Implantable ceramic bone prosthesis

• US 3,905,047 A
• Filed: 06/27/1973
• Issued: 09/16/1975
• Est. Priority Date: 06/27/1973
• Status: Expired due to Term

• Current Assignee: Roger A. Long
• Original Assignee: Roger A. Long
• Inventors: Long, Roger A.
• Primary Examiner(s): Frinks, Ronald L.
• Application Number:
  US05/373,959
• Time in Patent Office: 811 Days
• Field of Search: 3/1,1.9-1.913 128/92C,92CA,92R,92G 32/1A 106/39.5,55
• US Class Current: 623/23.56
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2310/00203 containing alumina or aluminium oxide
• CPC Class Codes: A61L 27/425 of phosphorus containing material, e.g. apatite

Abstract

The improved bone prosthesis of the invention comprises a unitary body containing an eutectic of metal pyrophosphate and refractory oxide. Preferably, the body also contains discrete particles of refractory oxide bonded together by the eutectic which serves as a matrix bonder. Moreover, the particles are preferably of the same refractory oxide, such as alumina, as is present in the eutectic and are of extended surface area for improved strength. The pyrophosphate preferably is calcium pyrophosphate so that the prosthesis is biodegradable. The prosthesis can be prepared, in accordance with the present method, by forming the eutectic, preferably a pourable mixture of the particles and the molten eutectic, and pouring the mixture into and filling a mold of a bone to be duplicated, solidifying the mold and recovering it from the mold. The surface of the prosthesis can be texturized, as by acid etching it, to increase bond ingrowth and/or tissue attachment when implanted.

Claims

1. AN IMPROVED IMPLANTABLE BONE PROSTHESIS, SAID PROSTHESIS COMPRISING A UNITARY CERAMIC BODY CONTAINING A EUTHECTIC OF METAL PYROPHOSPHATE AND REFRACTORY OXIDE, WHEREIN SAID BODY INCLUDES DESCRETE PARTICLES OF REFRACTORY OXIDE BONDED TOGETHER BY SAID EUTHECTIC, WHEREBY SAID EUTHECTIC BONDS TOGETHER THE DISCRETE PARTICLES OF REFRACTORY OXIDE IN SUCH A MANNER THAT NO SUBSTANTIAL DEGRADATION OF SAID DISCRETE PARTICLES BY THE EUTECTIC OCCURS.

2. The improved bone prothesis of claim 1 wherein said particles are in the form of fibers.

3. The improved bone prosthesis of claim 1 wherein said particles are in the form of flakes.

4. The improved bone prosthesis of claim 1 wherein said refractory oxide comprises refractory metal oxide.

5. The improved bone prosthesis of claim 1 wherein said particles are of the same refractory oxide as that of said eutectic.

6. The improved bone prosthesis of claim 1 wherein said metal pyrophosphate comprises calcium pyrophosphate, whereby said prosthesis is biodegradable.

7. The improved bone prosthesis of claim 4 wherein the refractory oxide in said eutectic comprises alumina.

8. The improved bone prosthesis of claim 4 wherein said particles comprise alumina.

9. The improved bone prosthesis of claim 6 wherein said eutectic consists essentially of calcium pyrophosphate and alumina and wherein said particles consist essentially of alumina.

10. The improved bone prosthesis of claim 9 wherein said particles are of extended surface area for improved structural strength, and wherein said eutectic is present in a concentration in excess of about 80 percent, by weight, of said prosthesis.