U.S. patent application number 13/910451 was filed with the patent office on 2013-12-12 for methods for producing a laboratory analogue for dental implants.
The applicant listed for this patent is Heraeus Kulzer GMBH. Invention is credited to Uwe BOEHM, Stefan HORMANN, Helmut REDEMANN, Yohannes WOLDEGERGIS.
Application Number | 20130330689 13/910451 |
Document ID | / |
Family ID | 48613426 |
Filed Date | 2013-12-12 |
United States Patent
Application |
20130330689 |
Kind Code |
A1 |
WOLDEGERGIS; Yohannes ; et
al. |
December 12, 2013 |
METHODS FOR PRODUCING A LABORATORY ANALOGUE FOR DENTAL IMPLANTS
Abstract
A method for producing a three-dimensional model of a region of
a jaw for producing a dental restoration includes fully-automatic
shaping of a recess for accommodating a laboratory analogue into
the alveolar ridge of the model. Three-dimensional scanning data is
used in the shaping and the depth, position, and orientation of the
recess are shaped such that the crestal end of the laboratory
analogue inserted into the recess coincides with the crestal end of
the dental implant in the jaw of a patient. The method may also
include fully-automatic shaping of a vestibular, lingual or
palatinal feed-through through the model into the recess, wherein
the three-dimensional scanning data are used in the shaping and the
feed-through is arranged such that the crestal end of a laboratory
analogue coincides with the crestal end of the dental implant in
the jaw of the patient, when the laboratory analogue is fixed in
place.
Inventors: |
WOLDEGERGIS; Yohannes;
(Hanau, DE) ; HORMANN; Stefan; (Waechtersbach,
DE) ; REDEMANN; Helmut; (Frankfurt am Main, DE)
; BOEHM; Uwe; (Hanau, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Heraeus Kulzer GMBH |
Hanau |
|
DE |
|
|
Family ID: |
48613426 |
Appl. No.: |
13/910451 |
Filed: |
June 5, 2013 |
Current U.S.
Class: |
433/213 ;
29/896.1 |
Current CPC
Class: |
A61C 13/0004 20130101;
B29L 2031/7536 20130101; A61C 13/0006 20130101; A61C 9/0053
20130101; A61C 13/34 20130101; Y10T 29/49567 20150115; B33Y 80/00
20141201; A61C 8/0001 20130101; B33Y 10/00 20141201 |
Class at
Publication: |
433/213 ;
29/896.1 |
International
Class: |
A61C 8/00 20060101
A61C008/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 6, 2012 |
DE |
DE102012011238.6 |
Claims
1. A method for producing a laboratory analogue (1, 21, 31) for
dental implants comprising the steps of: providing at least one
sleeve (11) comprising a cylindrical depression (4) having an
internal thread; providing a three-dimensional model (6, 16, 26,
36) of at least a partial region of a jaw of a patient who harbors
at least one dental implant; inserting at least one sleeve (11)
into at least one recess (7) of the model (6, 16, 26, 36) matching
the sleeve (11), each recess (7) being arranged in a region of the
model (6, 16, 26, 36), in which a dental implant is arranged in the
jaw of the patient; and fully-automatic ablation of the at least
one inserted sleeve (11), wherein the ablation is controlled
through three-dimensional scanning data of an oral space of the
patient, wherein the data was recorded previously, and wherein the
sleeve (11) is ablated based on such data to the extent that a
crestal end of a laboratory analogue (1, 21, 31) produced from the
sleeve (11) coincides with a crestal end of the dental implant in
the jaw of the patient.
2. The method according to claim 1, wherein the sleeve (11) is
ablated proceeding from a crestal direction.
3. A method for producing a three dimensional model (6, 16, 26, 36)
of at least a partial region of a jaw for producing a dental
restoration, the method comprising the steps of: providing
three-dimensional scanning data of an oral space of a patient who
harbors at least one dental implant, wherein the data was recorded
previously; preparing a three-dimensional model (6, 16, 26, 36) of
at least the partial region of the jaw; and fully-automatic shaping
of at least one recess (7) for accommodating a laboratory analogue
(1, 21, 31) into an alveolar ridge of the model (6, 16, 26, 36),
wherein the three-dimensional scanning data is used in the shaping
and a depth, a position, and an orientation of the at least one
recess (7) are shaped such that a crestal end of the laboratory
analogue (1, 21, 31) inserted into the recess (7) coincides with a
crestal end of a dental implant in the jaw of the patient.
4. The method according to claim 3, wherein the laboratory analogue
(1, 21, 31) is configured to be inserted into the recess (7) or a
sleeve (11) is configured to be inserted into the recess (7),
wherein the laboratory analogue (1, 21, 31) is produced from the
sleeve (11) through ablation, and wherein the three-dimensional
scanning data is used to ablate the sleeve (11)
fully-automatically.
5. A method for producing a three dimensional model (6, 16, 26, 36)
of at least a partial region of a jaw for producing a dental
restoration, the method comprising the steps of: providing
three-dimensional scanning data of an oral space of a patient who
harbors at least one dental implant, wherein the data was recorded
previously; preparing a three-dimensional model (6, 16, 26, 36) of
at least a partial region of the jaw with at least one recess (7)
for accommodating a laboratory analogue (21) having an opening
(25), wherein each recess (7) is arranged in a region of the model
(6, 16, 26, 36) in which a dental implant is arranged in the jaw of
the patient; and fully-automatic shaping of at least one
vestibular, lingual or palatinal feed-through (28) through the
model (6, 16, 26, 36) into the at least one recess (7), wherein the
three-dimensional scanning data is used in the shaping and the
feed-through (28) is arranged such that a crestal end of one
laboratory analogue (1, 21, 31) coincides with a crestal end of the
dental implant in the jaw of the patient when the laboratory
analogue (21) is fixed in place with a pin that is inserted through
the feed-through (28) in the model (6, 16, 26, 36) into an opening
(25) in the laboratory analogue (1, 21, 31).
6. The method according to claim 5, wherein the feed-through (28)
is shaped to match the pin and the opening (25) matches the pin,
preferably in that a depression in the laboratory analogue (21)
arranged downstream of the opening matches the pin.
7. The method according to claim 3, wherein the fully-automatic
shaping proceeds by drilling, turning, grinding, cutting out and/or
milling.
8. The method according to claim 1, wherein the fully-automatic
ablation is carried out in computer-supported manner at an accuracy
of at least .+-.10 .mu.m.
9. The method according to claim 1, wherein the three-dimensional
scanning data of the oral space of the patient is used in the
production of the three-dimensional model (6, 16, 26, 36) of the
region of the jaw, and wherein the model (6, 16, 26, 36) is
produced by rapid prototyping at an accuracy of at least .+-.100
.mu.m.
10. The method according to claim 1, wherein a CAD-based
stereolithographic method is used to obtain the data for production
of the model (6, 16, 26, 36) and/or the laboratory analogue (1, 21,
31), and wherein the model (6, 16, 26, 36) is fabricated from a
plastic material.
11. The method according to claim 1, wherein a five-axis processing
is used in the ablation.
12. The method according to claim 1, wherein at least two recesses
(7) are generated or exist in the three-dimensional model (6, 16,
26, 36) and one sleeve (11) each or one laboratory analogue (1, 21,
31) each is configured to be inserted into each of the recesses
(7), and wherein the position of the recess (7) or feed-throughs
(28) and/or crestal ends of the laboratory analogues (1, 21, 31)
with respect to each other are adjusted by means of shaping and/or
ablating based on the scanning data.
13. The method according to claim 1, wherein at least one
cylindrical or conical recess (7) is generated or exists in the
model (6, 16, 26, 36), wherein the recess (7) is generated or
exists to have a one-fold or n-fold rotational symmetry about a
longitudinal axis of the recess (7), and wherein a sleeve (11) or a
laboratory analogue (1, 21, 31) with the same rotational symmetry
at least over regions thereof is configured to be inserted into the
recess such that it fits in the recess (7) only in one orientation
or in the n-fold orientation.
14. The method according to claim 1, wherein the at least one
recess (7) is predefined during the production of the model (6, 16,
26, 36) to have a fixed defined shape that matches a certain shape
of the sleeve (11) or the laboratory analogue (1, 21, 31), and/or a
shape of the recess (7) is selected from a multiplicity of
different shapes that match a multiplicity of different sleeves
(11) or laboratory analogues (1, 21, 31), wherein the shape is
integrated into a measured virtual digitized jaw model (6, 16, 26,
36) as the recess (7) before the model (6, 16, 26, 36) is
produced.
15. A laboratory analogue produced according to the method of claim
1, wherein the crestal end of the laboratory analogue (1, 21, 31)
corresponds to the data of the three-dimensional scan of the oral
space of the patient at an accuracy of at least .+-.10 .mu.m when
it is inserted in a corresponding model (6, 16, 26, 36) of the
jaw.
16. A model of at least a partial region of a jaw produced
according to the method of claim 3, the model comprising the at
least one recess (7), wherein the accuracy of the dimensions of the
at least one recess (7) and the orientation and position of all
recesses (7) with respect to each other is at least .+-.10 .mu.m
relative to the three-dimensional scanning data of the oral space
of the patient, such that the orientation and position of the
crestal ends of the laboratory analogues (1, 21, 31) inserted in
the model (6, 16, 26, 36) correspond to the orientation and
position of all crestal ends of the dental implants at said
accuracy.
17. A model of at least a partial region of a jaw produced
according to the method of claim 5, the model comprising the at
least one feed-through and the at least one recess (7), wherein the
accuracy of the position of the at least one feed-through (28) and
the orientation and position of all feed-throughs (28) with respect
to each other is at least .+-.10 .mu.m relative to the
three-dimensional scanning data of the oral space of the patient,
such that the orientation and position of the crestal ends of the
laboratory analogues (1, 21, 31) fixed in the model (6, 16, 26, 36)
with the pins extending through the feed-throughs (28) corresponds
to the orientation and position of all crestal ends of the dental
implants at said accuracy.
18. A laboratory analogue produced according to the method of claim
7, wherein the crestal end of the laboratory analogue (1, 21, 31)
corresponds to the data of the three-dimensional scan of the oral
space of the patient at an accuracy of at least .+-.10 .mu.m when
it is inserted in a corresponding model (6, 16, 26, 36) of the jaw.
Description
BACKGROUND OF THE INVENTION
[0001] The invention relates to methods for producing a laboratory
analogue using three-dimensional scanning data of the oral space of
the patient, whereby the data was recorded previously.
[0002] The invention also relates to methods for producing a
three-dimensional model of at least a partial region of a jaw of a
patient for at least one laboratory analogue having at least one
recess for accommodating at least one laboratory analogue using
three-dimensional scanning data of the oral space of the patient,
whereby the data was recorded previously.
[0003] And lastly, the invention also relates to a laboratory
analogue and a model produced using the method.
[0004] Dental implants are used in dental medicine to replace teeth
that have fallen out or were extracted. Dental implants are
inserted into the jaw bone for this purpose. Dental implants to be
inserted into the jaw bone are known from DE 10 2007 029 105 A1.
The dental implant comprises a cylindrical bore hole having an
internal thread. Moreover, the dental implant is structured to have
marks that are designed to ensure that the superstructure cannot be
inserted into the dental implant at arbitrary angles.
[0005] Laboratory analogues are needed to allow a dental technician
to carve a restoration on an implant superstructure in the
laboratory for later insertion in the patient. For this purpose,
laboratory analogues have a material-specific geometry and shape.
In most cases, an impression is taken with an impression compound
for this purpose and subsequently used to fabricate a plaster model
of the jaw of the patient by casting plaster into the impression.
The laboratory analogue becomes integrated into the model of the
jaw in the appropriate position during this process. The geometry
and shape of the laboratory analogue need to be matched to the
plaster for this purpose. The model of the jaw with the integrated
laboratory analogue is then used by the dental technician to shape
the implant superstructure and the dental restoration to match the
situation existing in the oral space of the patient.
[0006] Another method for providing a model of the jaw and the
incorporation scenario has been in use for some time instead of the
above-described method. It involves the use of, e.g., an intraoral
scanner to first record the three-dimensional situation in the oral
space of the patient and storing this digital information in
electronic memory of a computer. Most often, CAD programs are used
for this purpose. Subsequently, a model of the jaw is generated in
known manner using a light-curing plastic material and a laser. The
laboratory analogues are then inserted into the plastic models of
the jaw. In turn, the plastic model of the jaw harboring the
laboratory analogue can then be used by the dental technician to
build up the dental restoration.
[0007] A disadvantage of this procedure is that the incorporation
situation is not exactly defined for the dental technician on the
jaw model. In particular, where superstructures need to be fixed to
multiple dental implants in the jaw of the patient, undesired
tension may be produced in the jaw bone if the position and the
orientation of the laboratory analogues in the model do not match
the situation in the oral space to a sufficiently accurate degree.
This can cause the patient pain and can put stress on the jaw bone
which may lead to implant loss in the worst case. For this reason,
it is crucial as early as during the production of the model and
the positioning and orientation of the laboratory analogues with
respect to each other to carry out all steps at the highest
accuracy possible.
[0008] If the dental restoration inserted by the dentist does not
exactly match the situation in the oral space of the patient, the
dentist may need to adapt the dental restoration on site or, in the
worst case, have the entire dental restoration re-fabricated.
Moreover, the laboratory analogue is not all that easy to affix in
the proper position such that there may some changes of position
during the production of the dental restoration resulting in
incorrect fitting of the dental restoration. This is the case,
because the laboratory analogue is arranged on the model such that
it can rotate and shift in its longitudinal direction.
BRIEF SUMMARY OF THE INVENTION
[0009] Accordingly, it is the object of the invention to overcome
the disadvantages of the prior art. Specifically, a way is to be
devised that allows a model of the jaw or a laboratory analogue, in
particular a plastic model of the jaw fabricated through rapid
prototyping, with laboratory analogues inserted for producing a
dental restoration to be produced at the highest possible accuracy
such that there is less scrap during the production of the dental
restoration and such that the dentist inserting the dental
restoration has to carry out fewer or no additional adaptations.
Moreover, modern methods should be usable in the production of the
model of the jaw.
[0010] The method-related object of the invention is met through a
method for producing a laboratory analogue for dental implants
comprising the steps of:
[0011] providing at least one sleeve comprising a cylindrical
depression having an internal thread;
[0012] providing a three-dimensional model of at least a partial
region of the jaw of a patient who harbors at least one dental
implant;
[0013] inserting at least one sleeve into at least one recess of
the model matching the sleeve, whereby each recess is arranged in a
region of the model, in which a dental implant is arranged in the
jaw of the patient; and
[0014] fully-automatic ablation of at least one inserted sleeve,
whereby the ablation is controlled through three-dimensional
scanning data of the oral space of the patient, whereby the data
was recorded previously, and the sleeve is ablated based on such
data to the extent that the crestal end of the laboratory analogue
produced from the sleeve coincides with the crestal end of the
dental implant in the jaw of the patient.
[0015] In this context, the invention can provide the sleeve to be
ablated, in particular cut, ground and/or milled off, proceeding
from the crestal direction.
[0016] The method-related object of the invention is also met by a
method for producing a three-dimensional model of at least a
partial region of a jaw for producing a dental restoration,
comprising the steps of:
[0017] providing three-dimensional scanning data of an oral space
of a patient, who harbors at least one dental implant, whereby the
data was recorded previously;
[0018] preparing a three-dimensional model of at least the partial
region of the jaw; and
[0019] fully-automatic shaping of at least one recess for
accommodating a laboratory analogue into the alveolar ridge of the
model, whereby the three-dimensional scanning data is used in the
shaping and the depth, position, and orientation of the at least
one recess are shaped such that the crestal end of the laboratory
analogue inserted into the recess coincides with the crestal end of
the dental implant in the jaw of the patient.
[0020] In this context, the invention can provide the laboratory
analogue, in particular a standard laboratory analogue, to be
inserted into the recess or a sleeve to be inserted into the
recess, whereby a laboratory analogue is produced from the sleeve
through ablation, whereby it is preferable to use the
three-dimensional scanning data in order to ablate the sleeve
fully-automatically.
[0021] This method allows the advantages of a method according to
the invention for producing the laboratory analogue and having the
recess in the model to be combined.
[0022] Moreover, the method-related object of the invention is met
by a method for producing a three-dimensional model of at least a
partial region of a jaw for producing a dental restoration,
comprising the steps of:
[0023] providing three-dimensional scanning data of an oral space
of a patient, who harbors at least one dental implant, whereby the
data was recorded previously;
[0024] preparing a three-dimensional model of at least a partial
region of the jaw with at least one recess for accommodating a
laboratory analogue having an opening, whereby each recess is
arranged in a region of the model, in which a dental implant is
arranged in the jaw of the patient; and
[0025] fully-automatic shaping of at least one vestibular, lingual
or palatinal feed-through through the model into the at least one
recess, whereby the three-dimensional scanning data are used in the
shaping and the feed-through is arranged such that the crestal end
of a laboratory analogue coincides with the crestal end of the
dental implant in the jaw of the patient when the laboratory
analogue is fixed in place with a pin that is inserted through the
feed-through in the model into an opening in the laboratory
analogue.
[0026] In this context, the invention can provide the feed-through
to be shaped to match the pin and the opening to match the pin,
preferably in that a depression in the laboratory analogue arranged
downstream of the opening matches the pin.
[0027] Moreover, methods according to the invention for producing
models can provide the fully-automatic shaping to proceed by means
of drilling, turning, grinding, cutting out and/or milling.
[0028] The production methods can be implemented in particularly
precise and efficient manner through the use of fully-automatic
computer-supported methods.
[0029] The invention can also provide the fully-automatic shaping
and/or ablation, which is preferably carried out in
computer-supported manner, to be carried out at an accuracy of at
least .+-.10 .mu.m, preferably at an accuracy of at least .+-.5
.mu.m.
[0030] Such accuracy is sufficient to allow the abutments, abutment
superstructures, and other superstructures to be attached to the
dental implants without any tension arising. Moreover, at the
specified accuracies, the scan of the oral space can be carried out
with known methods without any major effort.
[0031] Moreover, the invention can provide the three-dimensional
scanning data of the oral space of the patient to be used in the
production, in particular fully-automatic production, of the
three-dimensional model of the jaw or region of the jaw, whereby
the model is preferably produced by means of rapid prototyping
(rapid model construction), particularly preferably at an accuracy
of at least .+-.100 .mu.m, yet more preferably at an accuracy of at
least .+-.60 .mu.m.
[0032] Combining the easy and inexpensive production of the model
with the refinement attained through fully-automatic ablation of
the sleeve or shaping of the recess or feed-through results in a
method that is rapid and as inexpensive as possibly and
concurrently offers high accuracy and a precise starting position
for the dental technician.
[0033] Another refinement of the invention can provide for the use
of a CAD-based stereolithographic method to obtain the data for
production of the model and/or laboratory analogue, and for the
model to preferably be fabricated from plastic material,
particularly preferably from a light-curing plastic material.
[0034] In this context, the previously recorded scanning data of
the oral space of the patient can be used again and it is feasible
to almost fully automate the production of the model with the
laboratory analogue or laboratory analogues.
[0035] Particularly preferably, the invention provides for the use
of a five-axis processing, in particular a five-axis CNC milling
machine, in the shaping and/or ablation, in particular for milling
and/or grinding.
[0036] The five-axis processing enables better accuracy during the
processing than rapid prototyping and thus leads to improved
models.
[0037] Moreover, the invention can provide at least two recesses to
be generated or to exist in the three-dimensional model and
preferably one sleeve each or one laboratory analogue each to be
inserted into each of the recesses, whereby the position of the
recess or feed-throughs and/or crestal ends of the laboratory
analogues with respect to each other are adjusted by means of
shaping and/or ablating based on the scanning data.
[0038] The advantages of the invention are implemented in
particular if multiple laboratory analogues are used to build up a
superstructure to be attached to multiple dental implants, since
the method allows especially the position and orientation of the
laboratory analogues with respect to each other to be adjusted very
accurately.
[0039] Moreover, the invention can provide at least one cylindrical
or conical recess to be generated or to exist in the model, whereby
the recess is generated or exists to have one-fold or n-fold
rotational symmetry about the longitudinal axis of the recess, and
a sleeve or a laboratory analogue with the same rotational
symmetry, at least over regions thereof, to be inserted into the
recess such that it fits in the recess only in one orientation or
in the n-fold orientation.
[0040] This serves to always attach the superstructures and/or
abutments in the correct position in the model and, later, on the
dental implants in the oral space.
[0041] In this context, the invention can provide that at least one
sleeve or one laboratory analogue is used which preferably fits in
the recess in a perfect fit.
[0042] Methods according to the invention can also be characterized
in that the at least one recess is predefined during the production
of the model to have a fixed defined shape that fits a certain
shape of a sleeve or laboratory analogue, and/or a shape of the
recess to be selected from a multiplicity of different shapes that
match a multiplicity of different sleeves or laboratory analogues,
whereby the shape is integrated into a measured virtual digitized
jaw model as a recess preferably before the model is produced.
[0043] The invention can just as well provide at least one sleeve
or at least one laboratory analogue to snap-in into counter-snap-in
locking means by means of snap-in locking means or is connected
through a bayonet closure in an angled depression of at least one
recess.
[0044] The longitudinal axis of the recess is the axis along which
the laboratory analogue can be introduced into or removed from the
recess. It usually coincides with the central axis of the recess. A
crestal direction shall be understood to mean a direction from the
alveolar ridge of premolar teeth in occlusal direction, i.e. toward
the mastication surface. Direction information such as vestibular
(towards the oral vestibule), lingual (on the tongue side of the
mouth in case of the lower jaw), and palatinal (on the cheek side
in the mouth in case of the upper jaw) also refers to the jaw.
[0045] Referring to one-fold rotational symmetry axes, reference is
made to the one-fold rotational symmetry axis that coincides with
the rotational symmetry axis of the cylindrical or conical basic
shape of the sleeve and/or laboratory analogue. In most cases, a
cylindrical or conical shape is selected as the basic shape of the
laboratory analogue and thus of the recess, whereby grooves,
depressions or projections break the symmetry of the basic shape.
Accordingly, the rotational symmetry axis of the basic shape is to
be seen as the symmetry axis.
[0046] Moreover, the invention can provide for a CAD-based
stereolithographic method to be used for producing the model and
the model to preferably be fabricated from plastic material,
particularly preferably from a light-curing plastic material.
[0047] The methods are particularly well-suited for implementing
methods according to the invention since the recesses can thus be
integrated very easily and without major computation into the jaw
models even with simple, easily obtainable computers.
[0048] The invention can just as well provide for the dental
restoration to be screwed directly to the laboratory analogue as
the final step of the method. Alternatively, an abutment
superstructure and/or implant superstructure can be mounted on the
laboratory analogue and finalized.
[0049] Preferably, methods according to the invention can just as
well provide for a computer to be used during the production of the
recess or feed-through, in particular a digitization of the oral
space of the patient, whereby the shape of the recess is read-out
from a memory unit of the computer and whereby different fitting
shapes of recesses are assigned, in particular, to different
laboratory analogues, whereby these are preferably selected by the
computer and/or a user using an input unit.
[0050] Using a computer for production of the model results in a
special combination effect in that all data for production of the
model are already stored on the computer, which means that the
surface of the model is stored therein. In this case, the surface
of the model only needs to be modified appropriately such that the
recess becomes arranged at the proper site thereof to match the
laboratory analogue that is best suited or which has previously
been selected by the computer or is the only one stored therein.
The model can then be produced to have the modified surface right
away, meaning jointly with the matching recess.
[0051] The invention can just as well provide for the use of a
laboratory analogue that has the same rotational symmetry along its
longitudinal axis, at least over regions thereof, as the recess and
which preferably fits in the recess in a perfect fit or whose
thread perfectly fits the counter-thread of the recess.
[0052] Using a laboratory analogue of this type ensures that the
recess matches the region of the laboratory analogue and therefore
ensures that the laboratory analogue is attached well in the
model.
[0053] The invention can provide the recess to be predefined during
the production of the model to have a fixed defined shape that
matches a certain laboratory analogue, and/or a shape of the recess
to be selected from a multiplicity of different shapes that match a
multiplicity of different laboratory analogues, whereby the shape
is being integrated as a recess into a measured virtual digitized
model of the jaw, preferably before the model is produced.
[0054] This allows a particularly user-friendly and/or variable
method to be designed. The strength of the invention can be
implemented in beneficial manner especially through these
options.
[0055] The use of computers for implementing methods according to
the invention is particularly suitable, since especially the more
recent methods are already in use in computer-supported manner for
producing the models, such that there is only a need to include a
simple software supplement and the data related to the surfaces of
the recesses and/or laboratory analogues in order to improve the
dental restoration thus produced.
[0056] In this context, the invention can provide multiple shapes
of different recesses to be stored in the storage unit and one
recess to be selectable through an input facility and/or to be
defined by the computer based on model preparation data, whereby
the recess, in particular, can be selected from a
computer-determined pre-selection of recesses that match the
laboratory analogues.
[0057] The object of the invention is also met by a laboratory
analogue produced according to a method according to the invention
for producing a laboratory analogue, in which the crestal end of
the laboratory analogue corresponds to the data of the
three-dimensional scan of the oral space of the patient at an
accuracy of at least .+-.10 .mu.m, preferably at an accuracy of at
least .+-.5 .mu.m, when it is inserted in a corresponding model of
the jaw.
[0058] The object of the invention is also met by a model of at
least a partial region of a jaw, produced according to a method of
this type for producing a model, comprising at least one recess, in
which the accuracy of the dimensions of the at least one recess and
preferably the orientation and position of all recesses with
respect to each other is at least .+-.10 .mu.m, preferably the
accuracy is at least .+-.5 .mu.m, relative to the three-dimensional
scanning data of the oral space of the patient such that the
orientation and position of the crestal ends of the laboratory
analogues inserted in the model corresponds to the orientation and
position of all crestal ends of the dental implants at the
accuracy.
[0059] And finally, the object of the invention is also met by a
model of at least a partial region of a jaw, produced according to
a method of this type for producing a model, comprising at least
one feed-through and at least one recess, in which the accuracy of
the position of the at least one feed-through and preferably the
orientation and the position of all feed-throughs with respect to
each other is at least .+-.10 .mu.m, preferably the accuracy is at
least .+-.5 .mu.m, relative to the three-dimensional scanning data
of the oral space of the patient such that the orientation and
position of the crestal ends of the laboratory analogues affixed in
the model by means of the pins extending through the feed-throughs
corresponds to the orientation and position of all crestal ends of
the dental implants at the accuracy.
[0060] A model of this type provides a basis for the use of a
rotationally-fixed and even position-fixed superstructure for
producing high quality dental restorations.
[0061] In this context, the invention can provide counter-snap-in
means in the recess that engage snap-in means on the laboratory
analogue and keep the laboratory analogue in a fixed position.
[0062] This again serves to affix a laboratory analogue inserted
into the recess of the model both better and more accurately.
[0063] The possibility of using different laboratory analogues and
the selection of a particularly well-suited laboratory analogues
allow for further improvements to be made to the final result thus
produced.
[0064] The invention is based on the surprising finding that the
quality and especially the accuracy of the dental restoration
produced with modern methods such as "rapid prototyping" and/or
stereolithographic methods for producing jaw models can be improved
through reproducing the accuracy of the scan in the model or
laboratory analogue or laboratory analogues by utilizing the scan
data in the automatic shaping or ablating during the production of
the model and/or during the production of the laboratory analogue
or laboratory analogues. This can be effected according to the
invention, preferably through the use of five-axis procedures such
as five-axis polishers, mills, cutters and/or drills that are
controlled based on the scan data of the oral space of the patient.
In this context, various other measures according to the invention
can allow the laboratory analogues to be arranged particularly
positionally-precise, non-rotatably or even in fixed position.
[0065] The methods according to the invention allow not only the
position of an individual crestal end of a single laboratory
analogue to be defined accurately, but also, and mainly, the
position and orientation with respect to each other of different
crestal ends of multiple laboratory analogues to be adjusted
accurately. This results in advantages during the production of
superstructures that are to be attached to multiple dental
implants.
[0066] Moreover, the recess can be produced to have the properly
fitting shape right when it is produced in the jaw model if the
surface required for the recess is integrated into a virtual model
right away and each recess is generated right away accordingly
during the production. Moreover, it is also feasible to right away
select a particularly well-fitting recess with a matching
laboratory analogue if multiple different laboratory analogues and
the matching recesses are stored and thus are available for
selecting.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0067] The foregoing summary, as well as the following detailed
description of the invention, will be better understood when read
in conjunction with the appended drawings. For the purpose of
illustrating the invention, there are shown in the drawings
embodiments which are presently preferred. It should be understood,
however, that the invention is not limited to the precise
arrangements and instrumentalities shown.
[0068] In the drawings:
[0069] FIG. 1 shows a schematic perspective view of a laboratory
analogue having a projection for forming a bayonet closure for
implementing a method according to an embodiment of the
invention;
[0070] FIG. 2 shows a schematic perspective and transparent partial
view of a jaw model for accommodating the laboratory analogue
according to FIG. 1 for implementing a method according to an
embodiment of the invention;
[0071] FIG. 3 shows a schematic perspective view of a sleeve with
broken rotational symmetry for implementing a method according to
an embodiment of the invention;
[0072] FIG. 4 shows a schematic perspective and transparent partial
view of a jaw model for accommodating a sleeve according to FIG. 3
for implementing a method according to an embodiment of the
invention;
[0073] FIG. 5 shows a schematic perspective view of an alternative
laboratory analogue for implementing a method according to an
embodiment of the invention;
[0074] FIG. 6 shows a schematic perspective, transparent partial
view of a jaw model having a feed-through for fixation of a
laboratory analogue according to FIG. 5 for implementing a method
according to an embodiment of the invention;
[0075] FIG. 7 shows a schematic perspective view of another
laboratory analogue for implementing a method according to an
embodiment of the invention; and
[0076] FIG. 8 shows a detail of a schematic cross-sectional view of
a jaw model for implementing a method according to an embodiment of
the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0077] FIG. 1 shows a laboratory analogue 1 that is well-suited for
implementing a method according to the invention. The laboratory
analogue 1 has a cylindrical base 2 that is fabricated from metal.
The laboratory analogue 1 can be fabricated, for example, from
metal. A hexagonal superstructure 3 is arranged on the top of the
laboratory analogue 1.
[0078] If a laboratory analogue 1 or a sleeve with a hexagonal
superstructure 3 is used, the abutment has on its base-side a
6-fold rotational symmetry, i.e. that the region and the surface of
the abutment can be made to geometrically coincide with itself
through six different rotations of less than 360.degree. about its
longitudinal axis. The term, abutment, can also be understood to
mean an implant superstructure with connection geometry. A
rectangular or elliptical superstructure would lead to 2-fold
symmetry and can be used just as well. The abutment can therefore
be placed on the laboratory analogue 1 at defined angles only.
[0079] A cylindrical hole 4 having an internal thread 4 is arranged
in the center of the laboratory analogue 1. The hole 4 extends deep
into the inside of the base 2 and along the symmetry axis of the
cylindrical base 2. But the hole 4 preferably does not extend all
the way to the opposite side of the laboratory analogue 1.
[0080] A projection 5 is attached on the jacket surface of the
cylindrical base 2 and can take the shape of a semi-sphere. The
projection 5 is to form a bayonet closure in concert with a
corresponding recess in a jaw model of a patient.
[0081] A part of a model 6 of this type is shown in a transparent
schematic view in FIG. 2. The model 6 continues on the right and
left as is indicated through the non-finalized straight lines in
FIG. 2. In reality, the model 6 is preferably not to have the type
of edges shown through the straight lines, but shows an alveolar
ridge with or without teeth depending on the actual situation in
the oral space of the patient.
[0082] A recess 7 is situated in the model 6 and extends into the
model 6 as a cylindrical hole. The diameter of the recess 7 is
slightly larger than the diameter of the laboratory analogue 1
according to FIG. 1, such that the laboratory analogue 1 can be
inserted into the recess. An angled groove 8 is provided in the
cylinder wall of the recess 7 and forms a bayonet closure in
concert with the projection 5 according to FIG. 1. The laboratory
analogue 1 can be attached in the model 6 through inserting the
laboratory analogue 1 into the recess 7, whereby the projection 5
is guided in the groove 7. The laboratory analogue 1 preferably
cannot be inserted further at the angling of groove 7, but is
rotated clockwise until it reaches the limit stop of groove 7 and
projection 5 blocks any further rotation.
[0083] The laboratory analogue 1 is fabricated from a sleeve (not
shown) that is slightly longer than the laboratory analogue 1
shown, but already has the same diameter as the base 2 and has a
hexagonal superstructure 3 and the projection 5. The sleeve is
preferably firmly connected to the model 6 by means of the bayonet
closure 5, 8.
[0084] The sleeve is then milled off by means of a five-axis
milling machine, whereby the five-axis milling machine is
controlled automatically based on previously recorded
three-dimensional scanning data of the oral space of the patient.
In this context, the orientation and position of the crestal end of
the sleeve are milled off at high accuracy such that the end
corresponds very closely to the orientation and position of the
crestal end of the dental implant in the jaw of the patient once it
is milled off. Especially the position and orientation of multiple
dental implants with respect to each other is reproduced very
accurately in the model 6 in this process. The laboratory analogues
1 in the model 6 thus produced from the sleeves are then very
well-suited for producing the superstructure, in particular a
superstructure anchored on multiple dental implants.
[0085] In contrast, the model 6 can initially be produced through
simple rapid prototyping since the inaccuracies in the production
of the model are evened out later on through after-working with the
five-axis milling machine.
[0086] FIG. 3 shows a schematic perspective view of a sleeve 11 for
an alternative laboratory analogue that has a base 2 with a flat
portion 15. The purpose of the flat portion 15 is to ensure that
the sleeve 11 and the laboratory analogue fabricated from the
sleeve 11 can be inserted into the matching model 16 according to
FIG. 4 in one position only. The sleeve 11 also has a hexagonal
superstructure 3 for orientation of an abutment and a hole 4 with
an internal thread for attachment of the abutment. Accordingly, the
sleeve 11 resembles the laboratory analogue 1 according to FIG. 1.
Basically, it is conceivable, although unlikely, that the
unprocessed shape of the sleeve 11 would perfectly match the
situation inside the oral space. In this case, the sleeve 11 could
be used directly as a laboratory analogue. This means that there is
no fundamental difference between the sleeve 11 and the finished
laboratory analogue. However, the sleeve 11 should usually be
longer since it generally cannot be made longer artificially and
needs to be milled off or ablated in any other manner to be able to
produce laboratory analogues of any length from the sleeve 11.
[0087] The model 16 has a recess 7 which also comprises a flat
portion 18, such that the shape of the recess 7 matches the shape
of the base 2 of the sleeve 11. Once the sleeve 11 is inserted, a
five-axis processing, preferably using a five-axis CNC milling
machine, is used to fully automatically mill off the inserted
sleeve 11 at its crestal end (on the top in FIG. 3). The five-axis
CNC milling machine receives the data for this process from an
electronic memory, in which the data of a scan of the oral space of
the patient are stored. The situation in the oral space and, in
particular, the position and orientation of all dental implants in
the jaw of the patient to be treated are recorded at high accuracy
during the scan (inaccuracy of less than 10 .mu.m).
[0088] Whereas the model 16 was produced through rapid prototyping
from the same data but at lower accuracy, ablation of the sleeves
11 through the more accurate five-axis processing allows laboratory
analogues to be produced whose position and orientation correspond
to the situation, in particular the position and orientation of the
dental implants, in the oral space of the patient, preferably at an
accuracy of at least 10 .mu.m. Especially where a superstructure is
to be attached to multiple dental implants, the high accuracy of
the present method is advantageous in order to prevent any tension
exerted on the jaw by superstructures that have not been fabricated
at sufficient accuracy in concert with the dental implants.
[0089] FIG. 5 shows a schematic perspective view of an alternative
laboratory analogue 21 for implementing a method according to the
invention. The laboratory analogue 21 has a cylindrical base 2
whose upper crestal end has a depression 23 provided on it. The
depression 23 serves to accommodate an abutment for producing a
superstructure to be inserted, for example, as a dental restoration
or as a superstructure in the oral space of a patient on a dental
implant having the same crestal end. A hole having an internal
thread (not shown) for attachment of the abutment is situated in
the depression 23. An accommodation opening 25 is provided in the
cylinder jacket of the laboratory analogue 21 and opens into a
cylindrical depression in the base 2 of the laboratory analogue
21.
[0090] The laboratory analogue 21 is a standard part, in which the
position and orientation of the accommodation opening 25 and of the
cylindrical depression in the jacket of the base 2 were fabricated
at high accuracy, for example an accuracy of at least 6 .mu.m.
[0091] FIG. 6 shows a schematic perspective and transparent partial
view of a jaw model 26 having a feed-through 28 for fixation of a
laboratory analogue 21 according to FIG. 5 in a recess 7 of the
model 26 for implementing a method according to the invention. The
feed-through 28 has the same geometry as the cylindrical depression
in the jacket of the base 2 of the laboratory analogue 21. The
laboratory analogue 21 is to be inserted from above into the recess
7 such that the cylindrical depression in the jacket of the base 2
extends the feed-through 28. Subsequently, the laboratory analogue
21 can be affixed with a pin (not shown) that matches the geometry
of the feed-through 28 and of the cylindrical depression in the
jacket of the base 2 through inserting the pin through the
feed-through 28 into the cylindrical depression in the cylinder
jacket of the base 2.
[0092] A marking can be provided on the laboratory analogue 21 to
indicate the position of the opening 25 in order to make it easier
for the dental technician to insert the laboratory analogue 21.
[0093] The model 26 is preferably initially fabricated without the
feed-through 28 by means of rapid prototyping. This renders the
accuracy of the model 26 to be approximately 60 .mu.m. In this
context, the accuracy of the data used for fabrication of the model
26 by rapid prototyping is higher, for example up to 3 .mu.m. The
model 26 without feed-through 28 is then clamped and fixed in place
in a bracket of a drilling machine or other facility for generating
a feed-through 28 at high accuracy that allows for drilling at high
accuracy, for example an accuracy at the level of the accuracy of
the position of the cylindrical depression in the jacket of the
base 2 in the laboratory analogue 21 (6 .mu.m). A computer uses the
data to calculate the position of the bore hole in order to
position the laboratory analogue 21 upon fixation with the pin such
that the position of the crestal end of the laboratory analogue 21
coincides with the position of the crestal end of the dental
implant in the jaw of the patient. And lastly, the feed-through 28
in the model 26 is generated.
[0094] Likewise, any other feed-throughs in the model 26 (not
shown), if applicable, are generated and the position and
orientation of the crestal ends of the laboratory analogues 21 with
respect to each other is thus adjusted appropriately such that
these coincide with the position and orientation of the crestal
ends of all dental implants in the jaw of the patient.
[0095] FIG. 7 shows a schematic perspective view of another
laboratory analogue 31 for implementing a method according to the
invention. The laboratory analogue 31 is a cylindrical body having
a groove 35. A hole 4 having an internal thread is provided along
the cylinder axis of the laboratory analogue 31. An abutment can be
screwed into the internal thread. The crestal end in FIG.
[0096] 7 is situated on the bottom, unlike in FIGS. 1, 3, and
5.
[0097] FIG. 8 shows a schematic cross-sectional view of a detail of
a jaw model 36 according to the invention. A recess 7 for
accommodation of a laboratory analogue 31 is arranged in the model
36. As a matching counterpart to the laboratory analogue 31
according to FIG. 7, the model 36 comprises a projection 38 that
fits in the groove 35 of the laboratory analogue 31 and thus
unambiguously defines the position of the laboratory analogue
31.
[0098] The model 36 comprises gingiva 45, alveolar ridge 46, and
teeth 47, or parts thereof to be exact. The model 36 is fabricated
from plastic material and has been generated based on data obtained
using a stereolithographic method by performing a scan of an oral
space of a patient. The opposite part of the jaw (not shown) can
also be part of the model 36 in order to be able to represent the
situation upon mastication, for example with the mouth closed.
Accordingly, the model 36 can continue not only on the right and
left, as indicated through the dashed lines.
[0099] The model 36 comprises the recess 7 in the form of a
cylindrical hole in a site between the teeth 47. The cylindrical
rotational symmetry of the recess 7 is broken through the
projection 38. This secures the exact position of a laboratory
analogue 31, such as the one according to FIG. 7, in the model 36,
against both rotation and positional change.
[0100] For a laboratory analogue 21 and/or a sleeve 11 as shown in
FIG. 3 or 5, the recess 7 in a matching model would be built as a
cylindrical hole with a flat portion or a feed-through through the
gingiva 45 at the alveolar ridge 46, which would keep the
laboratory analogue 21 and/or sleeve 11 in position safe against
rotation. The advantage of the structure is that the laboratory
analogue 31 can be taken out quickly, whereas the laboratory
analogue 21 according to FIG. 5 can be fixed in place better and
more accurately.
[0101] Another particularly preferred exemplary embodiment of a
method according to the invention is illustrated in the following.
Measurements of the oral space are made for production of a
well-fitting dental restoration. For this purpose, a
three-dimensional image of the oral space, and/or, in particular,
the respective part of the jaw, is recorded. These data are then
stored in a memory of a computer. During the recording, the
positions of all dental implants in the jaw of the patient are
defined accurately by inserting standard positional markers in the
dental implants for the scan, whereby the markers can be identified
unambiguously during the scan and render the position and
orientation of the dental implants exactly defined by the scan.
[0102] These data are used to calculate a virtual three-dimensional
CAD model of the jaw or of part of the jaw in a computing unit of
the computer. Different recesses 7 or basic recess shapes are
stored in the memory of the computer and are assigned to different
laboratory analogues 1, 21, 31 and/or sleeves 11. The computer
calculates how the various recesses 7 might be arranged in the
model 6, 16, 26, 36. The most stable or most reasonable variant is
selected or the most stable or most reasonable variants are
proposed by means of a display facility. A criterion in this
context can be, for example, how thick is the wall of the model 6,
16, 26, 36 in the region of the recess 7 in the alveolar ridge 46
for the various recesses 6, 16, 26, 36 or which is the most
well-suited laboratory analogue 1, 21, 31 and/or sleeve 11 for the
position in the jaw.
[0103] Alternatively, the user can select from all stored recesses
7 the one deemed most suitable. The invention can just as well
provide the computer to indicate, based on a calculation, that a
selected recess 7 is not feasible or not reasonable, for example is
not stable enough, if applicable. Moreover, it is feasible that
only one recess 7 is stored for a particular type of laboratory
analogues 1, 21, 31 and/or sleeves 11.
[0104] Subsequently, the recess 7 selected by means of an input
facility or the pre-determined recess 7 is combined with the
virtual model of the jaw. For this purpose, the recess 7 is
included in the calculation of the virtual model as a surface of
the virtual model at the respective site at which the dental
implant is arranged in the jaw of the patient. The new virtual
model is then used to generate an actual model 6, 16, 26, 36 using
known methods, such as, for example, rapid prototyping methods. For
this purpose, the computer is connected to a manufacturing facility
designed for implementing methods of this type.
[0105] Just as well, the recess 7 may not yet be included in the
model 6, 16, 26, 36 or may be designed as a precursor, that is too
small in size. The final shaping of the recess 7 is effected using
a more accurate manufacturing method than rapid prototyping.
Conceivable in this regard are five-axis processing methods that
utilize the higher accuracy of the scanning data to generate the
recess 7 and its position and orientation to each other at higher
accuracy. Accordingly, recess 7 is subjected to precision
processing such that the position, orientation, and depth of the
recess 7 in the model and, if applicable, of the recesses with
respect to each other are fabricated appropriately such that the
crestal ends of the inserted laboratory analogues 1, 21, 31
coincide exactly with the orientations and positions of the crestal
ends of the dental implants in the jaw and, if applicable, of the
dental implants with respect to each other.
[0106] Accordingly, either the recess 7 can then be processed with
a precision tool, for example through a five-axis processing, based
on the more accurate scanning data or, alternatively, a
feed-through can be drilled accurately in order to define the
position and orientation of a prefabricated laboratory analogue 1,
21, 31 at high accuracy. Another alternative allows a sleeve 11
inserted in the recess 7 to be ablated, additionally or
alternatively, with a precision tool, for example through a
five-axis processing, based on the more accurate scanning data, in
order to produce the exactly correct length and arrangement of the
laboratory analogue 1, 21, 31 thus generated.
[0107] The actual dental restoration can then be generated on the
superstructure 3 of the laboratory analogue 1, 21, 31 in a
realistic environment and in accurate position. Whenever the
laboratory analogue 1, 21, 31 or the sleeve 11 is removed from or
re-inserted into the model 6, 16, 26, 36, it will be situated in
the same position in the jaw model 6, 16, 26, 36. This ensures that
the dental restoration has the exactly correct shape. Moreover, the
dental restoration will also be arranged in the same position in
the oral space of the patient on the actual dental implant such
that a particularly good fit is guaranteed.
[0108] The features of the invention disclosed in the preceding
description and in the claims, figures, and exemplary embodiments,
can be essential for the implementation of the various embodiments
of the invention both alone and in any combination.
[0109] It will be appreciated by those skilled in the art that
changes could be made to the embodiments described above without
departing from the broad inventive concept thereof. It is
understood, therefore, that this invention is not limited to the
particular embodiments disclosed, but it is intended to cover
modifications within the spirit and scope of the present invention
as defined by the appended claims.
* * * * *