POROUS IMPLANT STRUCTURES
Porous biocompatible structures suitable for use as medical implants and methods for fabricating such structures are disclosed. The disclosed structures may be fabricated using rapid manufacturing techniques. The disclosed porous structures has a plurality of struts and nodes where no more than two struts intersect one another to form a node. Further, the nodes can be straight, curved, portions that are curved and/or straight. The struts and nodes can form cells which can be fused or sintered to at least one other cell to form a continuous reticulated structure for improved strength while providing the porosity needed for tissue and cell in-growth.
1 . A porous structure comprising:
a plurality of struts, each strut comprises:
a first end;
a second end; and
a continuous elongated body between said first and second ends, said body having a thickness and a length; and
a plurality of nodes, each node comprises an intersection between one end of a first strut and the body of a second strut;
wherein said porous structure is produced at least by a rapid manufacturing technologies process.
2 . The porous structure of claim 1 wherein the first and second ends of one or more struts extend between the body of two other struts.
3 . The porous structure of claim 1 , wherein the body of one or more struts comprise a plurality of nodes.
4 . The porous structure of claim 1 , wherein the cross-section of at least one end of one or more struts is larger than the cross-section of a portion of the body of said one or more struts.
5 . The porous structure of claim 1 wherein at least a portion of the body of one or more struts is curved.
6 . The porous structure of claim 1 wherein the plurality of struts can be sintered, melted, welded, bonded, fused, or otherwise connected to one another.
7 . The porous structure of claim 1 wherein a plurality of the struts and nodes define at least one fenestration.
8 . The porous structure of claim 1 further comprising material selected from the group consisting of metal, ceramic, metal-ceramic (cermet), glass, glass-ceramic, polymer, composite and combinations thereof.
9 . The porous structure of claim 8 wherein the metallic material is selected from the group consisting of titanium, titanium alloy, zirconium, zirconium alloy, niobium, niobium alloy, tantalum, tantalum alloy, nickel-chromium (e.g., stainless steel), cobalt-chromium alloy and combinations thereof.
10 . The porous structure of claim 1 wherein the cross section of one or more struts comprises a polygon.
11 . The porous structure of claim 1 wherein at least a portion of the circumference of the cross-section is curved.
12 . A method for fabricating a porous structure comprising the steps of:
creating a model of a porous structure at least in a computer generated environment, wherein the creation step comprises:
defining one or more struts with a first end, a second end, and a continuous elongated body between the first and second ends for each strut, selecting a thickness and length for the body; and
defining at least one node with an intersection between one end of a first strut and the body of a second strut for each node; and
fabricating the porous structure according to the model by exposing fusible material to an energy source.
13 . The method of claim 12 , further comprises the step of defining the first and second ends of one or more struts to extend between the body of two other struts.
14 . The method of claim 12 further comprises the step of defining the body of one or more struts to comprise a plurality of nodes.
15 . The method of claim 12 further comprises the step of defining the cross-section of at least one end of one or more struts to be larger than the cross-section of a portion of the body of said one or more struts.
16 . The method of claim 12 further comprises the step of defining at least a portion of the body of one or more struts to be curved.
17 . The method of claim 12 further comprises the step of sintering, melting, welding, bonding, or fusing a plurality of struts to one another.
18 . The method of claim 12 further comprises the step of defining at least one fenestration in the porous structure using a plurality of the struts and nodes.
19 . The method of claim 12 wherein the fabricating step further comprises selecting a material for fabricating the one or more struts from the group consisting of metal, ceramic, metal-ceramic (cermet), glass, glass-ceramic, polymer, composite and combinations thereof.
20 . The method of claim 19 further comprises selecting a metallic material from the group consisting of titanium, titanium alloy, zirconium, zirconium alloy, niobium, niobium alloy, tantalum, tantalum alloy, nickel-chromium (e.g., stainless steel), cobalt-chromium alloy and combinations thereof.
21 . The method of claim 12 further comprises the step of defining the cross section of one or more struts with a polygon.
22 . The method of claim 12 further comprises the step of defining at least a portion the circumference of the cross-section with a curved portion.
23 . A porous structure comprising:
at least one cell comprising:
a plurality of sides, each side comprising a polygon, wherein each leg of the polygon comprises a strut; wherein the strut comprises:
a first end;
a second end; and
a continuous elongated body between said first and second ends, said body having a thickness and a length; and
a plurality of nodes, each node comprises an intersection between one end of a first strut and the body of a second strut.
24 . The porous structure of claim 23 further comprising:
a plurality of cells coupled to one another in a stacked pattern wherein at least two cells share one side.
25 . The porous structure of claim 24 wherein said cell comprises a hollow interior.
26 . The porous structure of claim 23 wherein said porous structure is manufactured with rapid manufacturing technologies.