Porous ceramic body

• US 20020037799A1
• Filed: 12/15/2000
• Published: 03/28/2002
• Est. Priority Date: 12/16/1999
• Status: Active Grant

• Current Assignee: Octoplus Sciences B.V.
• Original Assignee: Isotis N.V.
• Inventors: Li, Shihong, Layrolle, Pierre Jean F., de Wijn, Joost Robert, de Groot, Klaas, van Blitterswijk, Clemens Antoni
• Granted Patent: US 6,479,418 B2
• Time in Patent Office: Days
• US Class Current: 501/82
• CPC Class Codes: A61L 2400/18 Modification of implant surfaces in order to improve biocompatibility, cell growth, fixation of biomolecules, e.g. plasma treatment
• CPC Class Codes: A61L 27/12 Phosphorus-containing materials, e.g. apatite
• CPC Class Codes: C04B 38/009 Porous or hollow ceramic granular materials, e.g. microballoons C04B18/027, C04B20/002 take precedence
• CPC Class Codes: C04B 38/0615 the burned-out substance being a monolitic element having approximately the same dimensions as the final article, e.g. a porous polyurethane sheet or a prepreg obtained by bonding together resin particles C04B38/0022 takes precedence
• CPC Class Codes: C04B 38/062 the burned-out substance being formed in situ, e.g. by polymerisation of a prepolymer composition containing ceramic powder

Abstract

The invention relates to a process for preparing a porous ceramic body, which process is based on a negative replica method. The invention further relates to a ceramic body obtainable by said method and to its use as a scaffold for tissue engineering.

Claims

1. A process for preparing a porous ceramic body comprising the steps of:

1) preparing an aqueous slurry of a ceramic material;

2) mixing the slurry with a liquid, viscous organic phase to obtain a dough, wherein the organic phase is substantially insoluble in water, and is thermally decomposable into gaseous residues;

3) drying the dough; and

4) removing the organic phase by thermal decomposition.

2. A process according to claim 1, wherein the ceramic material is a calcium phosphate.

3. A process according to claim 2, wherein the calcium phosphate is selected from the group consisting of octacalcium phosphate, apatites, such as hydroxyapatite and carbonate apatite, whitlockites, α

-tricalcium phosphate, β

-tricalcium phosphate, and sodium calcium phosphate, and combinations thereof.

4. A process according to claim 1, wherein the slurry comprises between 50 and 80 wt. % of ceramic material, based on the weight of the slurry.

5. A process according to claim 1, wherein the organic phase comprises a material selected from the group consisting of waxes, shellac, fatty acids, fats, epoxy resins, polyurethane resins, polyester resins, and poly(meth)acrylate resins, and combinations thereof.

6. A process according to claim 5, wherein the organic phase comprises a poly(meth)acrylate resin.

7. A process according to claim 1, wherein the organic phase solidifies upon drying.

8. A process according to claim 6, wherein the organic phase comprises polymethylmathacrylate, methylmethacrylate and a polymerizing initiator.

9. A process according to claim 1, wherein the dough is dried for at least 5 hours under atmospheric conditions.

10. A process according to claim 1, wherein the organic phase is removed at a temperature of between 200 and 800°

C.

11. A porous ceramic body obtainable by a process according to claim 1.

12. A porous ceramic body according to claim 11, having interconnected pores of a mean size between about 400 and about 4000 μ

m, a porosity of at least 40%, and a compressive strength of at least 10 MPa.

13. The use of a porous ceramic body according to claim 11 as a scaffold in tissue engineering.

14. A process according to claim 1, wherein the porous ceramic body is sintered at a temperature of between about 800 and about 1400°

c.

15. A porous ceramic body obtainable by a process according to claim 14.

16. A porous ceramic body according to claim 15 having interconnected pores of a mean size between about 400 and about 4000 μ

m, a porosity of at least 40%, and a compressive strength of at least 10 MPa.

17. The use of a porous ceramic body according to claim 15 as a scaffold in tissue engineering.

18. A process for preparing a porous ceramic granulate comprising crushing a porous ceramic body according to claim 11.

19. A porous ceramic granulate obtainable by a process according to claim 18 having a mean particle diameter of between about 2 and about 3.5 mm.