetting resins containing PMMA, TEGDMA, BISGMA, BDMA, HDDMA, UDMA, epoxy and vinylester, or in the group of thermoplastic resins notably PC, POM, PU.

20. The preform according to claim 14, characterized in that the fibers are chosen from the group comprising glass fibers E, R, S, AR, and XRO, silica (quartz).

21. The preform according to claim 14, characterized in that the fibers represent 40 to 80%, preferably 60 to 70% by volume of the polymer matrix, supplemented by the matrix to 100%.

22. A process for fabricating the preform that is the object of claim 14, characterized in that into a mold: one positions the cylinders constituted of long longitudinal unidirectional fibers embedded in a cross-linked polymer matrix, one pours a resin between each cylinder, one cross-links said resin, one unmolds the preform formed from the cross-linked resin, including the rod portions.

23. An inlay core composite fiber constituted of long longitudinal unidirectional (UD) fibers embedded in a cross-linked polymer matrix.

24. The use of the preform according to claim 14 to manufacture the inlay core, tenons, or implant screws machined by CAD/CAM from composite material filling the cells.

Description

[0051] FIG. 1 is a perspective view of the support according to the invention.

[0052] A rod comprising 81% by weight (64% volume) of unidirectional glass fibers AR and 19% of epoxy resin matrix is manufactured by pultrusion. The rod diameter is 12 mm. The rods are cut into 16 mm sections.

[0053] Thirty 12 mm rod sections or nineteen 14 mm portions as marked are positioned in a mold that is 98 mm in diameter and 16 mm thick.

[0054] Then an acrylic resin cold-polymerized with a peroxide-based catalyst is poured into the mold.

[0055] Lastly, the support is unmolded. This includes the cells filled by the rod sections. The CAD/CAM then inserts a disc into a machining apparatus. To facilitate indexing in the CAD/CAM machine, each portion of the rod is marked. The CAD/CAM then machines each portion to obtain the inlay cores, tenons, or even implant screws. These structures are made of composite fibers wherein the fibers are longitudinal and unidirectional.

[0056] The support thus obtained is shown is FIG. 1. It constitutes the support itself (1) shown in disc form with each of its 23 cells filled with a rod section (2). Each portion of the rod is machined by the CAD/CAM. Depending on the diameter of the rods, the disc can contain more cells.

[0057] The invention and its advantages will be seen clearly in the following example. This is shown as a non-limiting example for the one skilled in the art. It is thereby shown that inlay cores of composite fibers can be manufactured using CAD/CAM.