Implant Production Method Using Additive Selective Laser Sintering, and Implant

Abstract

The invention relates to a method for producing an implant, wherein particles of the group of ultra-high molecular weight polyethylene (UHMWPE) and/or high-density polyethylene (HDPE) and/or polypropylene (PP) are fused together layer by layer by means of a selective laser sintering method. The invention also relates to an implant produced according to said method.

Claims

1. A method for producing an implant, wherein particles of the group of ultra-high molecular weight polyethylene (UHMWPE) and/or high-density polyethylene (HDPE) and/or polypropylene (PP) are fused together layer by layer by means of a selective laser sintering method, wherein a heat treatment is carried out after the selective laser sintering such that the pores of the implant to be produced remain unsealed or open and/or a heat treatment is carried out after the selective laser sintering such that the pores of the implant to be produced are superficially sealed in total or in partial areas only.

2. The method according to claim 1, wherein the particles are fused together for forming a massive body or a porous body including entrapped air.

3. The method according to claim 2, wherein the body has a complex geometry.

4. The method according to claim 1, wherein the particles have a potato-like or sphere-like shape.

5. The method according to claim 4, wherein the particles in powder form have a diameter between about 20 m and about 300 m.

6. The method according to claim 5, wherein the particles present as powder grains have a diameter between about 130 m and about 150 m.

7. The method according to claim 1, wherein a surface treatment is carried out in the form of a plasma treatment, a snow blasting, a pressurized bombarding by frozen CO.sub.2 flakes or a ultrasonic bath.

8. (canceled)

9. An implant produced according to the method of claim 1.

10. The implant according to claim 9, wherein the implant is formed as a CMF implant for reconstruction of a cartilage and/or bone component for a human body.

11. An implant produced according to the method of claim 2.

12. The implant according to claim 11, wherein the implant is formed as a CMF implant for reconstruction of a cartilage and/or bone component for a human body

13. An implant produced according to the method of claim 3.

14. The implant according to claim 13, wherein the implant is formed as a CMF implant for reconstruction of a cartilage and/or bone component for a human body

15. An implant produced according to the method of claim 4.

16. The implant according to claim 15, wherein the implant is formed as a CMF implant for reconstruction of a cartilage and/or bone component for a human body

17. An implant produced according to the method of claim 5.

18. The implant according to claim 17, wherein the implant is formed as a CMF implant for reconstruction of a cartilage and/or bone component for a human body

19. An implant produced according to the method of claim 6.

20. An implant produced according to the method of claim 7.

21. The implant according to claim 20, wherein the implant is formed as a CMF implant for reconstruction of a cartilage and/or bone component for a human body

Description

[0025] In the present invention, three-dimensional implants are produced by means of selective laser sintering (SLS) out of UHMWPE, HDPE and/or PP. Herein, with defined energy input, the UHMWPE and/or HDPE and/or PP powder particles are fused together locally defined. All three components, only two or only one single component then is/are fused together/in itself (in pure form or in a mixture). By means of the fusing layer by layer according to the invention and subsequent solidifying a three-dimensional implant is formed by superimposing or interconnecting plural individual layers.

[0026] Hence short-term production of the implants and adaptation of the implants to the respective/intended/desired anatomic region can be guaranteed.

[0027] A production of massive and/or porous, geometrically complex, for example patient-specific, individual implants, but also of standard implants, by means of SLS technology becomes possible.

[0028] In particular quick adaptations to individual patients are enabled, especially in situ, ergo at the place of operation.

[0029] An increase in strength is achieved by a subsequent heat treatment. A surface treatment is beneficial to the ingrowing behavior, especially when a plasma treatment or a CO2-based technology is employed. The option of subsequent intra-operative modification by heat treatment is provided.

[0030] Possible realization of mechanical connecting functions shall be mentioned. For example, a combination with other materials such as synthetic materials, e.g. resorbable synthetic materials, may be implemented. An interconnection/joining, for example in the form of a bridge to another material or in the form of a bridge of a different material can be reasonably realized.

[0031] The possibility of integrating fixing options in combination with implant geometries is facilitated.

[0032] Laser-sintered porous implants having a total porosity between about 5% and about 90%, based on the empty volume relative to the total volume, are preferred by the users and can be produced by the presented method. Even a total porosity of more than 60% can be easily realized.

[0033] It is desired when the pore size is between about 100 m and about 3,500 m, especially about 80 m to about 120 m, preferably amounts to about 100 m.

[0034] It is also possible that all layers of the implant can be manufactured of UHMWPE and/or HDPE and/or PP.

[0035] All layers may be in the form of porous layers. It has turned to be advantageous when the porous laser-sintered implant is used in a defined anatomic region. There may also be obtained an interconnecting pore structure. Well-targeted roughening of the surface to about 5 m up to about 900 m is imaginable. The porous laser-sintered implant contains no more residual powder particles prior to use, however. The heat treatment is carried out so that no sealing of the pores will take place. An increase in strength between the interconnecting pore strands is obtained. Surface treatment by means of hot air, infrared emitters and/or thermal deburring and/or explosion deburring will take place. This is resulting in fusing/sealing without any pore sealing. At the same time, oxygen and fuel as well as an optional additive may be ignited at about 3,000 C.

[0036] Alternatively, also heat treatment using hot air is feasible. In this context, the use of a hot-air stream at a temperature of from 300 C. to 650 C. proves itself. The temperature on the implant is lower during the treatment, however. The distance observed should be about 10 cm to 30 cm. The heat treatment is carried out for about 5 seconds up to 60 seconds. In doing so, a reduction nozzle having a diameter of 14 mm to 9 mm, or a slot nozzle of 50 mm by 2 mm to 5 mm and, resp., 75 mm by 2 mm to 5 mm, or a flat die is used.

[0037] It is of advantage when the implant is hydrophobic and/or hydrophilic. For example, one side may be hydrophobic and the other side may be hydrophilic. The basic material may be hydrophobic, for example. In treatments with low-pressure plasma an optimum structure is obtained. The coating may be applied, for example, in such manner that hydrophilic behavior is provided in a particular area, e.g. only on one side. This helps to achieve quicker ingrowth from this side. The implant may be treated with low-pressure plasma.

[0038] Therefore, when the implant basically shows the one, e.g. hydrophobic, property, the other property, for example the hydrophilic property, can be caused by means of a coating. This is also possible vice versa.

[0039] Said particles of the group consisting of UHMWPE, HDPE and/or PP can also be used exclusively and/or at least significantly/predominantly. Mixtures exclusively therefrom are especially possible.