Arrangement for obtaining reliable anchoring of a threaded implant in a bone

Patent metadata

Field	Value
Publication number	US-9375295-B2
Application number	US-201414524742-A
Country	US
Kind code	B2
Filing date	Oct 27, 2014
Priority date	Nov 11, 1997
Publication date	Jun 28, 2016
Grant date	Jun 28, 2016

Abstract

In an arrangement for obtaining reliable anchoring of a threaded implant in dentine, a hole is made in the bone substance. In the side wall of the hole it is possible to establish an internal threading which can cooperate with an external threading on the implant. The implant threading is arranged to force the bone substance out in essentially radial directions as a function of the extent to which the implant is screwed into the hole. The threading is arranged to effect greater forcing out of the bone substance at the outer parts of the hole than at the inner parts of the hole. The degree of forcing out is adapted in relation to the softness of the bone in order to achieve the reliable anchoring. Along at least part of the longitudinal direction of the implant, the implant threading can be given a non-circular configuration for the purpose of obtaining improved rotational stability in soft/weak bone.

First claim

The invention claimed is:

1. A threaded implant for obtaining reliable anchoring in a bone substance of a human, the implant comprising:
an external threading on the implant that can cooperate with a side wall of a hole in the bone substance for reliable anchoring and healing-in of the implant;
the external threading having a slight conicity;
the external threading extending along most of a length of the implant to force the bone substance out in essentially radial directions as a function of the extent to which the implant is screwed into the hole in the bone;
the external threading including two or more thread spirals for providing a tight threading on the implant; and,
the implant having a tip part merging into a remaining part, wherein the implant threading has a stronger conicity at the tip part than at the remaining part,
wherein the external threading along at least part of the longitudinal direction of the implant is given a non-circular or eccentric configuration for obtaining improved stability of the implant in a recently inserted state or an incorporated state of the implant in soft or weak bone substance.

2. The threaded implant according to claim 1 , wherein the external threading has a gradually increasing diameter as seen from the tip part of the implant to ensure that a pressure between the bone substance and the implant has essentially a slightly increasing value during a greater part of the operation of screwing the implant into the hole in the bone substance.

3. The threaded implant according to claim 1 , wherein the conicity of the threading at the remaining part has an angle of inclination of 0.5° to 2°, and wherein the conicity of the threading at the tip part has an angle of inclination of 10° to 15°, and wherein the tip part has a length which is 10 to 30° of a length of a total implant threading.

4. The threaded implant according to claim 1 , wherein the tip part of the implant has a circular or concentric threading which merges gradually into a non-circular or eccentric threading on the remaining part of the implant.

5. The threaded implant according to claim 1 , wherein peripheries of the different non-circular or eccentric thread cross-sections have beveled corners.

6. The threaded implant according to claim 1 , wherein the non-circularity is arranged such that areas of maximum diameter are displaced in the peripheral direction from one thread turn to the next thread turn.

7. The threaded implant according to claim 1 , wherein the number of thread spirals is two, three or four.

8. The threaded implant according to claim 7 , wherein the number of cutting edges is the same or a multiple of the number of thread spirals so that symmetrical cutting forces are obtained.

9. The threaded implant according to claim 8 , wherein two thread spirals are arranged on the implant together with two or four cutting edges, or wherein three threaded spirals are arranged together with three cutting edges.

10. The threaded implant according to claim 1 , wherein the bone substance is soft bone substance.

11. A threaded implant for obtaining reliable anchoring in a bone substance of a human, the implant comprising:
an external threading on the implant that can cooperate with a side wall of a hole in the bone substance for reliable anchoring and healing-in of the implant;
wherein the external threading along at least part of the longitudinal direction of the implant is given a non-circular or eccentric configuration for obtaining improved stability of the implant;
wherein the tip or free end of the implant has a circular or concentric thread which merges into a non-circular or eccentric thread on the remaining part or parts of the implant;
wherein the non-circularity or eccentricity can be provided on the thread supporting body and/or on the outer portion of each thread; and,
wherein the threaded implant is provided to support a dental prosthesis.

12. A threaded implant for obtaining reliable anchoring in a bone substance of a human, the implant comprising:
a thread bearing body; and,
an external threading on the thread bearing body that can cooperate with a side wall of the hole in the bone substance for reliable anchoring and healing in of the implant;
wherein the thread bearing body and/or the external threading along at least a part of the longitudinal direction of the implant has a non-circular or eccentric cross-sectional configuration;
wherein a tip of a free end of the thread bearing body of the implant and/or the external threading has a circular or concentric cross-sectional configuration; and,
wherein the threaded implant is provided to support dental prosthesis.

13. The threaded implant of claim 12 , wherein the external threading has a conicity.

14. The threaded implant of claim 12 , wherein the external threading has two or more thread spirals.

15. The threaded implant of claim 12 , wherein the non-circular or eccentric cross-sectional configuration consists of three protruding parts, each protruding part having an arcuate cross-sectional shape.

16. The threaded implant of claim 15 , wherein the thread bearing body along at least a part of the longitudinal direction of the implant is given a non-circular or eccentric cross-sectional configuration and the tip of the free end of the thread bearing body of the implant has a circular or concentric cross-sectional configuration.

17. The threaded implant of claim 16 , wherein the external threading along at least a part of the longitudinal direction of the implant is given a non-circular or eccentric cross-sectional configuration and the tip free end of the external threading has a circular or concentric cross-sectional configuration.

Assignees

• Nobel Biocare Services Ag

Inventors

• Carlsson Lennart
• Engman Fredrik
• Fromell Roger
• Joerneus Lars

Classifications

• A61C8/0089

  Implanting tools or instruments · CPC title

• A61C8/005

  Connecting devices for joining an upper structure with an implant member, e.g. spacers · CPC title

• A61C8/0025 Primary

  with multiple threads · CPC title

• A61C8/0068

  with an additional screw · CPC title

• A61C8/0022 Primary

  Self-screwing (A61C8/0028 takes precedence) · CPC title