US2009149553A1PendingUtilityA1

Injectable resorbable bone graft material, powder for forming same and methods relating thereto for treating bone defects

56
Individually held — no corporate assignee on recordPriority: Feb 4, 2003Filed: Feb 17, 2009Published: Jun 11, 2009
Est. expiryFeb 4, 2023(expired)· nominal 20-yr term from priority
Inventors:Jantzen ColeMichael E. CarrollJon P. MoseleyKelly C. Richelsoph
A61F 2210/0004C04B 28/14A61B 2017/00004A61F 2002/30062A61L 2430/02C04B 2111/00146C04B 2111/00836A61L 27/58A61L 27/50A61L 27/10A61F 2002/2835
56
PatentIndex Score
0
Cited by
0
References
0
Claims

Abstract

An injectable resorbable bone graft material, and methods of using the same, provide increased compressive strength after injection in a bone defect. The bone graft material is made from calcium sulfate hemihydrate having a thick stubby rod-like crystalline structure and low water-carrying capacity.

Claims

exact text as granted — not AI-modified
1 . A method for treating bone defects comprising the steps of:
 mixing a powder comprising calcium sulfate hemihydrate with a diluent to produce a bone graft material in the form of a paste; and   applying the bone graft material to a bone defect, the bone graft material having a compressive strength in excess of 15 MPa within one hour after said applying step.   
   
   
       2 . The method of  claim 1 , wherein the bone graft material has a compressive strength of approximately 45-49 MPa within one hour after said applying step. 
   
   
       3 . The method of  claim 1 , wherein the bone graft material has a compressive strength exceeding approximately 50 MPa within one hour after said applying step. 
   
   
       4 . The method of  claim 1 , wherein the bone graft material has a compressive strength of at least 6 MPa within 20 minutes after said applying step. 
   
   
       5 . The method of  claim 1 , wherein the bone graft material has a compressive strength of at least 35 MPa within 24 hours after said injecting step. 
   
   
       6 . The method of  claim 5 , wherein the bone graft material has a compressive strength of approximately 56 MPa within 24 hours after said injecting step. 
   
   
       7 . The method of  claim 1 , wherein the diluent is water or a solution comprising an inorganic salt or a cationic surface active agent. 
   
   
       8 . The method of  claim 1 , wherein the calcium sulfate hemihydrate is formed by immersing calcium sulfate dihydrate in a solution of water and an inorganic salt to form a mixture, and heating the mixture to substantially its boiling point at atmospheric pressure such that the calcium sulfate dihydrate is converted to calcium sulfate hemihydrate. 
   
   
       9 . The method of  claim 1 , wherein the bone graft material has a working time of at least 5 minutes following mixing. 
   
   
       10 . The method of  claim 1 , wherein the bone graft material further comprises an accelerant. 
   
   
       11 . The method of  claim 10 , wherein the accelerant is selected from the group consisting of calcium sulfate dihydrate, calcium sulfate dihydrate coated with sucrose, potassium sulfate, and sodium sulfate. 
   
   
       12 . The method of  claim 1 , wherein the bone graft material further comprises one or more additives selected from the group consisting of bone marrow aspirate, platelet concentrate, blood, antibiotics, chemotherapeutic agents, growth factors, and analgesics. 
   
   
       13 . The method of  claim 1 , wherein the diluent to powder weight ratio is 0.19:1 to 0.31:1. 
   
   
       14 . The method of  claim 1 , wherein the powder comprises between about 99.8 to 100 percent by weight calcium sulfate hemihydrate. 
   
   
       15 . The method of  claim 1 , wherein the calcium sulfate hemihydrate consists of thick, stubby, rod-like crystals having a low water carrying capacity. 
   
   
       16 . The method of  claim 1 , wherein the applying step comprises injecting the paste into a bone defect. 
   
   
       17 . A method for preparing a bone graft material for treating bone defects comprising the step of mixing a powder comprising calcium sulfate hemihydrate with a diluent to produce a bone graft material in the form of a paste, wherein when undergoing dry-testing, the bone graft material has a compressive strength of approximately 88 MPa within 24 hours after said mixing step. 
   
   
       18 . The method of  claim 17 , wherein the bone graft material has a compressive strength exceeding approximately 106 MPa within 24 hours after said mixing step. 
   
   
       19 . The method of  claim 17 , wherein the diluent is water or a solution comprising an inorganic salt or a cationic surface active agent. 
   
   
       20 . The method of  claim 17 , wherein the calcium sulfate hemihydrate is formed by immersing calcium sulfate dihydrate in a solution of water and an inorganic salt to form a mixture, and heating the mixture to substantially its boiling point at atmospheric pressure such that the calcium sulfate dihydrate is converted to calcium sulfate hemihydrate. 
   
   
       21 . The method of  claim 17 , wherein the bone graft material has a working time of at least 5 minutes following mixing. 
   
   
       22 . The method of  claim 17 , wherein the bone graft material further comprises an accelerant. 
   
   
       23 . The method of  claim 22 , wherein the accelerant is selected from the group consisting of calcium sulfate dihydrate, calcium sulfate dihydrate coated with sucrose, potassium sulfate, and sodium sulfate. 
   
   
       24 . The method of  claim 17 , wherein the diluent to powder weight ratio is 0.19:1 to 0.31:1. 
   
   
       25 . The method of  claim 17 , wherein the powder comprises between about 99.8 to 100 percent by weight calcium sulfate hemihydrate. 
   
   
       26 . The method of  claim 17 , wherein the calcium sulfate hemihydrate consists of thick, stubby, rod-like crystals having a low water carrying capacity. 
   
   
       27 . A method for preparing a bone graft material for treating bone defects comprising the steps of:
 providing a bone graft material composition comprising a powder component and a diluent, wherein the powder component comprises calcium sulfate hemihydrate prepared by immersing calcium sulfate dihydrate in a solution of water and an inorganic salt to form a mixture, and heating the mixture to substantially its boiling point at atmospheric pressure such that the calcium sulfate dihydrate is converted to calcium sulfate hemihydrate; and   mixing the powder component with the diluent to produce a bone graft material in the form of a paste.   
   
   
       28 . The method of  claim 27 , wherein the calcium sulfate hemihydrate consists of thick, stubby, rod-like crystals having a low water carrying capacity. 
   
   
       29 . The method of  claim 27 , wherein the powder component comprises between about 99.8 to 100 percent by weight calcium sulfate hemihydrate. 
   
   
       30 . The method of  claim 27 , wherein the diluent to powder weight ratio is 0.19:1 to 0.31:1. 
   
   
       31 . The method of  claim 27 , wherein the bone graft material further comprises an accelerant. 
   
   
       32 . The method of  claim 31 , wherein the accelerant is selected from the group consisting of calcium sulfate dihydrate, calcium sulfate dihydrate coated with sucrose, potassium sulfate, and sodium sulfate. 
   
   
       33 . The method of  claim 27 , further comprising applying the bone graft material to a bone defect. 
   
   
       34 . The method of  claim 27 , wherein the inorganic salt is selected from the group consisting of magnesium chloride, calcium chloride, sodium chloride, ammonium chloride, ammonium bromide, ammonium iodide, ammonium nitrate, ammonium sulfate, calcium bromide, calcium iodide, calcium nitrate, magnesium bromide, magnesium iodide, magnesium nitrate, sodium bromide, sodium iodide, sodium nitrate, potassium chloride, potassium bromide, potassium iodide, potassium nitrate, caesium chloride, caesium nitrate, caesium sulfate, zinc chloride, zinc bromide, zinc iodide, zinc nitrate, zinc sulfate, cupric chloride, cupric bromide, cupric nitrate, cupric sulfate, and combinations thereof. 
   
   
       35 . The method of  claim 27 , wherein the bone graft material has a compressive strength exceeding approximately 106 MPa within 24 hours after said mixing step. 
   
   
       36 . The method of  claim 27 , wherein upon application of the bone graft material to a bone defect, the bone graft material will have a compressive strength in excess of 15 MPa within one hour following application. 
   
   
       37 . The method of  claim 27 , wherein upon application of the bone graft material to a bone defect, the bone graft material will have a compressive strength in excess of 35 MPa within 24 hours following application. 
   
   
       38 . A bone graft material composition comprising a powder component and a diluent, the powder component comprising calcium sulfate hemihydrate prepared by immersing calcium sulfate dihydrate in a solution of water and an inorganic salt to form a mixture, and heating the mixture to substantially its boiling point at atmospheric pressure such that the calcium sulfate dihydrate is converted to calcium sulfate hemihydrate, and the diluent being present in an amount sufficient to provide a diluent to powder ratio between 0.19:1 and 0.31:1, wherein the powder component and the diluent are adapted for forming a bone graft material paste upon mixing. 
   
   
       39 . The composition of  claim 38 , wherein the calcium sulfate hemihydrate consists of thick, stubby, rod-like crystals having a low water carrying capacity. 
   
   
       40 . The composition of  claim 38 , wherein the powder component comprises between about 99.8 to 100 percent by weight calcium sulfate hemihydrate. 
   
   
       41 . The composition of  claim 38 , wherein the diluent to powder weight ratio is no more than 0.25:1. 
   
   
       42 . The composition of  claim 38 , wherein the bone graft material further comprises an accelerant. 
   
   
       43 . The composition of  claim 43 , wherein the accelerant is selected from the group consisting of calcium sulfate dihydrate, calcium sulfate dihydrate coated with sucrose, potassium sulfate, and sodium sulfate. 
   
   
       44 . The composition of  claim 38 , wherein the diluent is water or a solution comprising an inorganic salt or a cationic surface active agent. 
   
   
       45 . The composition of  claim 38 , wherein the bone graft material has a compressive strength exceeding approximately 106 MPa within 24 hours after said mixing step. 
   
   
       46 . The composition of  claim 38 , wherein upon application of the bone graft material to a bone defect, the bone graft material will have a compressive strength in excess of 15 MPa within one hour following application. 
   
   
       47 . The composition of  claim 38 , wherein upon application of the bone graft material to a bone defect, the bone graft material will have a compressive strength in excess of 35 MPa within 24 hours following application.

Join the waitlist — get patent alerts

Track US2009149553A1 — get alerts on status changes and closely related new filings.

We store only your email — no account needed. See our privacy policy.