U.S. patent application number 12/438683 was filed with the patent office on 2010-11-25 for dental superstructure, and a method of manufacturing thereof.
This patent application is currently assigned to Biomain AB. Invention is credited to Sture Benzon, Per Olof Leike.
Application Number | 20100297583 12/438683 |
Document ID | / |
Family ID | 41003393 |
Filed Date | 2010-11-25 |
United States Patent
Application |
20100297583 |
Kind Code |
A1 |
Benzon; Sture ; et
al. |
November 25, 2010 |
DENTAL SUPERSTRUCTURE, AND A METHOD OF MANUFACTURING THEREOF
Abstract
A dental superstructure, and a manufacturing method thereof,
comprising a screw-channel (1), through which screw-channel a screw
member is to be inserted, and a screw member seat (3), for
providing support to the head of said screw member during fixation
of said dental superstructure to a spacer element or an implant
(5), are provided. Said dental superstructure is provided with a
central axis of said screw-channel (1) and a central axis of said
second mouth (4) that at least partly do not coincide. A
manufacturing method thereof, a screw-member, and a screwdriver are
also provided.
Inventors: |
Benzon; Sture; (Helsingborg,
SE) ; Leike; Per Olof; (Billdal, SE) |
Correspondence
Address: |
MERCHANT & GOULD PC
P.O. BOX 2903
MINNEAPOLIS
MN
55402-0903
US
|
Assignee: |
Biomain AB
Helsingborg
SE
|
Family ID: |
41003393 |
Appl. No.: |
12/438683 |
Filed: |
August 22, 2007 |
PCT Filed: |
August 22, 2007 |
PCT NO: |
PCT/SE2007/050565 |
371 Date: |
August 10, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60919041 |
Mar 20, 2007 |
|
|
|
Current U.S.
Class: |
433/174 |
Current CPC
Class: |
A61C 8/0068 20130101;
A61C 8/0089 20130101; A61C 8/005 20130101; A61C 8/0048 20130101;
A61C 13/08 20130101; Y10T 408/03 20150115; A61C 8/0051 20130101;
Y10T 29/49567 20150115 |
Class at
Publication: |
433/174 |
International
Class: |
A61C 8/00 20060101
A61C008/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 25, 2006 |
SE |
SE 6061754-5 |
Claims
1. A dental superstructure comprising a screw-channel with a first
mouth, through which screw-channel a screw member is to be
inserted, and a screw member seat with a second mouth, for
providing support to the head of said screw member during fixation
of said dental superstructure to a spacer element or an implant
through said second mouth, whereby a communication is obtained
between said first mouth and said second mouth, wherein at least
one part of a central axis of said screw channel and a central axis
of said second mouth do not coincide.
2. The dental superstructure according to claim 1, wherein said
screw member seat is integrated with said dental
superstructure.
3. The dental superstructure according to claim 1, wherein
shoulders of said screw member seat has a declining shape.
4. The dental superstructure according to claim 1, wherein
shoulders of said screw member seat has an arched or semi-spherical
shape.
5. The dental superstructure according to claim 1, wherein said
superstructure is manufactured of a material selected from
titanium, zirconium oxide, alloys of titanium and zirconium.
6. A method of manufacturing of a dental superstructure comprising
a screw-channel with a first mouth, through which screw-channel a
screw member is to be inserted, and a screw member seat with a
second mouth, for providing support to the head of said screw
member during fixation of said dental superstructure to a spacer
element or an implant, whereby a communication is formed between
said first mouth and said second mouth, wherein drilling said
communication such that at least one part of a central axis of said
screw-channel and a central axis of said second mouth do not
coincide.
7. The method according to claim 6, wherein said drilling comprises
a drilling of a first straight bore from a first point, and a
drilling of a second straight bore from a second point, such that
said first bore and said second bore intersect in the interior of
said superstructure to form said communication.
8. The method according to claim 7, wherein the drilling of said
first bore and said second bore is done by a twist drill, whereby a
diameter suitable for constituting the threaded part of a screw
member is obtained.
9. The method according to claim 7, wherein said drilling comprises
a drilling of a third bore using said first bore and said second
bore as guides, said third bore being drilled by using a drill bit
with a cutting surface of a sufficient diameter to create said
screw-channel through which said screw member may be passed in
order to attach said dental superstructure to said spacer element
or said implant.
10. A screw-member, comprising a threaded part and a screw-head
with a recess for receiving a driving means, said screw-head
comprising a surface, bearing, in use, on shoulders of a
screw-member seat, wherein said surface is bevelled towards said
threaded part.
11. A screwdriver, comprising a rotatable handle portion and a
flexible shaft portion, with a distal end coupled to said handle
portion and a proximal end coupled to a tip for driving a screw
member with rotation transmitted from said rotatable handle
portion, wherein by said flexible shaft portion comprising a
plurality of wires, said wires being twinned in a plurality of
layers, such that said flexible shaft portion is formed between
said distal end and said proximal end.
12. A screwdriver according to claim 11, wherein one part of said
plurality of layers is twinned in one direction and another part of
said plurality of layers is twinned in another direction.
Description
FIELD OF THE INVENTION
[0001] This invention pertains in general to the field of a dental
superstructure and a manufacturing method of said superstructure.
More particularly the invention relates to a superstructure to be
connected to an osseointegrated dental implant. A superstructure of
this kind is disclosed in SE506850.
BACKGROUND OF THE INVENTION
[0002] The goal of a dental implant system is to restore the
patient to normal function, comfort, aesthetic, speech and health
regardless of the current oral condition. These implant systems are
based on the implantation of dental implants, such as dental
implants made of biocompatible titanium, through insertion into the
patient's jawbone. In this respect, the use of biocompatible
titanium started in Sweden as early as 1950, and has since then
been further developed and spread world-wide. During the 1980's a
number of implant systems entered the world market. Methods are
known in the art to attach a dental superstructure to an implant. A
couple of methods are based on the use of a screw member. Theses
screw members can attach the superstructure to the implant, either
directly or via spacers.
[0003] When implants are implanted in the mouth of a patient who
has been without teeth for some time problems arise due to
degeneration of bone. If a person has been without teeth for some
time, the jawbone that is not under strain of natural teeth or
implants, will dissolve and assimilate over time, yielding less
bone material for the proper anchoring of a dental implant. To find
enough bone for optimal implantation, the implant has to be angled
so that the general axis of the implant projects out of the mouth.
Fixing a superstructure with a screw member in a straight screw
channel to such implants necessitates that the mouth of the screw
channel may be forced to be placed on a visual surface of the
dental superstructure. Also, the optimum placement of the implant,
due to the present dental situation, often results in a non-optimum
placement of the dental superstructure in terms of the patient's
aesthetics, phonetics and bite.
[0004] Therefore, there is a need in the dental field for greater
freedom of placement of a dental implant in order to optimize the
stability and success of the implantation, while still achieving
good aesthetics, phonetics and bite of the patient.
[0005] Furthermore, in the above mentioned dental situation there
is a need to be able to use an implant placed optimally with regard
to the dental situation, that is, the anatomy of the jawbone, while
still allowing the dental superstructure to be applied in an
optimal way to said implant, such that the mouth of a screw channel
not is visible from outside the mouth of the patient.
[0006] The means already known in the art for achieving this goal
include the use of angled spacers and dental superstructures
attached to the implant with adhesive or with other techniques not
based on the use of a screw member. The angled spacers have many
drawbacks and are characterized by adding significant height to the
superstructure, multiple sources of errors, since the coordination
of multiple parts undoubtedly leads this, an unnecessarily high
price, as a result of the multiple parts and multiple manufacturing
steps, increased risk of bacteriological attack, due to the several
corners and surfaces exposable to this, weaker screw for the
attachment of the dental bridge, since no follow-up draft of said
screw is possible since a structure is applied on top of said
angled spacers. It also results in an increased complexity of the
attachment of the superstructure to the implant. U.S. Pat. No.
6,848,908 discloses an arrangement including an angled spacer
element of this kind, including a first passage and a second
passage. The first passage is operative to fasten said spacer
element in an implant, and the second passage is operative to
fasten a superstructure on said spacer element. Superstructures
attached to an implant without using a screw member results in less
strength, difficulties in detachment and also incompatibility
problems with commercially available implant systems of today.
[0007] Furthermore, U.S. Pat. No. 5,947,733 discloses a spacer
element with a non-linear bore, connecting a first mouth, intended
to be connected to a dental implant, and a second mouth, intended
to be connected to a dental superstructure through a screw member
engaging with the threaded part (132, 232, 332) of the spacer
element. Thus, also this system is in need of spacer elements at
least for solving the problem of guiding the mouth of a screw
channel, such that it is not visible from outside the mouth of the
patient.
[0008] There is therefore a need, among others, for a method of
attaching or detaching a dental superstructure to a dental implant
at a chosen angle without adding additional height to the chosen
superstructure.
[0009] Thus, there is a need for a new superstructure that may be
fastened to an implant without angled spacer elements or
superstructures attached to the implant with only adhesive or with
other techniques not based on the use of a screw member. There is
also need for a simpler, faster and cheaper production method of
dental superstructures, while still providing the benefits
according to above. Furthermore, there is a need to provide for the
possibility of a simple assembly ex situ (outside the patient's
mouth) and application in situ (in the patient's mouth).
[0010] Hence, an improved superstructure, and a manufacturing
method thereof, would be advantageous, and in particular a
superstructure, and a manufacturing method thereof, allowing for
the exclusion of angled spacer elements or fastening of a
superstructure to an implant by adhesives, without being forced to
place the mouth of the screw channel on a visual surface of the
dental superstructure would be advantageous.
SUMMARY OF THE INVENTION
[0011] Accordingly, the present invention seeks to mitigate,
alleviate or eliminate one or more of the above-identified
deficiencies and to provide an improved superstructure of the kind
referred to, and a manufacturing method thereof. For this purpose
the superstructure of this kind is characterized in that a central
axis of at least one part of a screw-channel and a central axis of
a mouth of a screw member seat do not coincide, and the
manufacturing method is characterized by drilling a first bore from
a first point of said superstructure, which first point is intended
to face an implant or spacer element, drilling a second bore from a
second point on said superstructure, which second point is intended
to provide a mouth of a screw channel for attaching said
superstructure to said spacer element or implant.
[0012] Advantageous features of the invention are defined in the
dependent claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] These and other aspects, features and advantages of which
the invention is capable of will be apparent and elucidated from
the following description of embodiments of the present invention,
reference being made to the accompanying drawings, in which
[0014] FIG. 1 illustrates a cross-section of an embodiment of a
superstructure according to the present invention.
DESCRIPTION OF EMBODIMENTS
[0015] The following description focuses on embodiments of the
present invention applicable to a superstructure, and also to a
method of manufacturing said superstructure.
[0016] The present invention discloses, according to FIG. 1, a
superstructure, and a manufacturing method thereof, comprising a
main body, comprising a screw-channel 1 with a first mouth 2,
through which screw-channel 1 a screw member is to be inserted, and
a screw member seat 3 with a second mouth 4, for providing support
to the head of said screw member during fixation of said dental
superstructure to a spacer element or an implant 5 through said
second mouth 4, whereby a communication is obtained between said
first and second mouth, wherein at least one part of a central axis
of said screw-channel 1 differs from a central axis of said second
mouth 4. In this way the mouth 2 of the screw channel 1 may be
located such that the superstructure may be attached/detached to a
dental implant or a spacer element 5 where the mouth 2 of the screw
channel 1 not is visible from outside the patients mouth.
[0017] In one embodiment of the manufacturing method of said
superstructure, a superstructure is first manufactured in a way
known to the skilled artisan, and then provided with a
communication according to above. Such a method is for example
disclosed in the Swedish patent SE 509,437, but other manufacturing
methods known to the skilled artisan, such as moulding etc., are
also within the scope of the present invention.
[0018] In one embodiment of the present invention the
superstructure is, in contrast to the manufacturing methods
according to the prior art, manufactured with integrated spacer
elements, milled from one single-piece blank, such that the dental
superstructure obtains a main body and spacer elements, wherein
said main body and said spacer elements are integrated. In this
context the term integrated means that the dental superstructure,
comprising a main body, and the spacer elements are consisting of
one piece of material, such that no interface is present in between
said superstructure and said spacer elements. In this
superstructure the dimensions of spacer elements can be varied in
accordance with the specific dental situation of a patient intended
to receive said replacement structure. When the superstructure is
applied the spacer elements will be cooperating with dental
implants, inserted and osseointegrated in bone tissue. To obtain a
perfect fit, i.e. no gap, between the superstructure and the gum
tissue, the length and angle, in respect of the jawbone,
superstructure, and jawbone, of the spacer elements will be
individual for each spacer in respective spacer position.
[0019] In one embodiment the material of said superstructure may be
selected from the group comprising titanium, zirconium oxide,
alloys of titanium and zirconium, and other biocompatible
materials, or combinations thereof.
[0020] When a superstructure, according to any of the embodiments
above, has been obtained, a superstructure wherein a central axis
of at least one part of a screw-channel differs from a central axis
of a mouth of a screw member seat is provided. In one embodiment
this is obtained, according to FIG. 2, by drilling a first straight
bore 21 from a first point 22 on a side of the dental
superstructure, at which first point 22 the mouth of the
screw-channel is to be placed, and a second straight bore 23 from a
second point 24 on the side of the dental superstructure intended
to face the implant or spacer element. It is of course possible to
drill the second bore 23 before the drilling of the first bore 21,
while still being inside the scope of the present invention. The
first and second bores are drilled such that they intersect in the
interior of the dental superstructure. Then a third bore 31 may be
drilled, according to FIG. 3, after the drilling of said first bore
21 and said second bore 23. This third bore may result in a
screw-channel. This third bore may be drilled using said first and
second bores as guides. Said third bore may be drilled by using a
drill bit with a cutting surface of a sufficient diameter to create
a bore through which a screw member may be passed in order to
attach the dental superstructure to a spacer element or an implant
5. The third bore 31, i.e. the screw-channel 1, may preferably be
drilled close to said second point 24, but not the whole way
through. Since the diameter of the third bore 31 is larger than the
diameter of said second bore 23, shoulders 32 will form in the
screw-channel 1. Said shoulders may then form the seat 3 for a
screw member head in the bottom of the screw-channel 1, while being
integrated with said superstructure. Thus, a threaded part of a
screw member inserted in the screw-channel may be passed through
said bore, i.e. said second bore 23, to subsequently attach the
dental superstructure to a spacer element or implant 5. Preferably,
the diameter of said second bore 23 corresponds to the diameter of
the threaded part of the screw member, whereby the screw member may
be passed through said bore to fixate the superstructure to an
implant or a spacer element 5. Thus, a dental superstructure
comprising a main body, comprising a screw-channel 1 with a first
mouth 2, through which screw-channel 1 a screw member is to be
inserted, and a screw member seat 3 with a second mouth 4, for
providing support to the head of said screw member during fixation
of said dental superstructure to a spacer element or an implant 5
through said second mouth 4, may be obtained. Hereby a
communication is obtained between said first mouth 2 and said
second mouth 4. By providing a central axis of at least a part of
said screw-channel 1 and a central axis of said second mouth 4 that
do not coincide, one may guide the position of said first mouth 2,
i.e. through which a screw member is to be inserted, into a
position that optimizes the arrangement of the superstructure. This
may for example be to locate said first mouth 2 in an aesthetically
pleasing position, such as on a surface of the superstructure that
can not be seen from outside the mouth of the patient. It is also
possible that only the direction of the central axis of a part of
the screw-channel 1 differs from the direction of the central axis
of the mouth 4 of the screw member seat 3, in accordance with FIG.
1, while still being inside the scope of the present invention.
[0021] In one embodiment of the present invention the central axis
of said first mouth 2 and the central axis of said second mouth 4
do not coincide.
[0022] In one embodiment the first bore 21 and the second bore 23
are made with a conventional twist drill. In this way the first
bore 21 and the second bore 23 are drilled to a diameter of a
suitable size for passing of the threaded part of a screw member,
which screw member is used for attaching the superstructure to a
spacer element or implant 5. It is also possible to drill said
second bore 23 using a drill bit with a cutting surface of a
sufficient diameter to create a bore through which a screw member
may be passed in order to attach the dental superstructure to a
spacer element or an implant.
[0023] It is also possible to drill said third bore all the way
through said first bore, in accordance with FIG. 4. Then a separate
seat 41 for the screw member head may subsequently be inserted and
attached to said superstructure. This may be done by attachment
techniques known in the art, such as welding or attachment by known
adhesive agents. It is even possible to only drill one bore, with a
diameter through which a screw member may be passed in order to
attach the dental superstructure to a spacer element or an implant.
This bore may extend all the way from said first point 22 to said
second point 24, or it may extend to a close proximity to said
second point 24. If said one bore extends all the way from said
first point 22 to said second point 24, a separate seat 41,
comprising a hole 42 for matching the threaded part of a suitable
screw member, for the screw member head may subsequently be
inserted and attached to said superstructure by attachment
techniques known in the art, such as welding or attachment by known
adhesive agents. If said one bore do not extend all the way from
said first point 22 to said second point 24, a bore, matching the
threaded part of the screw member, may be drilled from said first
point 24, i.e. the point intended to face the dental implant or a
spacer element 5, whereby the screw member seat 3 and the second
mouth 4 are created, according to the teachings above. By providing
a central axis of at least a part of said one bore and a central
axis of said bore, matching the threaded part of the screw-member,
or said hole, for matching the threaded part of a suitable
screw-member, that do not coincide, one may guide the position of a
mouth of said one bore, i.e. through which a screw member is to be
inserted, into a position that optimizes the arrangement of the
superstructure.
[0024] An example of a separate seat 41 may be a ring with an outer
diameter corresponding to the inner diameter of the screw-channel 1
of the superstructure, and an inner diameter corresponding to the
threaded part of the screw member, intended to be used when
fixating the superstructure to a spacer element or an implant
5.
[0025] In yet another embodiment of the present invention the
superstructure is provided with a dental implant seat or a spacer
element seat, such as a recess suitable for receiving a protrusion
on said dental implant or spacer element. It is of course also
possible to provide the superstructure with a protrusion and the
dental implant or spacer element with a recess, as long as the
seating effect is obtained. This dental implant seat or a spacer
element seat provides the advantage of easier assembling of the
superstructure on a dental implant or a spacer element.
[0026] In one embodiment of the present invention the drill bit
used, with a cutting surface of a sufficient diameter to create a
bore through which a screw member may be passed, i.e. a
screw-channel, such as the drill bit used when drilling said third
bore, may have a declining cutting surface, such as an arched,
semi-spherical, or spherical cutting surface. In this way the
bottom part of the screw-channel may have a declining shape, such
as an arched or semi-spherical. Thus, the bottom part may fit with
a screw member, according to FIG. 5, with a bevelled, such as
arched, spherical or semi-spherical head 51 and a threaded part 52.
Hereby, the diameter of the screw member head 51 may decline, in an
arched way, along with a surface 53 intended to, in use, bear upon
the shoulders of a screw member seat, from the diameter of the
screw member head 51 to approximately a diameter of a threaded part
52 of the screw member. A screw member with a bevelled, such as
arched, spherical or semi-spherical, head may also follow a
screw-channel 1 according to the invention. The arched, spherical,
or semi-spherical head of the screw member may in this way act as a
guide for guiding the screw member from the mouth 2 of
screw-channel, i.e. said first point 22, to a seat 3 in the bottom
of said screw-channel 1. This seat also comprises said second bore
23, through which the threaded part of the screw member may be
passed to attach said superstructure to a spacer element or implant
5. The screw member with a spherical or semi-spherical head 51 also
provides a higher fixing strength and self-centring properties.
Since the surface 53 bearing on the shoulders of the screw member
seat 3 is arched, such as spherical or semi-spherical, a greater
contact surface between the screw member and the shoulders 32 of
the screw member seat 3 is obtained. Thereby, the fixating strength
obtained from the fixation of the superstructure to the dental
implant 5 may be greater than if the surface bearing on the
shoulders of the screw member not was arched. The screw member is
provided with a recess for receiving a driving means, such as a
screwdriver. This recess may be a score, or a slit. The recess may
also have other shapes, corresponding to a screwdriver, such as a
starshape or a recess with a number of sides, such as tri-, tetra-,
penta-, or hexagonal. It is of course within the present invention
to provide such a recess in any other shapes corresponding to a
matching male part on a screwdriver or other driving means. Thus, a
screw-member, comprising a threaded part and a screw-head with a
recess for receiving a driving means, such as a screwdriver, said
screw-head comprising a surface bearing, in use, on shoulders of a
screw-member seat, wherein said surface is bevelled towards the
threaded part, has been described.
[0027] It is also within the present invention to drill said third
bore with drilled bits having cutting surfaces with other declining
and/or bevelled shapes, such as cone shaped.
[0028] The screw member may be fixed with a screwdriver, in
accordance with FIG. 6a, comprising a rotatable handle portion 61
and a flexible and/or bendable shaft portion 62, with a distal end
63 coupled to said handle portion 61 and a proximal end 64 coupled
to a tip 65 for driving said screw member with rotation transmitted
from said rotatable handle portion 61. Such a screwdriver, for
fastening screw members in a screw-channel described above, may
comprise a flexible and/or bendable shaft 62. This flexible shaft
62 may in one embodiment comprise twinned wires 66, giving a high
torque capacity, independent of shaft bending and angle to the
screw member. Said flexible shaft portion 62 may comprise a
plurality of wires 66, said wires being twinned in a plurality of
layers, in accordance with FIG. 6b, such that said flexible shaft
62 is formed between said distal end 63 and said proximal end 64.
The plurality of layers may be twinned such that one part of the
layers is twinned in one direction while the other part of the
layers is twinned in the other direction. Since said screwdriver
has twinned layers of wires, in accordance with FIG. 6b, in two
directions the screwdriver is provided with torque capacity in both
rotational directions of said flexible shaft. In one embodiment the
number of twinned layers may be uneven, whereby the uneven number
of layers are twinned in a direction giving the screwdriver a
unfastening torque capacity while the even number of layers are
twinned in a direction giving the screwdriver a fastening torque
capacity. The number of layers may for example be selected within
the interval of 2 to 30, such as 10 to 20, but this interval is
only intended to be interpreted as guidance and not as limiting. Of
course, it is possible to construct screwdrivers with a number of
twinned layers outside the given interval, which still may obtain
the intended effect. The torque capacity of such a screwdriver may
be at least 30 to 35 Ncm.
[0029] In one embodiment the screwdriver is provided with a
flexible and/or bendable core, in accordance with FIG. 6c, in said
shaft, onto which the plurality of wires are twinned. This flexible
and/or bendable core may for example be manufactured of an ordinary
plastics or rubber, fulfilling the desired features according to
flexing and/or bending in respect of being able to flexate or bend
in the screw channel.
[0030] In one embodiment the rotatable handle portion 61 and a
flexible and/or bendable shaft portion 62 of the screwdriver are
separable. In this embodiment the flexible and/or bendable shaft
portion 62 may first be inserted in the screw-channel 1, and
thereafter the rotatable handle portion 61 is mounted and fixed to
said flexible and/or bendable shaft portion 62. Thereby, it may be
easier to access the screw member in the screw-channel 1, if the
central axis of the screw-channel and the central axis of the
second mouth differs in a high degree.
[0031] The elements and components of an embodiment of the
invention may be physically, functionally and logically implemented
in any suitable way. Indeed, the functionality may be implemented
in a single unit, in a plurality of units or as part of other
functional units. As such, the invention may be implemented in a
single unit, or may be physically and functionally distributed
between different units and processors.
[0032] Although the present invention has been described above with
reference to specific illustrative embodiments, it is not intended
to be limited to the specific form set forth herein. Rather, the
invention is limited only by the accompanying claims and other
embodiments than the specific above are equally possible within the
scope of these appended claims.
[0033] In the claims, the term "comprises/comprising" does not
exclude the presence of other elements or steps. Furthermore,
although individually listed, a plurality of means, elements or
method steps may be implemented by e.g. a single unit or processor.
Additionally, although individual features may be included in
different claims, these may possibly advantageously be combined,
and the inclusion in different claims does not imply that a
combination of features is not feasible and/or advantageous. In
addition, singular references do not exclude a plurality. The terms
"a", "an", "first", "second" etc do not preclude a plurality.
Reference signs in the claims are provided merely as a clarifying
example and shall not be construed as limiting the scope of the
claims in any way.
* * * * *