U.S. patent application number 12/637373 was filed with the patent office on 2010-04-15 for method for manufacturing a suprastructure and a corresponding drill jig.
This patent application is currently assigned to DENTAL VISION B.V.B. Invention is credited to Rene DE CLERCK.
Application Number | 20100092911 12/637373 |
Document ID | / |
Family ID | 3897052 |
Filed Date | 2010-04-15 |
United States Patent
Application |
20100092911 |
Kind Code |
A1 |
DE CLERCK; Rene |
April 15, 2010 |
METHOD FOR MANUFACTURING A SUPRASTRUCTURE AND A CORRESPONDING DRILL
JIG
Abstract
The invention concerns a method for manufacturing a
suprastructure (7) with artificial teeth (8) which is mounted on at
least one implant (9,10) that is provided in the cavity of the
mouth of a person and that has to be fixed to the bone of the lower
jaw or the upper jaw (1), whereby a drill jig (3) is manufactured
with at least one opening (4) for performing a boring (5) in the
bone for mounting said implant (9,10), with the feature that the
position of said opening (4) in the drill jig (3) and the position
of the latter is determined in relation to at least one reference
organ (2) that is fixed to said bone.
Inventors: |
DE CLERCK; Rene; (Tervuren,
BE) |
Correspondence
Address: |
BROWDY AND NEIMARK, P.L.L.C.;624 NINTH STREET, NW
SUITE 300
WASHINGTON
DC
20001-5303
US
|
Assignee: |
DENTAL VISION B.V.B
Tervuren
BE
|
Family ID: |
3897052 |
Appl. No.: |
12/637373 |
Filed: |
December 14, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10482927 |
Aug 23, 2004 |
7632097 |
|
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PCT/BE02/00117 |
Jul 8, 2002 |
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12637373 |
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Current U.S.
Class: |
433/75 |
Current CPC
Class: |
A61C 1/084 20130101;
B33Y 80/00 20141201 |
Class at
Publication: |
433/75 |
International
Class: |
A61C 3/00 20060101
A61C003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 6, 2001 |
BE |
2001/0463 |
Claims
1. An aligning plate adapted to fit within the mouth of a person,
comprising at least one circular aperture (4), positioned for
drilling a hole (5) in the bone of a lower or an upper jaw (1) of
the person, in order to place at least one implant (9,10), wherein
a diameter and an orientation of the aperture (4) corresponds to
that of the implant (9,10), wherein said aligning plate has fixing
means for fixing the aligning plate to at least one reference
element (2) that is provided in the bone, the fixing means forming
means for selecting the position of the aperture (4) relative to
the reference element to permit the hole (5) to be drilled in the
jaw (1), which hole corresponds to a desired position of the
implant (9,10) relative to the reference element (2) so that
critical anatomical structures are not touched during drilling.
2. The aligning plate according to claim 1, wherein the means has
an opening that connects up in a substantially exact fit with the
reference element (2).
3. The aligning plate according to claim 2, wherein said aligning
plate is detachably fixed to the reference element (2) by at least
one screw (14) or bolt.
4. The aligning plate according to claim 1, wherein a diameter of
the abovementioned aperture (4) is selected so that at least one
bush can be placed for drilling the hole (5) in said aperture (4),
in order to guide a drill for drilling the hole (5).
5. An aligning plate adapted to fit within the mouth of a person,
the aligning plate produced according to the method of claim 1 and
comprising: at least one circular aperture (4), positioned for
drilling a hole (5) in the bone of a lower or an upper jaw (1) of
the person, in order to place at least one implant (9,10), wherein
a diameter and an orientation of the aperture (4) corresponds to
that of the implant (9,10), wherein said aligning plate has fixing
means for fixing the aligning plate to at least one reference
element (2) that is provided in the bone, the position of the
aperture (4) relative to the fixing means being selected and
provided in such a way that it permits the hole (5) to be drilled
in the jaw (1), which hole corresponds to a desired position of the
implant (9,10) relative to the reference element (2) so that
critical anatomical structures are not touched during drilling.
Description
[0001] The invention relates to a method for producing a
superstructure provided with artificial teeth, which superstructure
is fitted on at least one implant, which is provided in the oral
cavity of a person and has to be fixed in the bone of a lower or an
upper jaw, an aligning plate with at least one aperture being
produced for the purpose of drilling a hole in the bone through
said aperture, in order to fit the abovementioned implant.
[0002] The method used according to the prior art for producing
such a superstructure is very laborious and protracted for a
patient. In a first step, a wax model of a dental prosthesis is
made using an impression that is taken of the patient's jaw. A
replica of this wax model is then prepared in synthetic resin, in
which replica openings are already provided, corresponding to a
possible position for the implants, for the purpose of drilling
holes in the jaw. A so-called CT scan then has to be made of this
replica when it has been placed on the corresponding jaw of the
patient, in order to determine the anatomical bone structure and
the precise location of nerve bundles and blood vessels. In this
way it is checked whether the drilling of holes for the implants is
possible, taking into account the anatomical structure of the jaw,
such as, inter alia, the position of nerve bundles or blood vessels
present there. If it is found that the proposed position of the
implants is unsuitable because, for example, nerve bundles or blood
vessels would be touched during the drilling of holes, a new or an
adapted model has to be produced.
[0003] In a subsequent step, an aligning plate is then produced on
the basis of the abovementioned replica, and the implants are
placed in position. When these implants have been placed and the
gums and the bone have healed after this surgical procedure, a
number of impressions of the jaw together with the implants are
taken, in order to produce a provisional model, i.e. a wax model,
of the superstructure. This provisional model then has to be fitted
on the patient. If the provisional model is satisfactory, the final
superstructure is produced on the basis of this provisional
model.
[0004] In a variant of the above method, the abovementioned first
step is to make a CT scan of the jaw on which the superstructure is
to be fixed, and an aligning plate is produced directly, on the
basis of the electronic information from this CT scan. The
superstructure is then further produced according to the technique
described above.
[0005] Owing to the different steps required in the case of these
processes, a patient generally undergoes six months of treatment
before a final superstructure is fitted.
[0006] Another method according to the prior art makes use of
prefabricated to superstructures. However, a disadvantage of this
method is that for fitting of the superstructure part of the bone
of the upper jaw or of the lower jaw has to be removed.
Furthermore, the prostheses placed in this way are not adapted to
the individual shape of a person's jaw.
[0007] The object of the invention is to overcome the
abovementioned disadvantages by proposing a method that allows
holes that are necessary for the placing of implants to be drilled
in a very simple and accurate manner. This method has the further
advantage that the production of a superstructure and its fitting
on a person's jaw can be performed in a very short time.
[0008] To this end, at least one reference element is fixed to the
abovementioned bone, and the location of anatomical structures of
the abovementioned jaw relative to this reference element is then
determined, means being provided on the abovementioned aligning
plate for fixing the latter on the abovementioned jaw relative to
the abovementioned reference element and, taking into account the
determined location of the anatomical structures, the position of
the abovementioned aperture in the aligning plate is determined in
such a way that critical anatomical structures, such as nerve
bundles or blood vessels, are not touched during the drilling of
the abovementioned hole when the aligning plate has been fixed on
the abovementioned jaw.
[0009] A screw is expediently fixed in the abovementioned bone,
said screw forming the abovementioned reference element.
[0010] According to a special embodiment of the method according to
the invention, means are provided on the abovementioned aligning
plate for fixing the latter detachably on the abovementioned
reference element before the abovementioned hole is drilled in the
bone. More particularly, the abovementioned means are formed by
providing an opening in the aligning plate, which opening connects
up in a virtually exact fit with the abovementioned reference
element.
[0011] According to a preferred embodiment of the method according
to the invention, a dental impression is made of the abovementioned
jaw with the abovementioned reference element, and a provisional
model of the abovementioned superstructure with teeth is made on
the basis of this impression, a three-dimensional image being made
of the abovementioned jaw together with this provisional model and
the abovementioned reference element.
[0012] In an advantageous manner, the abovementioned aligning plate
is made on the basis of the abovementioned three-dimensional
image.
[0013] The abovementioned three-dimensional image is preferably
processed electronically in order to produce the abovementioned
aligning plate and/or the abovementioned superstructure by means of
a so-called rapid prototyping technique.
[0014] According to an advantageous embodiment of the method
according to the invention, the abovementioned aligning plate is
fixed to the abovementioned reference element, and the
abovementioned hole is drilled in the jaw, and the implant is fixed
in said hole, and subsequently, preferably after the abovementioned
reference element has been removed, the abovementioned
superstructure is fitted on said implant.
[0015] The invention also relates to an aligning plate for use of
the method, having at least one aperture for drilling a hole in the
bone of a lower or an upper jaw of a person, in order to place at
least one implant. Said aligning plate is characterized in that it
has means for fixing it to at least one reference element that is
provided in the abovementioned bone.
[0016] Said means preferably have an opening that connects up in a
virtually exact fit with the abovementioned reference element, so
that the aligning plate can be fixed detachably on the reference
element by means of at least one screw or bolt.
[0017] Other details and advantages of the invention will emerge
from the description that follows of a number of embodiments of the
method and the aligning plate according to the invention; this
description is given merely as an example and does not limit the
scope of the protection claimed; the reference numerals used below
relate to the appended figures.
[0018] FIG. 1 is a diagrammatic top view of a part of a lower jaw
with reference elements according to the invention.
[0019] FIG. 2 is a diagrammatic top view of a part of a lower jaw
with an aligning plate according to the invention.
[0020] FIG. 3 is a diagrammatic front view of the lower jaw and the
aligning plate of FIG. 2.
[0021] FIG. 4 is a diagrammatic front view of a part of a lower jaw
with a superstructure provided with teeth according to the
invention.
[0022] FIG. 5 is a diagrammatic cross section of a reference
element together with an aligning plate, according to the
invention.
[0023] In the various figures the same reference numerals relate to
the same or similar elements.
[0024] The invention relates in general to a method for producing a
dental prosthesis which has to be fixed upon so-called implants
provided in the jawbone of a patient. Such a dental prosthesis
comprises a so-called superstructure, on which artificial teeth are
provided, in a manner that is known per se, and which has fixing
means for fixing to the abovementioned implants. Apart from that,
the invention also relates to a method for producing an aligning
plate that makes it possible in a simple manner to drill very
accurate holes, in which said implants are placed.
[0025] In the case of the method according to the invention,
reference elements are fixed in the jaw on which the superstructure
is to be placed. FIG. 1 shows diagrammatically a toothless lower
jaw 1 in the case of which three reference elements have been fixed
in the bone of said jaw. Each of these reference elements is formed
by a screw 2.
[0026] Said screws 2 are fixed in different positions in the bone
of the jaw 1, in such a way that they project slightly above the
gum surrounding the bone. Furthermore, the screws 2 are relatively
short, but they are still sufficiently long, for example almost 5
mm, to be anchored stably in the jaw.
[0027] A dental impression of said jaw 1, together with the screws
2, is then made in the known manner. On the basis of this
impression, a so-called bite plate is produced, which allows the
position of the upper jaw of the patient to be determined relative
to that of the lower jaw.
[0028] Owing to the fact that when the abovementioned impression is
being taken, the abovementioned screws 2 extend above the gums,
during the production of the bite plate corresponding hollows are
formed in the underside of the bite plate, which hollows permit
said bite plate to be positioned in an exact position in the oral
cavity, the abovementioned hollows connecting up in a virtually
exact fit with the screws 2.
[0029] By means of this bite plate and a so-called articulator, a
wax model is then prepared, this forming a provisional model for
the abovementioned superstructure. This wax model comprises a
relatively rigid bearing structure on which artificial teeth are
fixed with wax. This provisional model likewise has hollows that
correspond to the position of the abovementioned screws 2, in such
a way that it can be positioned virtually perfectly in the oral
cavity of the patient.
[0030] In a variant of the method according to the invention, the
abovementioned hollows are not provided in this provisional model,
but said hollows are formed during the fitting of the model,
through depressions being formed in its bearing structure by the
abovementioned screws 2.
[0031] After the provisional model has been placed on the
corresponding jaw 1 of the patient in this way, a three-dimensional
image is made of said jaw 1, together with this model and the
abovementioned screws 2.
[0032] In order to obtain such a three-dimensional image, it is
preferable to perform a so-called CT scan. The information from
this three-dimensional image is preferably processed
electronically, in order to make it possible to display it in a
simple manner on, for example, a computer screen and to enable it
to be used for certain so-called rapid prototyping techniques.
[0033] From this three-dimensional image, anatomical structures
such as the shape of the bone and the position of the nerve bundles
and the blood vessels in the jaw 1 are deduced. It is then
determined at what positions in the lower jaw and according to what
orientations implants can be placed in the jaw 1 without touching
nerve bundles, blood vessels or other critical anatomical
structures.
[0034] On the basis of this information, an aligning plate 3 is
produced, having apertures 4 with a suitable orientation and
diameter to allow said holes to be drilled through them in the bone
of the jaw 1, in order to fit the abovementioned implants. For this
purpose, the aligning plate 3 is placed on the jaw 1 in the manner
shown in FIGS. 2 and 3. In addition to these apertures 4, means are
also provided for fixing the aligning plate 3 on the abovementioned
screws 2. Said means more specifically comprise openings, the
position of which corresponds to that of the screws 2, and which
can connect up in a virtually exact fit with the latter.
[0035] In this way, the position of the abovementioned apertures 4
is determined relative to said screws 2, and the aligning plate 3
assumes a fixed position relative to the jaw 1 and the screws 2.
This makes it possible in a simple manner to make a hole 5 by means
of a drill, in a manner known per se, for each implant that is to
be placed.
[0036] For making the abovementioned holes 5 it is preferable to
use several bushes with an axial cylindrical opening, in the case
of which their external dimensions virtually correspond to those of
the apertures 4, in such a way that said bushes can be placed in
the latter in a virtually exact fit with them. The axial
cylindrical opening of the various bushes is, however, different.
When the holes 5 are being drilled in the jaw 1, more specifically,
different drills with increasing diameters are used in succession.
This means that at the start of drilling of a hole 5 a drill with a
small diameter is used, in which case a first bush, with a
cylindrical opening whose diameter corresponds to that of the
drill, is placed in the abovementioned aperture 4 of the aligning
plate 3, in order to guide the drill, so that a very accurate hole
can be drilled. A number of successive holes are drilled in this
way, in each case a drill with a larger diameter being used, and in
each case a bush with corresponding dimensions being placed in the
aperture 4, until the hole obtained in this way is large enough for
the placing of an implant.
[0037] As stated above, the position and the orientation of the
abovementioned apertures 4 are selected in such a way that the
blood vessels or the nerve bundles 6 or other critical anatomical
structures cannot be touched during drilling in the jaw 1.
[0038] According to an advantageous embodiment of the method
according to the invention, the aligning plate is made by means of
the abovementioned rapid prototyping techniques. Such techniques
are, for example, stereolithography, selective laser sintering,
fused deposition modelling, laminated object prototyping,
three-dimensional printing, and so forth. In a very interesting
rapid prototyping technique the abovementioned aligning plate 3 is
produced on the basis of the information from the abovementioned
three-dimensional image by milling from, for example, a block of
metal or plastic.
[0039] In addition to the abovementioned aligning plate 3, the
superstructure is also made using one of these rapid prototyping
techniques, starting, on the one hand, from the abovementioned
provisional model and the abovementioned hollows that correspond to
the position of the abovementioned screws 2, and, on the other
hand, from the relative position of the abovementioned apertures 4
in the aligning plate 3, or therefore the desired position of the
implants relative to the screws 2.
[0040] Through the use of the abovementioned screws 2 as reference
elements, it is consequently no longer necessary to make an
impression of the jaw 1 of a patient after the placing of the
implants, and the superstructure can be produced immediately on the
basis of the information from the abovementioned three-dimensional
image.
[0041] The superstructure is preferably produced by means of a
similar rapid prototyping technique to that used for making up the
aligning plate 3.
[0042] In order to fix the abovementioned artificial teeth in a
correct position on the superstructure 7, the abovementioned
provisional model is placed on a holder, with the abovementioned
hollows connecting up in a virtually exact fit with supporting
points provided on said holder. The mutual position of said
supporting points therefore corresponds to the mutual position of
the abovementioned reference elements. The provisional model with
the artificial teeth is then cast in a plastic, in order to form a
so-called plastic key, said plastic key forming a contact face with
the holder. The wax and the bearing structure are then removed from
the plastic key according to techniques that are known per se, the
artificial teeth remaining behind in a fixed position in the
plastic. If a setting silicone is used for the abovementioned
plastic, said plastic key is called a silicone key.
[0043] Finally, in order to fix the artificial teeth on the
superstructure, the latter is placed on the holder, in which case
the hollows corresponding to the reference elements connect up in a
virtually exact fit with the abovementioned supporting points. In
this way the superstructure assumes the same position relative to
the holder as the provisional model during the making up of the
plastic key. The plastic key is then placed over the
superstructure, care being taken to ensure that the plastic key is
positioned in an identical manner relative to the holder. This is
carried out more specifically by placing the plastic key with the
same contact surface and in the same way against the holder as was
the case during its manufacture. Finally, a synthetic resin is
placed in the plastic key, in a manner known per se, between the
superstructure 7 and the artificial teeth. When this synthetic
resin has set, in such a way that the teeth are immovably connected
to the superstructure, the plastic key is removed from the
superstructure and the artificial teeth.
[0044] FIG. 4 shows diagrammatically a superstructure 7 produced in
this way, with artificial teeth 8 placed on it. Said superstructure
7 is fitted on implants 9 and 10, which are provided in the holes 5
drilled in the lower jaw 1.
[0045] FIG. 5 shows diagrammatically a reference element that is
formed by a screw 2. Said screw 2 is fixed through the gum 11 in
the bone of a jaw 1 and has a preferably polygonal head 12, which
extends above the gum 11. The head 12 has on its top side a
cylindrical threaded opening 13 which is coaxial with the screw 2.
Fixed in this opening 13 is a bolt 14, which allows the
abovementioned aligning plate 3 to be fixed to the screw 2.
[0046] For this purpose, the aligning plate 3 has at a position
corresponding to that of the screw 2 an opening that connects up in
a virtually exact fit with the head 12 of the screw 2, said opening
having a collar 15 that rests on the top of the head 12. The
abovementioned bolt 14 extends through the opening in the aligning
plate 3.
[0047] In a variant of the above embodiment of the method and the
aligning plate according to the invention, the abovementioned
aligning plate 3 is formed by the superstructure 7, so that it is
not necessary to manufacture a separate aligning plate 3. In such a
case the abovementioned apertures 4 are made in the superstructure
7, and after the implants 9 and 10 have been placed the
superstructure is fixed on said implants by means of screws or
bolts suitable for the purpose.
[0048] The reference elements 2 are preferably removed from the jaw
1 before the final placing of the superstructure 7.
[0049] When reference is made in this description to the bone of a
lower or an upper jaw (1), this also includes the bone parts
connected to said jaw (1).
[0050] Notwithstanding the fact that in the above description and
in the appended figures a superstructure that is fixed to a lower
jaw with the aid of two implants has been described, the invention
also relates to a method and an aligning plate in the case of which
three or more implants are provided in the lower jaw, or in the
case of which only one implant is used. In addition, the dental
prosthesis produced in this way need not extend over the entire jaw
1, but it may have only a few teeth and be fitted on one implant.
The invention is also equally usable for producing and fitting a
superstructure for an upper jaw.
[0051] The invention is in no way limited to the embodiments of the
method, the superstructure and the aligning plate according to the
invention described above and proposed in the figures, but a number
of variants can be considered within the scope of this invention,
both as regards the reference elements and as regards the
dimensions and shapes of the aligning plate.
* * * * *