Bone-graft material and method of manufacture

• US 4,781,721 A
• Filed: 05/19/1986
• Issued: 11/01/1988
• Est. Priority Date: 02/25/1981
• Status: Expired due to Term

• Current Assignee: S + G Implants GmbH
• Original Assignee: S+G Implants
• Inventors: Grundei, Hans
• Primary Examiner(s): Apley, Richard J.
• Assistant Examiner(s): Isabella, David J.
• Application Number:
  US06/864,571
• Time in Patent Office: 897 Days
• Field of Search: 623/11, 623/16, 623/19, 623/20, 623/21, 623/22, 623/23, 623/24, 164/34, 164/35, 164/36, 264/44
• US Class Current: 164/34
• CPC Class Codes: A61B 17/68 Internal fixation devices , including fasteners and spinal fixators, even if a part thereof projects from the skin bone staples A61B17/0642
• CPC Class Codes: A61B 17/80 Cortical plates , i.e. bone plates; Instruments for holding or positioning cortical plates, or for compressing bones attached to cortical plates
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/30734 Modular inserts, sleeves or augments, e.g. placed on proximal part of stem for fixation purposes or wedges for bridging a bone defect
• CPC Class Codes: A61F 2/30907 Nets or sleeves applied to surface of prostheses or in cement
• CPC Class Codes: A61F 2/36 Femoral heads ; Femoral endoprostheses
• CPC Class Codes: A61F 2/3662 Femoral shafts
• CPC Class Codes: A61F 2002/2825 Femur
• CPC Class Codes: A61F 2002/2835 Bone graft implants for filling a bony defect or an endoprosthesis cavity, e.g. by synthetic material or biological material
• CPC Class Codes: A61F 2002/2892 Tibia
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30266 wedge-shaped parallelepipeds
• CPC Class Codes: A61F 2002/30736 Augments or augmentation pieces, e.g. wedges or blocks for bridging a bone defect
• CPC Class Codes: A61F 2002/30738 Sleeves
• CPC Class Codes: A61F 2002/30919 Sleeves
• CPC Class Codes: A61F 2002/3092 having an open-celled or open-pored structure
• CPC Class Codes: A61F 2002/30957 using a positive or a negative model, e.g. moulds
• CPC Class Codes: A61F 2002/3631 with an integral complete or partial peripheral collar or bearing shoulder at its base
• CPC Class Codes: A61F 2230/0069 cylindrical
• CPC Class Codes: A61F 2230/0082 parallelepipedal
• CPC Class Codes: A61F 2310/00011 : Metals or alloys
• CPC Class Codes: A61F 2310/00179 : Ceramics or ceramic-like structures
• CPC Class Codes: A61L 2430/02 : for reconstruction of bones; weight-bearing implants
• CPC Class Codes: A61L 27/56 : Porous materials, e.g. foams or sponges
• CPC Class Codes: Y10S 623/901 : Method of manufacturing prosthetic device

Abstract

This invention relates to bone-graft material or implant and to the method of producing the same, for the replacement of animal and human bones and bone parts. The material or implant comprises a morphologically stable, open-pored or open-celled moulding having a sponge-like structure. The mean width of the pores or cells in the implant is in the range of 0.5 to 1.5 mms. and preferably of 0.8 to 1.0 mm. The implant may be made of metal or plastic material, and may be of any desired shape, such as a wedge, a key, a parallelepiped, a cylinder, a disc or a sheath, for example.

Claims

1. A method for manufacturing a morphologically stable implant for replacement of animal or human bone, which implant comprises an open-pored or open-celled porous sponge-like structure of metal having pores or cells of a mean width in the range of 0.5-1.5 mm, method comprising using an open-pored or open-celled sponge as a positive molding pattern for the implant, the sponge pores or cells having a mean width in the range of 0.5-1.5 mm, filling the pores or cells of the sponge with a heat resistant orthodonically embedding material, applying heat to the sponge filled with said embedding material so as to remove the sponge by vaporizing thereof, and wherein said embedding material remains to form a core having cavities or openings corresponding to the sponge, filling the cavities or openings of said core with a metal by casting, and removing said core so as to obtain a metal implant having a sponge-like structure provided with pores or cells corresponding to the pores or cells of the sponge, and having a mean width of 0.5-1.5 mm.

2. A method according to claim 1, for manufacturing a morphologically stable implant, which implant comprises an open-pored, open-celled porous sponge-like structure of a plastic material, wherein the cavities or openings of said core are filled with a plastic material by centrifuging, so as to obtain an implant of plastic material having a sponge-like structure provided with pores or cells corresponding to the pores or cells of the sponge.