Viscous suspension spinning process for producing resorbable ceramic fibers and scaffolds

• US 6,451,059 B1
• Filed: 11/12/1999
• Issued: 09/17/2002
• Est. Priority Date: 11/12/1999
• Status: Expired due to Fees

• Current Assignee: Ethicon Incorporated (Johnson & Johnson)
• Original Assignee: Ethicon Incorporated (Johnson & Johnson)
• Inventors: TenHuisen, Kevor S., Janas, Victor F.
• Primary Examiner(s): Willse, David H.
• Assistant Examiner(s): STEWART, ALVIN J
• Application Number:
  US09/439,656
• Time in Patent Office: 1,040 Days
• Field of Search: 623/23.56, 623/23.51, 623/23.75, 623/23.76, 428/224, 427/2.27
• US Class Current: 623/23.51
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2002/2817 Bone stimulation by chemical reactions or by osteogenic or biological products for enhancing ossification, e.g. by bone morphogenetic or morphogenic proteins [BMP] or by transforming growth factors [TGF]
• 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 2002/30011 differing in porosity
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30199 Three-dimensional shapes
• CPC Class Codes: A61F 2002/3093 for promoting ingrowth of bone tissue
• CPC Class Codes: A61F 2002/30968 Sintering
• CPC Class Codes: A61F 2002/4648 Means for culturing bone graft
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2230/0063 Three-dimensional shapes
• CPC Class Codes: A61F 2250/0023 differing in porosity
• CPC Class Codes: A61F 2310/00293 containing a phosphorus-containing compound, e.g. apatite
• CPC Class Codes: A61F 2310/0097 Coating or prosthesis-covering structure made of pharmaceutical products, e.g. antibiotics
• CPC Class Codes: A61L 27/12 Phosphorus-containing materials, e.g. apatite
• CPC Class Codes: C03B 37/011 starting from a liquid phase reaction process, e.g. through a gel phase
• CPC Class Codes: C04B 14/46 Rock wool ; Ceramic or silicate fibres C04B14/40, C04B14/42 take precedence
• CPC Class Codes: C04B 2111/00836 for medical or dental applications
• CPC Class Codes: C04B 30/02 : containing fibrous materials
• CPC Class Codes: C04B 35/447 : based on phosphates , e.g. hydroxyapatite
• CPC Class Codes: C04B 35/62268 : Fibres based on metal phosphorus oxides, e.g. phosphates
• CPC Class Codes: C04B 38/06 : by burning-out added substances by burning natural expanding materials or by sublimating or melting out added substances
• CPC Class Codes: C04B 40/0268 : Heating up to sintering temperatures C04B41/0072 takes precedence
• CPC Class Codes: C04B 41/4582 : Porous coatings, e.g. coating containing porous fillers
• CPC Class Codes: C04B 41/48 : Macromolecular compounds

Abstract

The present invention provides a hard tissue scaffold comprising a resorbable ceramic. The scaffold is formed by first creating unfired (green) bioresorbable ceramic fibers via the viscous suspension spinning process (VSSP). Then, using common textile techniques, a structure in which the size and distribution of interconnected pores are controlled, is created. Heat treating the structure to remove the organic phase and sintering the ceramic yields a hard tissue scaffold.

Claims

1. A process for making a biocompatible ceramic implant device, comprising the following steps:

a) solution spinning a biocompatible calcium phosphate powder within an organic phase comprising a biocompatible organic polymer to create an unfired bioresorbable ceramic fiber;

b) processing the unfired bioresorbable ceramic fiber to form a three-dimensional structure in which size and distribution of interconnected pores are controlled; and

c) heat treating the structure to remove the organic phase and sinter the bioresorbable ceramic fiber, to yield biocompatible, resorbable hard tissue scaffolds comprising ceramic fibers cross-sintered with one another.

2. The process of claim 1 wherein the calcium phosphate is selected from the group consisting of hydroxyapatite, tricalcium phosphate, tetracalcium phosphate, and multi-phasic blends of resorbable glasses and ceramics .

3. The process of claim 1 wherein the biocompatible polymer is selected from the group consisting of synthetics, cellulosics, polyvinyl alcohols, polyesters, and combination thereof.

4. The process of claim 1 wherein the three-dimensional structure is formed by a textile process selected from the group consisting of weaving, knitting, and braiding.

5. The process of claim 1 wherein the ceramic surfaces of the scaffold are treated to promote bone growth through the scaffold.

6. The process of claim 1 wherein the interconnected pores of the scaffold are coated with materials which promote bone growth through the scaffold.

7. The process of claim 1 wherein the interconnected pores of the scaffold are filled with natural or synthetic materials which promote bone growth through the scaffold.

8. The process of claim 1 wherein the interconnected pores of the scaffold are filled with resorbable polymers which improve the mechanical properties of the scaffold.

9. The process of claim 1 wherein the interconnected pores of the scaffold are filled with resorbable polymers containing natural or synthetic materials which promote bone growth through the scaffold.

10. The process of claim 1 wherein the scaffold is filled with a porous open cell foam made from an absorbable polymer.

11. The process of claim 1 wherein cells are grown on the scaffold in vitro.

12. The scaffold of claim 1 wherein the scaffold is seeded with cells.

13. The process of claim 1 wherein the scaffold is seeded with cells.

14. A process for making a biocompatible bioresorbable ceramic implant device, formed by the following steps:

a) using a viscous suspension spinning process to spin a solution containing a biocompatible calcium phosphate powder dispersed in an organic phase containing a suitable organic polymer to create an unfired bioresorbable ceramic fiber;

b) using common textile techniques to form the bioresorbable unfired ceramic fiber into a three-dimensional structure in which size and distribution of interconnected pores are controlled; and

c) heat treating the structure to remove the organic phase and sinter the bioresorbable ceramic fiber, to yield a biocompatible, resorbable hard tissue scaffold comprising ceramic fibers cross-sintered with one another.

15. The process of claim 14 wherein the calcium phosphate is selected from the group consisting of hydroxyapatite, tricalcium phosphate, tetracalcium phosphate, and multi-phasic blends of resorbable glasses and ceramics.

16. The process of claim 14 wherein the biocompatible polymer is selected from the group consisting of synthetics, cellulosics, polyvinyl alcohols, polyesters, and combination thereof.

17. The process of claim 14 wherein the three-dimensional structure is formed by a textile process selected from the group consisting of weaving, knitting, and braiding.

18. The process of claim 14 wherein the ceramic surfaces of the scaffold are treated to promote bone growth through the scaffold.

19. The process of claim 14 wherein the interconnected pores of the scaffold are coated with materials which promote bone growth through the scaffold.

20. The process of claim 14 wherein the interconnected pores of the scaffold are filled with natural or synthetic materials which promote bone growth through the scaffold.

21. The process of claim 14 wherein the interconnected pores of the scaffold are filled with resorbable polymers which improve the mechanical properties of the scaffold.

22. The process of claim 14 wherein the interconnected pores of the scaffold are filled with resorbable polymers containing natural or synthetic materials which promote bone growth through the scaffold.

23. The process of claim 14 wherein the scaffold is filled with a porous open cell foam made from an absorbable polymer.

24. The process of claim 14 wherein cells are grown on the scaffold in vitro.