Calcium phosphate bone graft material, process for making same and osteoimplant fabricated from same

Abstract

A calcium phosphate bone graft material comprising an amorphous calcium phosphate glassy phase of from about 30 to about 100 volume % is obtained by plasma spraying calcium phosphate-containing powder onto a target to produce a deposited layer and removing the deposited layer from the target to provide the calcium phosphate bone graft material.

What is claimed is:  
     
         1 . A calcium phosphate bone graft material comprising an amorphous calcium phosphate glassy phase representing from about 30 to about 100 volume % of the total volume of the calcium phosphate bone graft material, said material being obtained by plasma spraying calcium phosphate-containing powder onto a target to produce a deposited layer thereon and removing the deposited layer from the target to provide the calcium phosphate bone graft material.  
     
     
         2 . The bone graft material of    claim 1    possessing an average particle size of from about 50 to about 4000 microns.  
     
     
         3 . The bone graft material of    claim 1    wherein the calcium phosphate-containing powder comprises sintered or unsintered hydroxyapatite, sintered or unsintered tricalcium phosphate, and mixtures thereof.  
     
     
         4 . The bone graft material of    claim 1    wherein the calcium phosphate-containing powder further comprises calcium carbonate, calcium sulfate, or mixtures thereof.  
     
     
         5 . The bone graft material of    claim 1    wherein the calcium phosphate-containing powder comprises animal bone tissue which has been heat treated to remove the organic constituents thereof.  
     
     
         6 . An osteoimplant comprising the calcium phosphate bone graft material of    claim 1   .  
     
     
         7 . The osteoimplant of    claim 6    further comprising at least one bone-derived element.  
     
     
         8 . The osteoimplant of    claim 7    wherein the bone-derived element comprises demineralized bone particles.  
     
     
         9 . The osteoimplant of    claim 6    further comprising at least one biocompatible polymer.  
     
     
         10 . A method of making a calcium phosphate bone graft material which comprises 
 providing a calcium phosphate-containing powder;    plasma spraying the calcium phosphate-containing powder onto a target to provide a deposited layer thereon; and    removing the deposited layer to provide a calcium phosphate bone graft material wherein the amorphous phase represents from about 30 to about 100 volume % of the total volume of the calcium phosphate bone graft material.    
     
     
         11 . The method of    claim 10    wherein the target contains cavities.  
     
     
         12 . The method of    claim 10    wherein the average particle size of the calcium phosphate bone graft material is from about 50 to about 4000 microns.  
     
     
         13 . The method of    claim 10    which further comprises compressing the calcium phosphate bone graft material under pressure to form a solid aggregate.  
     
     
         14 . The method of    claim 13    wherein the calcium phosphate bone graft material comprises bone-derived elements in combination therewith.  
     
     
         15 . The method of    claim 13    wherein the calcium phosphate bone graft material comprises a biocompatible polymer in combination therewith.  
     
     
         16 . A method of treating a bone defect which comprises: 
 providing the calcium phosphate bone graft material of    claim 1   ; and    placing the calcium phosphate bone graft material inside the bone defect.