Implant that can be implanted in osseous tissue, method for producing said implant and corresponding implant

• US 8,911,234 B2
• Filed: 01/28/2005
• Issued: 12/16/2014
• Est. Priority Date: 02/20/2004
• Status: Active Grant

• Current Assignee: Woodwelding AG
• Original Assignee: Woodwelding AG
• Inventors: Mayer, Jorg, Aeschlimann, Marcel, Torriani, Laurent, Rast, Christopher, Muller, Andrea
• Primary Examiner(s): EIDE, HEIDI MARIE
• Application Number:
  US10/530,684
• Publication Number:
  US 20060105295A1
• Time in Patent Office: 3,609 Days
• Field of Search: 433172-177, 433/180, 606/72, 606/232, 606/67, 606/300, 606/329, 606/60, 411/490, 411/456, 411/451.3, 411/487, 411/82.1, 623/17.17, 623/23.26, 623/23.24, 623/23.31, 623/23.37, 623/16.11
• US Class Current: 433/173
• CPC Class Codes: A61B 17/68 Internal fixation devices , including fasteners and spinal fixators, even if a part thereof projects from the skin bone staples A61B17/0642
• CPC Class Codes: A61B 2017/00955 thermoplastic
• CPC Class Codes: A61C 13/0003 Making bridge-work, inlays, implants or the like
• CPC Class Codes: A61C 13/0004 Computer-assisted sizing or machining of dental prostheses
• CPC Class Codes: A61C 8/0012 characterised by the material or composition, e.g. ceramics, surface layer, metal alloy use of specific materials A61K6/00
• CPC Class Codes: A61C 8/0016 polymeric material
• CPC Class Codes: A61C 8/0018 characterised by the shape
• CPC Class Codes: A61C 8/0045 with a stepped body
• CPC Class Codes: A61C 8/0089 Implanting tools or instruments
• CPC Class Codes: A61F 2002/30065 thermoplastic, i.e. softening or fusing when heated, and hardening and becoming rigid again when cooled
• CPC Class Codes: A61F 2002/4683 by applying ultrasonic vibrations
• CPC Class Codes: A61F 2210/0071 thermoplastic

Abstract

A bone implant (10) is implanted in a cavity parallel to an implant axis (l) and without substantial rotation. The implant includes, on an implant portion to be implanted, cutting edges (14), which do not extend in a common plane with the implant axis and are facing toward the distal end of the implant. The implant also includes surface ranges (16) of a material that is liquefiable by mechanical oscillations. The cutting edges (14) are dimensioned such that they are lodged in the cavity wall after implantation. For implantation, the implant is impinged with mechanical oscillations, resulting in the thermoplastic material being at least partially liquefied and pressed into unevennesses and pores of the cavity wall to form a form-fit and/or material-fit connection between implant (10) and cavity wall, when re-solidified. The cutting edges (14) anchor the implant in the cavity wall.

Claims

1. A bone implant shaped to be implanted in an implantation direction parallel to an implant axis in a cavity surrounded by a cavity wall of bone tissue and comprising:

an implant portion to be implanted, said implant portion having an outer surface and an inner surface, said outer surface defining depressions and chip forming cutting edges, said inner surface including energy directors and defining a hollow space that receives liquefiable material that is liquefied by mechanical oscillation, wherein openings that lead from the hollow space to the depressions are formed through the implant portion, said openings serving as passageways to direct and communicate liquefied material from the hollow space to the depressions and thereby form surface ranges at predefined locations on the outer surface of the implant portion that protrude from the depressions, and wherein the energy directors are disposed at an inlet to the openings; and

wherein the chip forming cutting edges are capable of cutting the cavity wall of bone tissue, said cutting edges not extending in a common plane with the implants axis, said cutting edges facing toward a distal end region of the implant and extending at least partly around the circumference of the implant, and wherein said cutting edges are spaced from the implant axis by implants-axis-to-cutting-edges-distances, which are decreasing in the implanting direction.

2. The bone implant according to claim 1, wherein the cutting edges are designed to be salient.

3. The bone implant according to claim 1, wherein the cutting edges are undercut to form a chip space.

4. The bone implant according to claim 1, wherein a proximal end region of the implant comprises a collar with a lower edge fashioned as a cutting edge.

5. The bone implant according to claim 4, wherein the proximal end region comprises a ring of a thermoplastic material.

6. The bone implant according to claim 1, further comprising a piston, said piston being insertable into a proximal opening of the hollow space.

7. The bone implant according to claim 6, wherein, on a proximal end of the piston and/or round the proximal opening of the hollow space, an insulating connection between piston and implant is provided.

8. The bone implant according to claim 1, wherein said implant carries an intermediate element on a proximal end region.

9. The bone implant according to claim 8, wherein the intermediate element is connected to the implant by a loose fit connection and/or is equipped to be joined to a sonotrode via a loose fit connection.

10. The bone implant according to claim 1, wherein said implant is a dental implant.

11. The bone implant according to claim 10, wherein said cutting edges are comprising a wedge angle β

between a proximal and a distal cutting edge surface of less than 90°

.

12. The bone implant according to claim 1, wherein the implant portion to be implanted comprises at least some non-circular cross sections at a right angle to the implant.

13. A bone implant suitable for implantation in an implantation direction parallel to an implant axis in a cavity surrounded by a cavity wall of bone tissue comprising an implant portion, wherein the implant portion to be implanted comprises exterior surface ranges formed by pressing liquefiable material out of a hollow space in the implant through openings that extend through the implant portion, and wherein the implant portion further comprises energy directors at an inlet to the openings to direct liquefied material into the openings and chip forming cutting edges being disposed on an exterior of the implant portion and being capable of cutting the cavity wall of bone tissue, said cutting edges not extending in a common plane with the implant axis, said cutting edges facing toward a distal end region of the implant and extending at least partly around the circumference of the implant, wherein said cutting edges comprise a wedge angle β

between a proximal and a distal cutting edge surface of less than 90°

, a clearance angle α

between the proximal edge surface and a cylindrical surface rotated around the implant axis with a sum of a plus β

being smaller than 90°

, and an angle Υ

between the distal cutting edge surface and the implant axis of 90°

or less and wherein said cutting edges are distanced from the implant axis by implant-axis-to-cutting-edge-distances, which implant-axis-to-cutting-edge-distances are decreasing in the implanting direction.

14. A bone implant shaped to be implanted without substantial rotation in an implantation direction parallel to an implant axis into a cavity in bone tissue wherein an implant portion to be implanted comprises:

an interior surface defining an energy director, said energy director being at an inlet to an opening extending through said implant portion;

cutting edges and exterior surface ranges of a material which is liquefiable by mechanical vibration,

and wherein said cutting edges;

are not extending in a common plane with the implant axis,

are chip forming cutting edges capable of cutting a cavity wall of bone tissue,

are facing toward a distal end region of the implant and are extending at least partly around the circumference of the implant,

wherein said exterior surface ranges are formed by pressing the liquefiable material out of a hollow space in the implant and through the opening to the outer surface of the implant.

15. The bone implant according to claim 14, being a dental implant.

16. The bone implant according to claim 14, the cavity in bone tissue being surrounded by a cavity wall of bone tissue.

17. The bone implant according to claim 14, wherein said cutting edges are comprising a wedge angle β

between a proximal and a distal cutting edge surface of less than 90°

.

18. The bone implant according to claim 14, wherein said cutting edges are distanced from the implant axis by implant-axis-to-cutting-edge-distances, which are decreasing in the implanting direction.

19. The bone implant according to claim 14, wherein said cutting edges are shaped to be reaming as they are moved into the bone tissue.

20. The bone implant according to claim 14, wherein osseointegrative surface areas are situated between the surface ranges of the liquefiable material.

21. The bone implant according to claim 14, wherein the implant portion to be implanted further comprises axially extending furrowing or tapping structures.

22. The bone implant according to claim 14, wherein the bone implant is a shaft of a joint prosthesis.

23. The bone implant according to claim 14, wherein the implant is adapted to bridge a bone defect.

24. A bone implant shaped to be implanted without substantial rotation in an implantation direction parallel to an implant axis into a cavity of bone tissue comprising:

a root portion having the shape of an irregular cone with at least some of its cross sections not being round and/or its axis not being straight suitable for implantation in an implantation direction parallel to an implant axis in a cavity surrounded by a cavity wall of bone tissue and comprising an implant portion to be implanted,

wherein the implant portion to be implanted comprises an interior surface defining an energy director, said energy director being at an inlet to an opening extending through said implant portion, said implant portion further comprising exterior surface ranges formed on the outer side of the implant by pressing the liquefiable material out of a hollow space in the implant through the openings to the outer surface of the implant,

and wherein the implant portion to be implanted further comprises chip forming cutting edges capable of cutting the cavity wall of bone tissue, said cutting edges not extending in a common plane with the implant axis, and said cutting edges facing toward a distal end region of the implant and extending at least partly around the circumference of the implant.