Ceramic endosseous implant

Claim 2

A ceramic endosseous implant, comprising: a composite structural member having a ceramic outer member of polycrystalline alumina ceramic and a ceramic inner core member of single crystalline alumina ceramic; said outer member having a generally cylindrical shape and a cavity with micro-apertures on the outer surface thereof for permitting the penetration of a new bone and connective tissue thereinto; said inner member, of alumina ceramic, with a post portion adapted to be inserted in said cavity, a flange portion adjacent said post portion for the covering of said cavity, and a mounting post for use in attaching a prothesis; and said inner core member bonded to said outer member by a heat resistant glass cement having a coefficient of thermal expansion approximating that of alumina ceramic.

Claim 3

An implant according to claim 1 wherein said inner core member is made of a single crystalline ceramic.

Claim 4

An implant according to claim 1 wherein said cement has a coefficient of thermal expansion approximating that of said inner core member and said outer member.

Claim 5

An implant according to claim 1 wherein said cement has the following composition by weight: ______________________________________ SiO.sub.2 57% (by weight) B.sub.2 O.sub.3 23% Al.sub.2 O.sub.3 2% Na.sub.2 O.sub.3 3% BaO 7% ZnO 8% Total 100% ______________________________________

Claim 6

An implant according to claim 1 wherein said outer member comprises protuberances on its outer surface to aid in securely engaging surrounding tissue.

Claim 7

An implant according to claim 5 wherein said protrusion on said ceramic outer member is an external thread adapted to be threadedly fitted into said tissue.

Claim 8

An implant according to claim 5 wherein said protrusions on said ceramic outer member are formed by discontinuous ringlike or helical recesses adapted to engage said tissue.

Claim 9

A ceramic endosseous implant according to claim 1 wherein said micro-apertures have a diameter greater than 20 μm.

Claim 10

A ceramic endosseous implant according to claim 1 wherein said micro-apertures have a diameter of 20-700 μm.

Claim 11

A ceramic endosseous implant according to claim 1 wherein said micro-apertures have a diameter of 500 μm-5 mm.

Claim 12

A ceramic endosseous implant according to claim 1 wherein said outer member and said inner member are sintered together.

Claim 13

A ceramic endosseous implant according to claim 1 wherein said outer member and said inner member are threaded together.

Claim 14

An implant according to claim 1 wherein said cement is a heat-resistant Al 2 O 3 -based cement.

Claim 15

A ceramic endosseous implant, comprising: a composite structural member having a ceramic outer member of polycrystalline alumina ceramic and a ceramic inner core member of single crystalline alumina ceramic; said outer member, having a generally cylindrical shape and a cavity, manufactured to have material distributed therethrough in a predetermined configuration, said material being degradeable by new bone and connective tissue when said implant is inserted into a living being, forming micro-apertures in said outer member into which said new bone and connective tissue may penetrate; said inner member of alumina ceramic, configured to reinforce said outer member, with a post portion adapted to be inserted in said cavity, a flange portion adjacent said post portion for the covering of said cavity, and a mounting post for use in attaching a prothesis; said inner core member bonded to said outer member by a heat resistant glass cement having a coefficient of thermal expansion approximating that of alumina ceramic.

Claim 16

A ceramic endosseous implant, comprising: a composite structural member having a ceramic outer member of polycrystalline alumina ceramic and a ceramic inner core member of single crystalline alumina ceramic; said outer member, having a generally cylindrical shape and a cavity, manufactured to have material distributed therethrough in a predetermined configuration, said material being degradeable by new bone and connective tissue when said implant is inserted into a living being, forming micro-apertures in said outer member into which said new bone and connective tissue may penetrate; said inner member of alumina ceramic, configured to reinforce said outer member, with a post portion adapted to be inserted in said cavity, a flange portion adjacent said post portion for the covering of said cavity, and a mounting post for use in attaching a prothesis; said inner core member bonded to said outer member by a heat resistant glass cement having a coefficient of thermal expansion approximating that of alumina ceramic.

Claim 17

A ceramic endosseous implant comprising a composite structural member having a ceramic outer member of polycrystalline alumina ceramic and a ceramic inner core member fused together by a glass cement having a coefficient of thermal expansion approximating that of alumina ceramic, said outer member having micro-apertures on the outer surface thereof for permitting the penetration of new bone and connective tissue thereinto, and said inner member made of single crystalline alumina ceramic and configured to reinforce said outer member.

Claim 18

A ceramic endosseous implant comprising a composite structural member having a ceramic outer member of polycrystalline alumina ceramic and a ceramic inner core member fused together by a glass cement having a coefficient of thermal expansion approximating that of alumina ceramic, said outer member having micro-apertures on the outer surface thereof for permitting the penetration of new bone and connective tissue thereinto, and said inner member made of single crystalline alumina ceramic and configured to reinforce said outer member.

Claim 19

A ceramic endosseous implant according to claim 14 wherein said outer member and said inner core member are threaded together.

Claim 20

An implant according to claim 14 wherein said material comprises apatite.

Claim 21

A ceramic outer member, having a cavity, for permanent insertion into body tissues, having an outer surface contacting said tissues and formed to encourage the growth of said tissues into said member, and further having a shape to mechanically engage said tissues during said growth; a single crystalline ceramic inner core member shaped to fill said cavity and to provide an protrusion for attaching a prothesis; said inner core member permanently affixed to said outer member by a glass cement having coefficient of thermal expansion approximating that of said outer and inner core members.

Claim 22

A ceramic outer member, having a cavity, for permanent insertion into body tissues, having an outer surface contacting said tissues and formed to encourage the growth of said tissues into said member, and further having a shape to mechanically engage said tissues during said growth; a single crystalline ceramic inner core member shaped to fill said cavity and to provide an protrusion for attaching a prothesis; said inner core member permanently affixed to said outer member by a glass cement having coefficient of thermal expansion approximating that of said outer and inner core members.

Claim 23

An implant according to claim 18 wherein the outer surface of said outer member contains micro-apertures of size to encourage the growth of said tissues into said apertures.

Claim 24

An implant according to claim 19 wherein the size of said micro-apertures are selectively apportioned in accordance with a desired ratio of growth into said apertures of bone and connective tissues to provide an affixation of said member having predetermined proportion of strength and elasticity.

Claim 25

An implant according to claim 18 wherein said outer member's outer surface comprises a material able to be degraded and replaced by tissue in contact with said material.

Claim 26

An implant according to claim 21 wherein said material comprises apatite.

Claim 27

An implant according to claim 18 wherein said cement has penetrated the surfaces of said inner core and outer member in contact with each other and fused said members together.