Biomaterial and bone implant for bone repair and replacement

• US 6,302,913 B1
• Filed: 11/22/1996
• Issued: 10/16/2001
• Est. Priority Date: 05/24/1994
• Status: Expired due to Fees

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.), Technology Finance Corporation (Proprietary) Limited,
• Original Assignee: Implico BV
• Inventors: Ripamonti, Ugo, Kirkbride, Anthony Nigel
• Primary Examiner(s): Milano, Michael J.
• Assistant Examiner(s): Koh, Choon P.
• Application Number:
  US08/737,760
• Time in Patent Office: 1,789 Days
• Field of Search: 623/16, 623/18, 623/66
• US Class Current: 623/16.11
• CPC Class Codes: A61C 8/0012 characterised by the material or composition, e.g. ceramics, surface layer, metal alloy use of specific materials A61K6/00
• CPC Class Codes: A61C 8/0013 with a surface layer, coating
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/2875 Skull or cranium A61F2/2803 and A61F2/3099 take precedence
• CPC Class Codes: A61F 2/30749 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30795 Blind bores, e.g. of circular cross-section
• 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 2220/0008 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2230/0069 cylindrical
• CPC Class Codes: A61F 2310/00023 Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00293 containing a phosphorus-containing compound, e.g. apatite
• CPC Class Codes: A61F 2310/00796 Coating or prosthesis-covering structure made of a phosphorus-containing compound, e.g. hydroxy(l)apatite
• CPC Class Codes: A61L 2430/02 for reconstruction of bones; weight-bearing implants
• CPC Class Codes: A61L 27/12 Phosphorus-containing materials, e.g. apatite

Abstract

This invention relates to a biomaterial useful in bone repair and replacement, and to implants for cranofacial, orthopaedic, and especially dental applications. The implants have a unique geometric configuration, their surfaces defining concavities having a shape and dimensions which induce or enhance the rate and/or amount of bone growth at the implant site. The biomaterial preferably has a specific porous configuration and the implant may be at least coated with such a biomaterial of hydroxyapatite, for example.

Claims

1. A bone implant for implanting into a subject at a site where bone growth is required, the implant comprising a body of sintered bioactive ceramic biomaterial, the body having intrinsic osteoinductive activity and having a network of interconnected coalesced rounded inner porous spaces as well as surface concavities of the body interconnected with the porous spaces, wherein the rounded inner porous spaces consist essentially of substantially spherical or spheroidal shaped spaces having diameter of between 300 μ

m and 3000 μ

m.

2. A bone implant according to claim 1, wherein the surface concavities consist essentially of concavities having a diameter of about 200 μ

m to 3000 μ

m, and a depth of 200 μ

m to 3000 μ

m, thereby enhancing the intrinsic osteoinductive activity of the body.

3. A bone implant according to claim 1, wherein the biomaterial is sintered hydroxyapatite, and has native or recombinant human bone morphogenetic proteins adsorbed therein.

4. A bone implant according to claim 1, wherein the outer surface of the body has been treated with a liquid etchant.

5. A method of inducing or enhancing the rate and/or amount of bone growth in a subject, in a site where bone growth is desired, which method includes:

selecting a bone implant according to claim 1, and having an appropriate overall shape and size for accommodation in the site; and

placing the implant into the subject in the site where bone growth is desired.

6. A bone implant according to claim 1, wherein the biomaterial has native or recombinant bone morphogenic proteins adsorbed therein.

7. A bone implant according to claim 1, wherein the biomaterial is sintered hydroxyapatite.