Note: Descriptions are shown in the official language in which they were submitted.
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DENTAL SYSTEM
Field of the Invention
This invention pertains in general to the field of a
dental system for determining an angle in a dental
superstructure comprising a non-linear screw-channel.
Background of the Invention
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.
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
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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.
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.
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.
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. US 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
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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.
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.
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).
Moreover, there is a need to improve the conversion
from a patient specific dental model, made by a dental
technician or dental surgeon, into a final superstructure
to be connected to an osseointegrated dental implant.
Hence, an dental system for aiding the manufacturing
of an improved superstructure, would be advantageous, and
in particular a superstructure 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.
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Summary of the Invention
Accordingly, the present invention seeks to mitigate,
alleviate or eliminate one or more of the above-identified
deficiencies and to provide a dental system, a bore angle
member, a bore angle connector, and a distance member of
the kind referred to, and a manufacturing method thereof.
For this purpose a dental system is provided for
determining a suitable angle for a dental superstructure
with a non-linear screw-channel, said system comprising a
bore angle member, comprising a head portion, said bore
angle member being configured to be mounted on a dental
implant, and a bore angle connector having a bottom portion
for connection to said head portion of said bore angle
member, whereby said bore angle member and said bore angle
connector are pivotably connected to each other, and a bore
angle member is provided, configured to be mounted on a
dental implant, said bore angle member comprising a head
portion configured to be pivotably connected to a bore
angle connector, and a bore angle connector is provided,
comprising a main portion and a bottom portion, said bottom
portion being configured to be pivotably connected to a
bore angle member, and a distance member is provided,
configured to be connected to a bore angle member or a bore
angle connector, such that the pivoting angle between said
bore angle member and said bore angle connector is limited.
Advantageous features of the invention are defined in
the dependent claims.
Brief Description of the Drawings
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
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Fig. 1 is an illustration showing a cross-section of
a superstructure according to an embodiment;
Fig. 2 is an illustration showing a cross-section of
a superstructure according to an embodiment;
5 Fig. 3 is an illustration showing a cross-section of
a superstructure according to an embodiment;
Fig. 4 is schematic cross-section view of a bore
angle screw according to an embodiment;
Fig. 5 is schematic cross-section view of a bore
angle connector according to an embodiment;
Fig. 6 is schematic cross-section view of a bore
angle screw according to an embodiment;
Fig. 7 is schematic cross-section view of a bore
angle connector according to an embodiment;
Fig. 8a is schematic cross-section view of a distance
member according to an embodiment;
Fig. 8b is schematic cross-section view of a distance
member according to an embodiment;
Fig. 9a is schematic cross-section view of an system
according to an embodiment;
Fig. 9b is schematic cross-section view of an system
according to an embodiment;
Fig. l0a is schematic cross-section view of bore
angle connector according to an embodiment;
Fig. lOb is schematic cross-section view of bore
angle connector according to an embodiment;
Fig. 11 is schematic cross-section view of an
arrangement according to an embodiment; and
Fig. 12 is schematic cross-section view of an
arrangement according to an embodiment.
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Description of embodiments
The following description focuses on embodiments of
the present invention applicable to a superstructure, and
also to a method of manufacturing said superstructure.
The present invention discloses, according to Fig. 1,
a 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, 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. Such a superstructure will herein be
referred to as a superstructure with a non-linear screw-
channel. Arrangements of non-linear screw-channels and how
these may be configured in superstructures in respect of
dental implants are also shown in Fig. 11 and 12.
There is a need for a system or device for
determining the angle(s) between the central axis of said
first mouth 2 and the central axis of the second mouth 4.
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.
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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.
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.
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
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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
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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.
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.
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.
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
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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
5 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.
Before a dental superstructure may be manufactured a
dental technician and/or dental surgeon may build up a
10 dental model based on the specific dental situation of a
patient. A bite template of the patient mouth anatomy, made
of e.g. wax, may be used for this purpose. The bite
template is produce by placing a material, such as wax, in
the mouth of the patient having dental implants, and
letting the patient bite the material, and thus an exact
reproduction of the patient specific dental status is
obtained. The bite template thus contains information about
the positions of the dental implants. The bite template may
then be used to create a dental model of the specific
patient. The dental technician and/or dental surgeon then
refines the dental model in respect of bore angles etc.,
such that e.g. the mouth of a screw channel not is visible
from outside the mouth of the patient. The final dental
model thus reflects the desired final result.
A difficulty of manufacturing the superstructure with
a non-linear screw-channel has been to translate the dental
model information, such as information regarding the bore
angles to an apparatus with capability of manufacturing the
superstructure. In order for the superstructure to
perfectly match the dental model, the bore angles may be
fixated in the dental model before the manufacturing of the
superstructure proceeds.
In an embodiment a bore angle member, such as a bore
angle screw, according to Fig. 4, is provided. This bore
angle screw comprises a head portion 41, and a screw member
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portion 42. The head portion 41 may have a spherical or
semi-spherical shape. In the top of the head portion 41, a
screw recess 43 is provided, such that the screw member 42
of the bore angle screw may be screwed into e.g. a dental
implant by means of a screwdriver having the corresponding
inverted shape of the screw recess. In an embodiment the
screw recess has the shape of a hexagon. Different sizes of
the screw member 42 may of course be used without departing
from the scope of the present invention.
In an embodiment a bore angle connector 51, according
to Fig. 5, is provided. The bore angle connector may have a
bottom portion 52 that precisely fit the shape of the bore
angle head portion 41. For example, if the bore angle screw
head portion is spherical with a specific diameter, the
bottom portion 52 may have the corresponding spherical
diameter. Moreover the bore angle connector has a main
portion 53. This main portion 53 may resemble the shape and
size of the bore that will be made for each dental implant
in the resulting manufactured superstructure.
In another embodiment the bore angle connector bottom
portion 52 is concavely shaped to receive the bore angle
screw head portion 41, with the same diameter, however the
bottom portion inlet area of the bore angle connector 52 is
slightly smaller than the head portion 41 of bore angle
screw. This means that the bore angle connector 52 may me
pressed over the bore angle screw head portion 41, by
expansion of the connector material, to become securely
connected. This may for example be accomplished if the bore
angle connector is manufactured of a resilient material,
such as a plastic material. Thus, the bore angle screw may
be mounted on an implant, in the mouth of a patient or in a
mould corresponding to the dental situation of a patient. A
bore angle connector may then be mounted, such as snapped
onto, the bore angle screw. Then, the bore angle connector
may be pivoted into a position that corresponds to a
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position of a first mouth 2 of the superstructure intended
to be manufactured by the aid of the system, said system
comprising said bore angle screw and said bore angle
connector, such that said first mouth 2 will be located in
a suitable position on said superstructure that will not be
visible from the outside of a mouth of a patient. This
angle may then be fixed and/or measured, and the
manufacturer of the superstructure will know where to
position said first and second mouth on said
superstructure. Thereby, the angle between the bore angle
screw and the bore angle connector will correspond to the
angle between a central axis between said first mouth 2 and
a second mouth 4, at a screw member seat 3. A suitable
position will be a position possible on the dental system
used in case referred to, whereby a suitable screw member
seat will be formed in the screw channel.
In an embodiment the bore angle connector bottom
portion 52 is slotted, such that the bottom portion 52 may
be pressed over the head portion of the bore angle screw,
to snap or click around the bore angle screw head portion,
in order to become more fixated. This may for example be
accomplished if the bore angle connector is manufactured of
a resilient material, such as a plastic material.
When the bore angle connector 51 is connected or
pressed on the bore angle screw head portion 41, it may be
pivoted, such as rotated, in the same way as a ball joint,
if the head portion 41 is of a spherical or semi-spherical
shape. A degree of friction may be provided that makes
interconnection between the bore angle connector bottom
portion 52 and the screw head portion 41 suitable for
remaining in one angle position, such that it requires a
fair amount of force, e.g. applied by hand, to pivot, such
as rotate, the bore angle connector 51 around the bore
angle screw head 41. The friction coefficient may be varied
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using different materials of the bore angle connector 51,
and the bore angle head portion 41.
In one embodiment the interconnection between the
bore angle connector bottom portion 52 and the screw head
portion 41 may be such that the bore angle connector may be
rotated into such an angle that the screw recess 43 may be
reached, i.e. that the bore angle connector bottom portion
52 does not cover the screw recess. In this way the bore
angle head portion 41 and the bore angle connector bottom
portion 52 may be interconnected during the obtainment of
information regarding angles and positions.
In still one embodiment the bore angle head portion
has a flat circular shape. The bore angle connector may in
this embodiment have a corresponding bottom portion, e.g.
such that the circular shape fits into a recess in the
bottom portion of the bore angle connector. The recess may
be angled such that the bore angle connector may only be
rotated in the plane of the recess, and accordingly in the
plane of the circular shape.
In an embodiment the head portion of the bore angle
screw is attachable/detachable from the bore angle screw.
By utilizing this embodiment, various head portions of
different shapes may be selected, having different shapes
for reducing the degree of rotation from three dimensions
to two dimensions or even one dimension. In a practical
implementation the dental technician and or dental surgeon
may first, attach the bore angle screw into the dental
implant of the dental model. Subsequently, the
attachable/detachable head portion is removed and is
replaced by a new head portion. A bore angle connector
having a bottom portion corresponding to the
attachable/detachable head portion of the bore angle screw
is then connected to the attached head portion. Using the
attachable/detachable bore angle screw head portion and
corresponding bore angle connector bottom portion will
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reduce the degree of rotation, and thus bore angle, to two
or one dimensions. An advantage of this embodiment is that
as the degree of rotation is reduced for the bore angle
connectors, the final dental model will be more robust and
insensitive to outer conditions that might influence the
bore angles, e.g. unintended applied forces on the dental
model during transport to the manufacturer that otherwise
might have changed the bore angles of the dental model.
The shape of the head portion of the bore angle screw
and the corresponding bore angle connector shape may be any
shape providing a means for rotation of the bore angle
connector in respect the bore angle screw.
In an embodiment, according to Fig. 6, the bore angle
screw head portion 61 has the same shape as the bottom
portion 52 of the bore angle connector according to Fig. 5.
Thus, to be able to connect said screw head portion 61 with
the bottom portion of the bore angle connector, the bore
angle connector bottom portion 72 has the same shape as the
head portion 41 of the bore angle screw according to Fig.
4. This is illustrated in Fig. 7.
In an embodiment, according to Fig. 8a, a distance
member 80 is provided. The distance member 80 may in use be
placed between the implant and bore angle screw head
portion. In one embodiment, according to Fig. 8a, this
distance member 80 is configured such that it
circumferences the bore angle screw. This may for example
be obtained by configure this distance member in the form
of a ring. This ring may be threaded to fit with the
threaded part of the screw member 42. In this way this
distance member 80 may be screwed passed the threaded part
of the screw member 42, to thereafter fit with the
unthreaded part of the screw member 42. The function of the
distance member 80 is to limit the angle of freedom of the
bore angle connector 51 that is connected to the bore angle
head portion 41. This limitation is enabled, as the bore
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angle connector at a certain angle, with reference to the
bore angle screw length, will contact the distance member
making it impossible to achieve a greater angle between the
bore angle screw and the bore angle connector.
5 In an embodiment, according to Fig 8b, the distance
member 80 may be placed between the head portion of the
bore angle screw and the dental implant without the need of
being screwed through the threaded part of the bore angle
screw. The design of distance member may be suitable for
10 attaching the distance member around the main portion of
the bore angle screw. By attaching is meant that the
distance member 80, e.g. in the form of a ring having at
least the same diameter as the main body of the bore angle
screw, and provided with an opening 81. The opening 81
15 enables the distance member to be pushed around the bore
angle screw main portion, i.e the part of the bore angle
screw being located between the head portion 41 and the
screw member portion 42.
In respect of Figs. 6 and 7, the distance member may
instead be placed on, or integrated with, the bore angle
connector, to thereby provide the limitation of freedom of
the pivoting of the bore angle connector in respect of the
bore angle screw.
Fig. 9a and 9b illustrates two setups of said
distance member for limiting the angle of freedom of the
bore angle connector 91. In Fig. 7a a distance member 92a
with a height x is provided around a bore angle screw 93,
which is screwed into a dental implant 94. The bore angle
connector 91 is attached to the bore angle screw head
portion 95. The possible angle between the bore angle
connector and the bore angle screw, as the distance member
is placed between the dental implant and the bore angle
screw is indicated as y. In Fig. 7b a distance member 92b
with the height 2x is provided between the head portion and
dental implant. This corresponds to a maximal angle of z.
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As may be observed from Figs. 9a and 9b, by increasing the
height of the distance member the possible angle between
the connector and the bore angle screw is decreased, and
vice versa.
In an embodiment the centre of the head portion of
the bore screw angle determines the position of the screw
member seat in the superstructure. In this way a sufficient
distance is created from the screw member seat, such as the
screw member seat 3, and the second mouth, such as the
second mouth 4, of the screw channel 1, to provide a
fixating effect when a screw member is screwed through said
second mouth into a dental implant or a spacer element.
In an embodiment the distance member corresponds to
the maximum bore angle for the dental system used. There
are several dental systems commercially available, each
utilizing different dental implants etc. The distance
member hence determines a specific maximum bore angle for
each dental system and/or dental implant. In this way a
dental technician and/or a dentist may apply distance
members on the unthreaded part of the screw member 42,
which distance members certifies that the maximum angle of
the chosen dental system not is exceeded.
It is also possible to integrate a distance member on
the unthreaded part of the screw member 42. Thus, a set of
screw members 42 may only be used when a dental system
accepting screw channel angles lesser than the angle that
may be obtained by the interaction between the bore angle
screw, comprising a head portion, such as a head portion
41, and an integrated distance member, and a screw member
portion, such as a screw member portion 42, and a bore
angle connector, such as a bore angle connector 51, when
the bore angle connecter is angled until the bottom
portion, such as the bottom portion 52, reaches, and
thereby stops at, the distance member 80.
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In a practical implementation, the dental technician
and/or dental surgeon provides the dental model implants
with one bore angle screw each. Then a bore angle connector
is connected to each bore angle screw. The dental
technician and/or dental surgeon then modify the desired
bore angle for each implant by rotating the bore angle
connector into a desired angle. When the dental technician
and /or dental surgeon is satisfied with the bore angle
orientation a distance member according to an embodiment
may be positioned between each bore angle screw head
portion and the dental implant. By adjusting the height of
the distance member, the desired angle may be achieved with
high precision. After a distance member, giving the desired
angle between the bore angle connector and the bore angle
screw, is placed between the head portion and the bore
angle connector, the connector is fixated to the dental
implant, e.g. by means of fixating wax, plastic, tape, glue
or any other fixating means. In this manner the remaining
dental implants of the model is processed. The end result
will be a dental model having bore angle connectors with
fixated angles to the dental implant length axis for each
dental implant that requires bores with an angle. The
dental model may then be sent to a manufacturer for
manufacturing a superstructure for the patient specific
dental model.
Throughout the dental modelling, made by the dental
technician and/or dental surgeon, the distance between the
bore angle screw head and the dental implant will be fix as
the bore angle screw has the same length and will be
screwed into the implant completely.
In an embodiment, according to Fig. l0a and lOb, a
cylindrical cavity 101 is provided within the bore angle
connector 51, extending from the end of the main portion 53
towards the end of the bottom portion 52. The cylindrical
cavity 101 may be located in the centre of the bore angle
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connector 102 as indicated in Fig. l0a and Fig lOb. In Fig
l0a the cylindrical cavity extends from the end of the main
portion 53 towards the bottom portion end 52, with a length
smaller than the total bore angle connector length. In Fig.
lOb the cylindrical cavity extends throughout the total
bore angel connector. The cylindrical cavity may be used to
precisely determine the position and angle of the bores in
the manufacturing of the final superstructure.
In an embodiment the cylindrical cavity of the bore
angle connector, e.g. each bore angle connector of the
refined dental model as mentioned above, is provided with
an extended structure, such as a cylindrical structure
fitting in the cylindrical cavity. To precisely determine
the bore angle in three dimensions as well as the exact
position of each dental implant, a photo scanner may be
used to image the dental model. The information regarding
the bore angles and the implant positions are then used in
manufacturing the superstructure.
In an embodiment the extended structure has a
predetermined length and a predetermined end shape, such as
a circular shape. In this way it only requires one image
from one camera direction to obtain all bore angles and
dental implant positions of the dental model. In this
respect the Swedish patent application SE 0602116-6 is
hereby integrated in its entirety herein as reference.
The dental model comprising the extended structure(s)
may then be scanned with a photo scanner in three
dimensions such that the bore angle and exact position of
the dental implant may be obtained for the entire dental
model. This may be performed by inserting a cylindrical or
other structure fitting the cylindrical cavity of each bore
angle connector and subsequently image the cylindrical
structures to determine the exact bore angle for each
dental implant of the dental model in three dimensions, as
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well as the position of the dental implant using the
knowledge of the bore angle screw head portion location.
The different members of the present invention, i.e.
the bore angle screw, the bore angle connector, and the
distance member, may be manufactured of any suitable
material or combinations of suitable materials. These
materials may for example be metals, plastic materials etc.
Such metals may for example be stainless steels, aluminum,
titanium etc. It is thus possible to manufacture the bore
angle screw of a suitable metal, such as a stainless steel,
the bottom portion of the bore angle connector of a plastic
material, the main portion of the bore angle connector of a
metal, such as a stainless steel, and the distance member
of a metal, such as a stainless steel. In an embodiment the
bore angle screw is made of plastic material.
In another embodiment the bottom portion of the bore
angle connector 52 is made of a suitable metal, such as
stainless steel or aluminum.
In an embodiment a tooth set-up may be mounted on the
system comprising the bore angle screw(s), the bore angle
connector(s), and the distance member(s). This mounting may
be accomplished by fixating with wax or plastic material.
Thereafter, the tooth set-up may be disconnected from said
bore angle screw(s) by snapping of the connector(s) there
from, while still being connected to said bore angle
connector(s). The angle or angles between said bore angle
screw(s) and said bore angle connector(s) may be determined
before or after the mounting of the tooth set-up on said
system. When the tooth set-up with attached connector(s)
has been disconnected from said bore angle screw(s), the
tooth set-up with attached connector(s) may be sent to the
dentist, dental surgeon, or dental technician. The tooth
set-up with attached connectors may be sent to the dentist
together with the bore angle screws, or the dentist, dental
surgeon, or dental technician may have an own set of bore
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angle screws. Thereby, the dentist, dental surgeon, or
dental technician may reconnect the tooth set-up with
attached connector(s) to the bore angle screw(s), when the
bore angle screw(s) have been attached to the dental
5 implant(s), whereby the angles for the bore channels and
the location of the mouths of the bore channels may be
provided to thereby manufacture a fitting superstructure.
Depending on the type of dental implant and dental
status of the patient, the final bore angles may vary in
10 the dental model, created by the dental technician and/or
dental surgeon.
The application of the tooth set-up may be performed
both before and after the refinement of the bore angle,
made by the dental technician and/or dental surgeon. In an
15 embodiment the bore angle of each implant may be refined in
correspondence with the applied tooth set-up, giving a
specific bore angle for each dental implant. Hence, in this
embodiment the bore angle may differ for each dental
implants of the dental model. In another embodiment the
20 dental technician and/or dental surgeon applies, and
refines the tooth set-up based on the maximum bore angle
for each implant of the dental model. In this embodiment
the bore angle may differ for each dental implant of the
dental model. Hence, in this embodiment the bore angle is
maximal for each dental implant in reference to the bore
angle screw.
In yet another embodiment a combination of
specifically set bore angles and the maximum bore angles
for each implant may be used to precisely apply the tooth
set-up.
The present invention provides solutions that
facilitates in the dental modeling and the manufacturing of
a dental superstructure.
Advantages of the present invention are various.
Using the invention according to some embodiments, the
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dental model of the specific patient is facilitated and the
end result is easier to predict, e.g. by using a tooth set-
up in conjunction with the bore angle screw and bore angle
screw connector. Moreover, using the present invention
according to some embodiments, the bore angles and position
of the implants may be exactly reproduced in the
manufactured dental superstructure, and hence the present
invention solves the problem of converting the bore angles
defined by the dental technician and /or dental surgeon
precisely to be able to create a dental superstructure.
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.
In an embodiment a graphical user interface is
provided. The graphical user interface may be used as a
computerized dental modeling tool by the dental surgeon or
dental technician. The graphical user interface may be
provided with a number of windows, each representing e.g.
an observation plane, or 3D model. The graphical user
interface is configured to enable virtual 3D dental
modeling and is capable of creating or optionally
retrieving a virtual dental model comprising the jaw
structure of the patient. Optionally, if the dental
implants are already attached to the patient jaw structure,
also their respective position may be comprised in the
virtual model. The virtual dental model may be acquired
using a photo scanner as mentioned above or in any other
known technique 3D scanning. By 3D scanning is meant
acquiring a set of 2D images followed by performing image
analysis to be able to create a 3D model. In some
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embodiments the graphical user interface is configured to
create a 3D dental model of a set of acquired 2D dental
images. Once the 3D dental model is acquired and loaded
into the graphical user interface, the user is able to
virtually attach bore angle screws, distance members, bore
angle connectors to each of the dental implants comprised
in the virtual dental model. Moreover, the user may
interactively change each of the bore angles of each dental
implant in a suitable way, e.g. by using a pointing device,
such as a mouse or keyboard. This may optionally be
performed in each of three perpendicular planes or in a
visualized 3D model directly. In some embodiments the
graphical user interface comprises Computer Aided Design
(CAD) or Computer Aided Manufacturing (CAM) software to
facilitate modification of the virtual dental model and for
manufacturing of the final, finalized virtual dental model.
In some embodiments the bore angles may be defined
statically using the keyboard by setting the desired degree
values using any suitable coordinate system, such as
Cartesian coordinates, polar coordinates, etc. In some
embodiments the graphical user interface is configured to
generate a virtual superstructure based on the user-defined
components, such as bore angles, of the dental implant.
Thus, during generation of the superstructure parameters
such as bore angle, dental implant position, is taken into
account by the superstructure generating code segment. In
some embodiments a "generate superstructure" button is
provided in at least one window of the graphical user
interface to generate the superstructure. In some
embodiments the virtual superstructure may be provided with
a virtual teeth row. This particularly advantageous as it
enables the dental surgeon or dental technician to observe
the final result virtually and to be able to re-modify the
dental model until a perfect fit is achieved. Once the user
dental surgeon or dental technician is satisfied with the
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virtual dental model, a detailed specification of the
virtual superstructure may be printed out. Optionally, by
using incorporated CAM software, an exact true model of the
virtual superstructure may be manufactured. This provides
for a cheap and effective way of creating a superstructure
to a dental model.
Thus, according to one embodiment of the present
invention, a virtual dental system for determining a
suitable angle for a dental superstructure with a non-
linear screw-channel is provided, said system comprising a
virtual bore angle member, comprising a head portion, said
bore angle member being configured to be mounted on a
dental implant, and a virtual bore angle connector having a
bottom portion for connection to said head portion of said
bore angle member, whereby said bore angle member and said
bore angle connector are pivotably connected to each other,
wherein said virtual dental system, virtual bore angle
member, and virtual bore angle connector are configured to
be used in a computerized dental modeling software. It is
also possible to provide this virtual dental system with a
virtual distance member, according to above, limiting the
freedom of angle between said virtual bore angle member and
said virtual bore angle connector.
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.
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
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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.
