Prosthetic articles and methods for producing same

• US 5,728,510 A
• Filed: 10/13/1995
• Issued: 03/17/1998
• Est. Priority Date: 01/30/1991
• Status: Expired due to Fees

• Current Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Interpore International Inc. (Zimmer Biomet Holdings, Inc.)
• Inventors: White, Eugene W.
• Primary Examiner(s): Lesmes, George F.
• Assistant Examiner(s): Codd, Bernard P.
• Application Number:
  US08/542,846
• Time in Patent Office: 886 Days
• Field of Search: 430/269, 430/320, 430/323, 430/326, 264/161, 264/219, 216/56, 216/100, 219/69.17
• US Class Current: 430/323
• CPC Class Codes: A61F 2/0077 Special surfaces of prostheses, e.g. for improving ingrowth A61F2/30767 takes precedence
• CPC Class Codes: A61F 2/06 Blood vessels
• CPC Class Codes: A61F 2/105 Skin implants, e.g. artificial skin
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/30771 applied in original prostheses, e.g. holes or grooves
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2002/30153 rectangular
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30261 parallelepipedal
• CPC Class Codes: A61F 2002/30263 cubical
• CPC Class Codes: A61F 2002/30298 Parallelepipedal body made by spirally rolling up a sheet or a strip around itself
• CPC Class Codes: A61F 2002/30303 polypod-shaped
• CPC Class Codes: A61F 2002/30448 using adhesives
• CPC Class Codes: A61F 2002/30599 stackable
• CPC Class Codes: A61F 2002/30785 parallel
• CPC Class Codes: A61F 2002/308 oblong
• CPC Class Codes: A61F 2002/30808 parallel
• CPC Class Codes: A61F 2002/30838 Microstructures
• CPC Class Codes: A61F 2002/30892 parallel
• CPC Class Codes: A61F 2002/30896 perpendicular with respect to each other
• CPC Class Codes: A61F 2002/3092 : having an open-celled or open-pored structure
• CPC Class Codes: A61F 2002/30929 : having at least two superposed coatings
• CPC Class Codes: A61F 2002/30957 : using a positive or a negative model, e.g. moulds
• CPC Class Codes: A61F 2002/30968 : Sintering
• CPC Class Codes: A61F 2002/30978 : using electrical discharge machining [EDM]
• CPC Class Codes: A61F 2220/005 : using adhesives
• CPC Class Codes: A61F 2230/0019 : rectangular
• CPC Class Codes: A61F 2230/0063 : Three-dimensional shapes
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2230/0082 : parallelepipedal
• CPC Class Codes: A61F 2230/0084 : cubical
• CPC Class Codes: A61F 2230/0091 : helically-coiled or spirally-coiled, i.e. having a 2-D spiral cross-section
• CPC Class Codes: A61F 2250/0063 : Nested prosthetic parts
• CPC Class Codes: A61F 2310/00293 : containing a phosphorus-containing compound, e.g. apatite
• CPC Class Codes: A61F 2310/00365 : Proteins; Polypeptides; Degradation products thereof
• CPC Class Codes: A61F 2310/00383 : Gelatin
• CPC Class Codes: A61L 27/56 : Porous materials, e.g. foams or sponges
• CPC Class Codes: B29C 39/148 : characterised by the shape of the surface
• CPC Class Codes: B29D 28/00 : Producing nets or the like, e.g. meshes, latticesby knotting D04G
• CPC Class Codes: B29L 2031/737 : Articles provided with holes, e.g. grids, sieves nets B29L2028/00
• CPC Class Codes: D04H 1/70 : characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
• CPC Class Codes: Y10T 428/24273 : including aperture
• CPC Class Codes: Y10T 428/24298 : Noncircular aperture [e.g., slit, diamond, rectangular, etc.]
• CPC Class Codes: Y10T 428/24322 : Composite web or sheet
• CPC Class Codes: Y10T 428/24479 : including variation in thickness
• CPC Class Codes: Y10T 428/24562 : Interlaminar spaces
• CPC Class Codes: Y10T 428/24661 : Forming, or cooperating to form cells
• CPC Class Codes: Y10T 428/2495 : Thickness [relative or absolute]
• CPC Class Codes: Y10T 428/249953 : Composite having voids in a component [e.g., porous, cellular, etc.]
• CPC Class Codes: Y10T 428/249975 : Void shape specified [e.g., crushed, flat, round, etc.]
• CPC Class Codes: Y10T 428/249978 : Voids specified as micro
• CPC Class Codes: Y10T 428/249991 : Synthetic resin or natural rubbers
• CPC Class Codes: Y10T 428/268 : Monolayer with structurally defined element

Abstract

A porous mesh structure is prepared in sheet form having a unique arrangement of main and secondary troughs on a first surface, and openings extending therethrough. The arrangement of troughs and openings creates an elaborate matrix of pores when the sheet is layer on itself in a front to back manner. This arrangement of pores and support structure emulates certain cortical bone structures and is therefore very effective as an artificial bone material. In addition, the porous structure has significant other potential uses outside the medical field and can be effectively applied accordingly, based on its fundamental. structural attributes.

Claims

1. A process for manufacturing a non-woven porous mesh comprising the steps of:

selecting a form having a flat shape and uniform thickness between a first and second side that is suitable for molding polymeric materials;

creating openings in and normal to said form extending therethrough wherein said openings have substantially similar effective diameters and are distributed across the sides of said form in a substantially uniform pattern;

creating plural troughs in the first side of said form whereby a trough, running parallel to the plane of the first side with a width corresponding to the effective diameter of said opening and depth approximately equal to one-half the effective diameter of said openings, is established between each pair of adjacent openings;

filling said form with a curable material in a fluid state;

curing said curable material;

deflashing said cured material; and

removing said cured material from said form.

2. The method of claim 1, wherein the steps of creating said openings and troughs further comprises the steps of:

preparing a mask defining the two dimensional location of said openings and troughs;

treating the surface of said form with a photosensitive material;

selectively exposing said form to electromagnetic energy filtered by said mask;

removing the exposed portions of said photosensitive material; and

chemically etching the exposed surface of said form.

3. The method of claim 1, wherein the steps of creating said openings and troughs comprises the selective machining of the form using electrical discharge.

4. The method of claim 1, wherein said openings have an effective diameter of 25 to 1000 μ

m.