U.S. patent application number 10/574313 was filed with the patent office on 2007-05-24 for implant arrangement with an internal socket for a turning tool.
Invention is credited to Sanel Duric, Lars Jorneus.
Application Number | 20070117066 10/574313 |
Document ID | / |
Family ID | 29247001 |
Filed Date | 2007-05-24 |
United States Patent
Application |
20070117066 |
Kind Code |
A1 |
Jorneus; Lars ; et
al. |
May 24, 2007 |
Implant arrangement with an internal socket for a turning tool
Abstract
An implant is provided with an upper portion in which an
internal socket extends. The implant (12) can be tightened by means
of a turning instrument (11) which has first lateral surfaces (14)
that can cooperate with corresponding second lateral surfaces (15)
in the internal socket. One or more of the first and/or second
lateral surfaces is/are arranged completely or partially with
friction-enhancing means (16). The implant and the tool are
arranged with interacting parts which extend beyond the first and
second lateral surfaces and completely or substantially take up
bending moments (M, M') which act in or on said portion or are
directed toward said portion and occur in the event of skewing, or
a tendency toward skewing, between the implant and the tool. The
arrangement counteracts mechanical stresses in said portion, the
latter being able to retain its original shape even in the case of
implants with small dimensions.
Inventors: |
Jorneus; Lars;
(Riabergsvagen, SE) ; Duric; Sanel; (Lundgren,
SE) |
Correspondence
Address: |
KNOBBE MARTENS OLSON & BEAR LLP
2040 MAIN STREET
FOURTEENTH FLOOR
IRVINE
CA
92614
US
|
Family ID: |
29247001 |
Appl. No.: |
10/574313 |
Filed: |
September 24, 2004 |
PCT Filed: |
September 24, 2004 |
PCT NO: |
PCT/SE04/01372 |
371 Date: |
December 13, 2006 |
Current U.S.
Class: |
433/173 |
Current CPC
Class: |
A61C 8/0037 20130101;
A61B 17/8615 20130101; A61B 17/8877 20130101; A61C 8/0087 20130101;
A61C 8/0089 20130101; A61C 2008/0046 20130101; A61C 8/0018
20130101 |
Class at
Publication: |
433/173 |
International
Class: |
A61C 8/00 20060101
A61C008/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 1, 2003 |
SE |
0302597-0 |
Claims
1. A dental implant assembly for counteracting stress in a portion
of the dental implant assembly, the assembly comprising a dental
implant provided with an internal socket, a turning instrument
which is configured to engage the internal socket and to turn the
dental implant, wherein the turning instrument has first lateral
surfaces (14) that can cooperate with corresponding second lateral
surfaces in the internal socket, and wherein one or more of the
first or second surfaces are provided with means for enhancing
friction between the turning instrument and the internal socket; or
wherein the dental implant and the turning instrument comprise
interacting parts which extend inside the dental implant and beyond
the first and second lateral surfaces, the interacting parts being
configured to take up bending moments between the dental implant
and the turning instrument.
2. (canceled)
3. The dental implant assembly as in claim 1, wherein a cross
section through the lateral surfaces have non-round geometries.
4. The dental implant assembly as in claim 1, wherein the means for
enhancing friction between the turning instrument and the internal
socket comprises a friction-enhancing coating on the first lateral
surfaces.
5. The dental implant assembly as in claim 1, wherein the means for
enhancing friction between the turning instrument and the internal
socket comprises a friction-enhancing coating on the second lateral
surfaces.
6. The dental implant assembly as in claim 1, wherein the means for
enhancing friction between the turning instrument and the internal
socket comprises a chosen degree of roughness on the lateral
surfaces.
7. The dental implant assembly as in claim 1, wherein interaction
between the first and second lateral surfaces is configured to take
place only when a degree of loading or degree of turning of the
dental implant and the turning instrument tool is reached.
8. The dental implant assembly as in claim 1, wherein materials
which interact during turning, are configured to enhance
friction.
9. The dental implant assembly as in claim 1, wherein the means for
enhancing friction between the turning instrument and the internal
socket comprises a metal nitride and/or metal carbide, applied to
the lateral surfaces.
10. The dental implant assembly as in claim 1, wherein the means
for enhancing friction between the turning instrument and the
internal socket comprises diamond particles applied to the lateral
surfaces.
11. The dental implant assembly as in claim 9, wherein titanium
nitride is applied and arrangeme stress between the dental implant
and the turning instrument is reduced by up to about 30%.
12. The dental implant assembly as in claim 1, wherein the part of
the tool extending beyond the first surfaces is about 3 to 5 times
longer than the longitudinal length the first lateral surfaces.
13. The dental implant assembly as in claim 1, wherein that the
part of the tool extending beyond the first surfaces has first and
second longitudinally extending parts with different diameters, the
first longitudinally extending part situated next to the first
lateral surfaces having a greater diameter than the second
longitudinally extending parts.
14. The dental implant assembly as in claim 13, wherein a bending
moment which occurs in the event of skewing between the dental
implant and the turning instrument tool places a load on surface
areas of the dental implant which are located at the first
longitudinal extending part's area nearest to the first lateral
surfaces, and the outermost part of the second longitudinally
extending part, which bending moment is prevented from acting on
the portion with the internal socket by a slight clearance that is
initially present between the first and second lateral
surfaces.
15. The dental implant assembly as in claim 14, wherein threads
parts of the implant which bear said threads take up said bending
moments.
Description
[0001] The present invention relates to an arrangement for
counteracting stress in a portion of an implant provided with an
internal socket extending in said portion, via which the implant
can be tightened by means of a turning tool or turning instrument
which has first lateral surfaces that can cooperate with
corresponding second lateral surfaces in the internal socket.
[0002] It is already known to anchor implants in holes in the jaw
bone with the aid of instruments or tools. The implant can be
fitted in a threaded hole or can be of the self-tapping type. It
can be screwed in using said internal socket for the tool, and the
present invention relates to this type of implant. Reference is
here made in quite general terms to implants and methods which are
generally known in dentistry in connection with screwing-in of
implants.
[0003] An implant with an internal socket affords advantages, such
as easier connection of spacer elements and other components to the
implant. The necessary implantation force/turning force can,
however, be relatively high, and the material thickness of the
implant is often low, especially in the case where the implant is
of small dimensions. This can result in the implant being deformed
or being at risk of breaking at the site where the turning force is
applied. One reason for this happening is that the internal socket,
which has a non-round geometry, is often a polygon or some other
geometrical figure that results in outwardly directed forces when
the implant is being turned into its position. This results in
stresses in the implant which act outward and which force the
material out and apart. The most obvious way of improving this
situation would be to change the non-round geometry so that the
outwardly directed forces were reduced. However, this can often be
difficult to do in practice, for production technology reasons
among others. In established implant systems, these geometries are
already defined, and a large range of known ancillary components
are based on these geometries. Changing the geometry would
therefore be associated with considerable costs and would cause
great technical problems. The invention aims, inter alia, to solve
these problems.
[0004] Another type of load which can occur on a portion with said
socket is a bending load, and this can occur either as the sole
problem or as a problem in combination with the disadvantages of
the turning forces. If one wishes to change the direction of the
implant during implantation thereof, or if the angled handpiece or
wrench is not applied properly to the tool/implant, a bending force
is exerted which will deflect the implant and which, in addition to
producing undesired deformation, can also lead to fracturing of the
implant portion/flange which has the socket. The invention also
aims to solve this problem.
[0005] The feature which can principally be regarded as
characterizing a first combination part of the invention is that
one or more of the first and/or second lateral surfaces is/are
completely or partially arranged with friction-enhancing means. A
second combination part, which can function independently or in
combination with the first combination part, can principally be
regarded as being characterized in that the implant and the tool
are arranged with interacting parts which extend inside the implant
and beyond the first and second lateral surfaces and substantially
take up bending moments which act in or on said portion or are
directed toward said portion and occur in the event of skewing, or
a tendency toward skewing, between the implant and the tool.
[0006] In further developments of the inventive concept, the means
can comprise or consist of a friction-enhancing coating on the
first and second surface or surfaces of the tool and implant,
respectively. In one embodiment, the means can consist of a chosen
degree of roughness on the lateral surface or surfaces concerned.
In a second embodiment, the means can consist of the fact that
parts of the implant and of the tool which interact during turning
are designed to bring about increased friction, which is thus
achieved by suitable choice of material for the respective parts of
the implant and of the tool/instrument. In a further embodiment,
the means can consist of or comprise metal nitrides and/or metal
carbides, e.g. titanium nitride, chromium carbide or diamond
particles, etc., applied to the surface or surfaces concerned. In a
further embodiment, the interaction between the first and second
lateral surfaces can be designed to take place only when a degree
of loading on the implant and the tool is reached. In one
embodiment, the arrangement can also be characterized in that the
stress in the implant portion in question can be reduced by up to
ca. 30% when titanium nitride is applied.
[0007] That part of the tool extending beyond said first surfaces
can be ca. 3 to 5 times longer than the longitudinal extents of the
first surfaces. Said part extending past can have first and second
longitudinally extending parts with different diameters, the first
longitudinally extending parts situated next to the first lateral
surfaces having the greater diameter. In the event of skewing
tendencies or skewing between the implant and the tool, a bending
moment occurs which places a load on, inter alia, surface areas of
the implant located at the first longitudinally extending part's
area nearest to the first lateral surfaces and the outermost part
of the second longitudinally extending part. The bending moment is
prevented from acting on the portion with the internal socket by
virtue of the fact that a slight clearance is initially present
between the first and second lateral surfaces. Threads on the
implant can also contribute to taking up said bending moments.
[0008] By means of what has been proposed above, the stresses
acting on the implant flange or portion with the internal socket
can be greatly reduced. The advantages of the internal socket on
the implant can be retained, and good stability characteristics can
be obtained even for implants of small dimensions. The various
friction-enhancing means proposed can be combined and/or optimized
according to the respective application so as to achieve higher
coefficients of friction. The guide pin on the instrument or tool
can be considerably lengthened and it will be appreciated, for
example, that if the effective length of the pin is doubled, for
example, the force in the flange portion reduces by half on account
of the fact that the pin can exploit the resistance it meets in the
implant.
[0009] A presently proposed embodiment of an arrangement with the
characteristics of the invention is described below with reference
to the attached drawings, in which:
[0010] FIG. 1 is an end view showing the end surface of a portion
or a flange which, in an implant, is provided with an internal
socket,
[0011] FIG. 2 is an end view showing the flange/portion according
to FIG. 1, but where said flange/portion has been exposed to an
outwardly acting force associated with a turning tool or turning
instrument (not shown), this outward movement also having caused a
deformation of the circumference of the flange/portion,
[0012] FIG. 3 is a longitudinal view showing a tool applied to an
implant (part of which is shown) which has been anchored in a jaw
bone (part of which is shown),
[0013] FIG. 4 is a longitudinal section showing the construction of
an implant in question,
[0014] FIG. 5 is an end view of the implant according to FIG.
4,
[0015] FIG. 6 is a vertical view showing first and second lateral
surfaces coated with friction-enhancing means, when the tool is in
a state in which it is not turned in relation to the implant,
and
[0016] FIG. 7 shows a vertical view during interaction with
intermediate means, when the tool is turned relative to the
implant.
[0017] In FIG. 1, a portion of an implant is indicated by 1. The
portion constitutes an upper or outer part of the implant and
comprises an internal socket 2 for a tool or instrument, described
below. In the view shown, the wall of the socket has a polygonal
shape with three bulges 3, 4 and 5 and, extending between these,
wall parts 6, 7 and 8 with smaller radii. The radii of the bulges
3, 4, 5 are represented by R, and the radii of the wall parts 6, 7
and 8 are represented by r. The circumference is indicated by
9.
[0018] FIG. 2 shows an example of how material is forced outward in
the already known case. The forcing out or bursting action has
caused the circumference 9' to lose its circular shape 9 according
to FIG. 1. It will be appreciated that this forcing-out or
bursting-out of the material is of great disadvantage for the
fixture which is to be applied to the implant. It can, for example,
result in accumulation of bacteria, loss of tolerance, etc., in
respect of the future fixture.
[0019] FIG. 3 shows a turning instrument or turning tool 11 applied
to an implant 13 which is or can be anchored in a jaw bone 12. In
accordance with the invention, the tool has first lateral surfaces
14 which can cooperate with second lateral surfaces 15 on the
implant. In cross section, i.e. at right angles to the plane of the
figure according to FIG. 3, the configuration of the first lateral
surfaces can correspond to that of the inner walls 3-B in FIG. 1.
The second lateral surfaces of the implant can have the
configurations shown by 3-8 in FIG. 1. Means 16 on said first and
second lateral surfaces are also indicated symbolically in FIG. 3.
The means 16 will be arranged to give the turning instrument or
turning tool a higher coefficient of friction compared to the case
when no such means 16 is present. The flange or portion bearing the
internal socket of the implant is indicated by 17 in FIG. 3. The
flange or portion has a length 1. The tool 11 is provided with a
prolonged guide pin 18 which is made up of two guide pin parts 18a
and 18b of different diameters. The guide pin part 18a of greater
diameter is situated nearest to the drive part of the tool
indicated by 19. The turning tool or turning instrument 11 is of a
type which in principle is known per se and it will therefore not
be described in detail here. Reference may be made generally to the
tool or instrument of the type disclosed in Swedish patent
98/03849-0. The guide pin has a length L which is 3 to 5 times
longer than the length 1 of the drive part. The implant is provided
with internal recesses 20 and 21 for said guide pin parts 18a and
18b, which are arranged with unthreaded outer surfaces. In the
position shown in FIG. 3, the guide pin has a slight clearance 22
in relation to the opposing inner wall of the implant, which inner
wall can be threaded. In addition, there is a clearance 23 between
the drive part 14 of the tool and the opposing inner wall of the
implant. Said clearance 23 is initially present when the tool or
instrument is in a state in which it is not turned in relation to
the implant. Said clearances 22, 23 are also chosen such that
bending moments can be taken up by the guide pin parts 18a and 18b
when the tool 11 is skewed or has a tendency to skew relative to
the implant, i.e. when the longitudinal axis 24 of the tool is
angled in relation to the corresponding longitudinal axis of the
implant. Said bending moments are symbolized by M, M'. The
clearance is then to be such that the guide pin by itself takes up
most of the bending moment, and the drive part 14 is largely
prevented from pressing the flange or portion 17 radially outward,
compared to the case according to FIG. 2.
[0020] FIG. 4 shows, inter alia, the internal surfaces 20 and 21 of
the implant which constitute guide surfaces for the tool parts 18a
and 18b in FIG. 3. The figure also shows the means 16 arranged in
connection with the second inner surfaces (indicated symbolically
by 25) of the flange or portion 17 of the implant. The recess 21 is
threaded in order to participate in a securing function for an
implant screw (not shown) used for fitting a dental replacement
part on the implant.
[0021] FIG. 5 shows, inter alia, the clearance 23 between the first
and second lateral surfaces of the tool and implant, respectively.
Said clearance is present when the tool is in a position not turned
relative to the implant. This clearance means that, in the event of
the bending moments discussed above, the tool is largely prevented
from pressing the material of the flange or portion 17 outward in
the radial direction. Reference number 25 designates the contact
between parts of the first lateral surfaces and corresponding parts
of the second lateral surfaces 26. It will be appreciated that the
turning interaction takes place only at the parts concerned. In the
present case, the direction of turning is clockwise, as has been
indicated by the arrow 27.
[0022] FIG. 6 shows the case where the opposing first and second
lateral surfaces 14' and 17' are in the state in which the turning
tool is not turned relative to the implant. The clearance 23 is
present between the surfaces. A first means 28 is arranged on the
first lateral surface of the tool, and a second means 29 is
arranged on the second lateral surface of the flange or portion.
These means can in principle be the same means or consist of
different means. Alternatively, only one of the first and second
lateral surfaces can be provided with said means. In accordance
with the above, the means can consist of a chosen surface
roughness, metal nitrides and/or metal carbides, such as titanium
nitride or chromium carbide, or a mixture of these means, diamond
particles, different material selections, etc., see above. In FIG.
4, the internal thread on the implant 12 is indicated by 21'. A
surface area of the implant 12 which participates in taking up the
bending moment M is indicated by 21'', and a surface area which
takes up the bending moment M' is indicated by 20'.
[0023] FIG. 7 shows the case where the opposing first and second
lateral surfaces 14' and 17' cooperate with one another via the
intermediate means, i.e. when the turning tool is turned in
relation to the implant. The contact between the surfaces is
indicated symbolically by 25.
[0024] The invention is not limited to the above embodiment given
by way of example, and instead it can be modified within the scope
of the attached patent claims and the inventive concept.
* * * * *