Machinable preformed calcium phosphate bone substitute material implants
AssigneeEtex Corporation
InventorsAliassghar N. Tofighi, Michele Krause, Dosuk D. Lee
Life of this patent
Estimating the term…
Abstract
The present invention provides machinable calcium phosphate bone substitute material implants having mechanical properties comparable to those of natural bone. The implants include intimately mixed solid precursor materials that react under physiological conditions to form poorly-crystalline hydroxyapatite and eventually are remodeled into bone in vivo. The implants can include a biocompatible polymer to increase density and strength and control resorbability.
Claims40
A bone implant comprising an unhydrated calcium phosphate precursor capable of forming poorly-crystalline hydroxyapatite in vivo upon hydration at the implantation site, wherein the precursor has a calcium to phosphorous atomic ratio between about 1.2 and about 1.68, and
- wherein the implant has a compressive strength of at least about 60 MPa.
A bone implant comprising:
- (a) a first calcium phosphate that is an amorphous calcium phosphate;
- and
- (b) in intimate mixture with the first calcium phosphate, a second calcium phosphate having greater crystallinity than the first calcium phosphate;
- wherein the overall calcium to phosphorous atomic ratio is between about 1.2 and about 1.68 and said first and second calcium phosphates are unhydrated;
- and
- wherein the implant has a compressive strength of at least about 60 MPa.
A method of bone implantation comprising:
- (a) providing a bone implant comprising an unhydrated calcium phosphate precursor capable of forming poorly-crystalline hydroxyapatite in vivo upon hydration at the implantation site, wherein the precursor has a calcium to phosphorous atomic ratio between about 1.2 and about 1.68, and wherein the implant has a compressive strength of at least about 60 MPa;
- and
- (b) securing the bone implant at a site requiring implantation,
- whereby the precursor undergoes conversion to poorly-crystalline hydroxyapatite at the implantation site.
A method of spinal fusion comprising:
- (a) providing a bone implant comprising:
- (i) a first calcium phosphate that is an amorphous calcium phosphate;
- and
- (ii) in intimate mixture with the first calcium phosphate, a second calcium phosphate having greater crystallinity than the first calcium phosphate;
- wherein the overall calcium to phosphorous atomic ratio is between about 1.2 and about 1.68 and said first and second calcium phosphates are unhydrated;
- and
- wherein the implant has a compressive strength of at least about 60 MPa;
- and
- (b) securing the bone implant between adjacent spinal vertebrae to promote fusion of the vertebrae.
A method of spinal fusion comprising:
- (a) providing a bone implant comprising an unhydrated calcium phosphate precursor capable of forming poorly-crystalline hydroxyapatite in vivo upon hydration at the implant site, wherein the precursor has a calcium to phosphorous atomic ratio between about 1.2 and about 1.68, and wherein the implant has a compressive strength of at least about 60 MPa;
- and
- (b) securing the bone implant between adjacent spinal vertebrae to promote fusion of the vertebrae.
A method of bone implantation comprising:
- (a) providing a bone implant comprising:
- (i) a first calcium phosphate that is an amorphous calcium phosphate;
- and
- (ii) in intimate mixture with the first calcium phosphate, a second calcium phosphate having a greater crystallinity than the first calcium phosphate;
- wherein the overall calcium to phosphorous atomic ratio is between about 1.2 and about 1.68 and said first and second calcium phosphates are unhydrated;
- and
- wherein the implant has a compressive strength of at least about 60 MPa;
- and
- (b) securing the bone implant at a site requiring implantation;
- whereby the first and second calcium phosphates undergo conversion to poorly-crystalline hydroxyapatite upon hydration at the implantation site.
Dependencies are inferred from the claim text.