Implant forming method

• US 6,733,528 B2
• Filed: 08/06/2002
• Issued: 05/11/2004
• Est. Priority Date: 08/09/2001
• Status: Expired due to Fees

• Current Assignee: Pentax Corporation (Hoya Corporation), Ichiro Ono
• Original Assignee: Pentax Corporation (Hoya Corporation), Ichiro Ono
• Inventors: Ono, Ichiro, Abe, Keita, Nakasu, Masanori
• Primary Examiner(s): Lechert, Jr., Stephen J.
• Application Number:
  US10/212,151
• Publication Number:
  US 20030030170A1
• Time in Patent Office: 644 Days
• Field of Search: 264/113, 264/122, 264/123, 264/308, 623/11.11
• US Class Current: 623/11.11
• CPC Class Codes: A61L 27/12 Phosphorus-containing materials, e.g. apatite
• CPC Class Codes: B29C 64/165 using a combination of solid and fluid materials, e.g. a powder selectively bound by a liquid binder, catalyst, inhibitor or energy absorber

Abstract

A method for forming an implant having a desired shape includes the steps of (a) forming a layer of ingredient powder having a predetermined thickness composed of an ingredient powder, and (b) applying an reactant liquid to the layer in accordance with the desired shape of the implant, portions of the ingredient powder reacting with the reactant liquid being hardened. The above steps are repeated to stack a plurality of the layers having hardened portions, respectively, to form a three-dimensional implant formed by a stack of the hardened portions of the layers of the ingredient powder. The ingredient powder is a powder including at least one of a-tricalcium phosphate and tetracalcium phosphate, and a Ca/P ratio of the powder is within a range of 1.40 through 2.0.

Claims

1. A method for forming an implant having a desired shape, comprising:

(a) forming a layer of ingredient powder having a predetermined thickness composed of an ingredient powder; and

(b) applying a reactant liquid to the layer in accordance with the desired shape of the implant, portions of the ingredient powder reacting with the reactant liquid being hardened,

wherein the forming and the applying are repeated to stack a plurality of the layers having hardened portions, respectively, to form an implant formed by a stack of the hardened portions of the layers of the ingredient powder,

wherein the ingredient powder is a powder including at least one of a-tricalcium phosphate and tetracalcium phosphate, and

wherein a Ca/P ratio of the powder is within a range of 1.40 through 2.0.

2. The method according to claim 1,

wherein the ingredient powder is a powder containing a-tricalcium phosphate, tetracalcium phosphate and calcium hydrogen phosphate, and

wherein the Ca/P ratio of the ingredient powder is within a range of 1.40 through 1.80.

3. The method according to claim 1, wherein the hardening does not add a binder.

4. The method according to claim 1, further comprising removing the unhardened ingredient powder after the forming and the hardening have been finished.

5. The method according to claim 1, wherein the reactant liquid is at least mainly composed of water.

6. The method according to claim 1, wherein the ingredient powder generates apatite when the ingredient powder reacts with said reaction liquid.

7. The method according to claim 1, wherein the mean particle size of said ingredient powder is within a range of 5 μ

m through 40 μ

m.

8. The method according to claim 1, wherein the mean thickness of the layer of the ingredient powder is within a range of 0.1 mm through 0.5 mm.

9. The method according to claim 1, wherein the reaction liquid is blown to the layer of ingredient powder in a form of drops.

10. The method according to claim 1, wherein porosity of the implant which is formed in accordance with the method is within a range of 10 through 90 vol %.

11. An implant formed in accordance with an implant forming method that includes:

(a) forming a layer of ingredient powder having a predetermined thickness composed of an ingredient powder; and

(b) applying a reactant liquid to the layer in accordance with the desired shape of the implant, portions of the ingredient powder reacting with the reactant liquid being hardened,

wherein the forming and the applying are repeated to stack a plurality of the layers having hardened portions, respectively, to form an implant formed by a stack of the hardened portions of the layers of the ingredient powder,

wherein the ingredient powder is a powder including at least one of a-tricalcium phosphate and tetracalcium phosphate, and

wherein a Ca/P ratio of the powder is within a range of 1.40 through 2.0.

12. A method for forming an implant having a desired shape, comprising the steps of:

(a) forming a layer of ingredient powder having a predetermined thickness composed of an ingredient powder; and

(b) applying an reactant liquid to the layer in accordance with a cross-sectional shape of the implant corresponding to a currently processed layer, portions of the ingredient powder reacting with the reactant liquid being hardened,

wherein the forming and the applying are repeated with shifting a level of the layer so as to stack a plurality of the layers having hardened portions are formed one by one to form an implant formed by a stack of the hardened portions of the layers of the ingredient powder,

wherein the ingredient powder is a powder including at least one of a-tricalcium phosphate and tetracalcium phosphate, and

wherein a Ca/P ratio of the powder is within a range of 1.40 through 2.0.