U.S. patent application number 14/461281 was filed with the patent office on 2014-12-04 for prosthodontic and orthodontic apparatus and methods.
This patent application is currently assigned to Align Technology, Inc.. The applicant listed for this patent is Align Technology, Inc.. Invention is credited to Carlos Alvarez, Jihua Cheng, Ali Kakavand, Eric Kuo, Vadim Matov.
Application Number | 20140358497 14/461281 |
Document ID | / |
Family ID | 39590441 |
Filed Date | 2014-12-04 |
United States Patent
Application |
20140358497 |
Kind Code |
A1 |
Kuo; Eric ; et al. |
December 4, 2014 |
PROSTHODONTIC AND ORTHODONTIC APPARATUS AND METHODS
Abstract
System and method for developing a treatment plan for achieving
a treatment goal including creating a virtual model of a dental
patient's dentition; transforming the virtual model of the
dentition using virtual prosthodontics to facilitate achievement of
the treatment goal; transforming the virtual model of the dentition
using virtual orthodontics to facilitate achievement of the
treatment goal; iterating on the transforming steps until
substantially achieving the treatment goal; and generating an
orthodontic treatment plan and a prosthodontic treatment plan based
upon the substantially achieved treatment goal
Inventors: |
Kuo; Eric; (San Jose,
CA) ; Cheng; Jihua; (Cupertino, CA) ; Matov;
Vadim; (San Jose, CA) ; Alvarez; Carlos;
(Gilroy, CA) ; Kakavand; Ali; (San Carlos,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Align Technology, Inc. |
San Jose |
CA |
US |
|
|
Assignee: |
Align Technology, Inc.
San Jose
CA
|
Family ID: |
39590441 |
Appl. No.: |
14/461281 |
Filed: |
August 15, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12682225 |
Mar 16, 2011 |
8807999 |
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PCT/US2007/081262 |
Oct 12, 2007 |
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14461281 |
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Current U.S.
Class: |
703/1 |
Current CPC
Class: |
A61C 7/08 20130101; A61C
13/0004 20130101; G16H 50/50 20180101; G06F 30/00 20200101; A61C
7/002 20130101; A61C 9/004 20130101 |
Class at
Publication: |
703/1 |
International
Class: |
G06F 19/00 20060101
G06F019/00; A61C 9/00 20060101 A61C009/00; G06F 17/50 20060101
G06F017/50; A61C 7/00 20060101 A61C007/00 |
Claims
1-68. (canceled)
69. A method for generating dental information of a patient
comprising: creating a virtual model of a patient's dentition in a
first configuration, the dentition including at least one tooth
having a reference volume; generating a model volume created as the
at least one tooth is moved from the first configuration to a
second configuration; and subtracting the reference volume from the
model volume to yield a build-up volume.
70. The method of claim 69, wherein the virtual model is created in
a prepared configuration.
71. The method of claim 70, further comprising determining a
removed volume by subtracting a volume of the dentition in the
prepared configuration from the reference volume.
72. The method of claim 71, further comprising determining a
restoration volume by combining the removed volume and the build-up
volume.
73. The method of claim 70, further comprising: transforming the
virtual model of the patient's dentition from the first
configuration into a first intermediate configuration; generating a
first intermediate model volume created as the at least one tooth
is moved from the first intermediate configuration to the second
configuration; subtracting the reference volume from the first
intermediate model volume to yield a first intermediate build-up
volume; and determining if the effect of the transforming step on
the first intermediate build-up volume is a desired effect.
74. The method of claim 73, further comprising: determining a
removed volume by subtracting a volume of the dentition in the
prepared configuration from the reference volume; and determining a
restoration volume by combining the removed volume and the first
intermediate build-up volume.
75. The method of claim 73, further comprising: transforming the
virtual model of the patient's dentition from the first
configuration into a second intermediate configuration; generating
a second intermediate model volume created as the at least one
tooth is moved from the second intermediate configuration to the
second configuration; subtracting the reference volume from the
second intermediate model volume to yield a second intermediate
build-up volume; and determining if the effect of the transforming
step on the second intermediate build-up volume is a desired
effect.
76. The method of claim 75, further comprising: determining a
removed volume by subtracting a volume of the dentition in the
prepared configuration from the reference volume; and determining a
restoration volume by combining the removed volume and the second
intermediate build-up volume.
77. The method of claim 69, wherein generating the model volume
comprises: determining the volume of the virtual space occupied by
the at least one tooth as the at least one tooth is moved from the
first configuration to the second configuration.
78. The method of claim 69, further comprising: verifying whether
the build-up volume overlaps at least one of a virtual tooth volume
and a virtual veneer volume of a neighboring tooth.
79. The method of claim 78, further comprising: deforming the
build-up volume to resolve the overlap.
80. The method of claim 69, wherein creating the virtual model of a
patient's dentition comprises generating a reference contour mesh
crown representing a surface boundary of the at least one
tooth.
81. The method of claim 80, wherein generating the model volume
comprises: calculating a virtual space occupied by the reference
contour mesh crown as the reference contour mesh crown is moved
from the first configuration to the second configuration.
82. A system for generating dental information of a patient
comprising: a processor configured to: create a virtual model of a
patient's dentition in a first configuration, the dentition
including at least one tooth having a reference volume; generate a
model volume created as the at least one tooth travels from the
first configuration to a second configuration; and subtract the
reference volume from the model volume to yield a build-up
volume.
83. The system of claim 82, wherein the processor is further
configured to create a virtual model of a patient's dentition in a
prepared configuration.
84. The system of claim 83, wherein the processor is further
configured to determine a removed volume by subtracting a volume of
the dentition in the prepared configuration from the reference
volume.
85. The system of claim 84, wherein the processor is further
configured to determine a restoration volume by adding the removed
volume and the build-up volume.
86. The system of claim 82, wherein the processor is further
configured to: transform the virtual model of the patient's
dentition from the first configuration into a first intermediate
configuration; generate a first intermediate model volume created
as the at least one tooth travels from the first intermediate
configuration to the second configuration; and subtract the
reference volume from the first intermediate model volume to yield
a first intermediate build-up volume.
87. The system of claim 86, wherein the processor is further
configured to: transform the virtual model of the patient's
dentition from the first configuration into a second intermediate
configuration; generate a second intermediate model volume created
as the at least one tooth travels from the second intermediate
configuration to the second configuration; and subtract the
reference volume from the second intermediate model volume to yield
a second intermediate build-up volume.
88. The system of claim 82, wherein the processor is further
configured to: verify whether the build-up volume overlaps at least
one of a virtual tooth volume and a virtual veneer volume of a
neighboring tooth.
89. The system of claim 88, wherein the processor is further
configured to: deform the build-up volume to resolve the
overlap.
90. The system of claim 85, further comprising: a mechanism for
displaying a virtual representation selected from the group
consisting of at least one of a virtual representation of the first
configuration, a virtual representation of the build-up volume, a
virtual representation of the restoration volume, a virtual
representation of the removed volume, a virtual representation of
the second configuration, a virtual representation of the prepared
configuration, and a virtual representation of the reference
volume.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is continuation application of co-pending
application Ser. No. 12/682,225 filed on Mar. 16, 2011; which is a
national phase filing, under 35 U.S.C. .sctn.371(c), of
International Application No. PCT/US2007/081262, filed Oct. 12,
2007, the disclosures of which are incorporated herein by reference
in their entireties.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates to prosthodontic and
orthodontic dental procedures.
[0004] 2. Related Art
[0005] Orthodontics is a dental specialty concerned with correcting
irregularities in a patient's dentition, such as malocclusion.
Orthodontics generally involves the realignment and/or
repositioning of a patient's teeth. The corrected alignment and/or
position improve the function and appearance of the teeth.
[0006] Prosthodontics is a dental specialty concerned with
correcting irregularities in a patient's dentition, such as
missing, misshaped, malformed, or maloccluded teeth. Whereas
orthodontics generally involves realignment and/or repositioning of
a patient's teeth, prosthodontics generally involves reshaping a
patient's teeth by grinding or cutting and/or building up portions
of the teeth with biocompatible dental materials. For example, a
prosthodontic procedure may involve the placement of one or more
dental restorations, such as crowns, bridges, inlays, and/or
veneers. Prosthodontics also corrects for improper tooth color and
shape, which orthodontics alone cannot correct.
SUMMARY
[0007] The embodiments of the present prosthodontic and orthodontic
apparatus and methods have several features, no single one of which
is solely responsible for their desirable attributes. Without
limiting the scope of the present apparatus and methods as
expressed by the claims that follow, their more prominent features
will now be discussed briefly. After considering this discussion,
and particularly after reading the section entitled "Detailed
Description", one will understand how the features of the present
embodiments provide advantages, which include the ability to
control various restorative parameters during the stages of
planning and delivering orthodontic and prosthodontic treatment,
the ability to iterate during the planning stages to arrive at
various treatment goals and to then select a most desired treatment
goal, reduced tooth material removed, preservation of future
options for orthodontic and/or prosthodontic procedures, improved
prosthodontic outcomes, assisting a dental professional in
precisely identifying areas of a patient's dentition to be removed
during a prosthodontic procedure, and assisting the dental
professional in verifying whether he or she has removed enough
tooth material to properly seat dental restorations.
[0008] One aspect of the present apparatus and methods includes the
realization that in a prosthodontic procedure it is desirable to
control restorative parameters so that they fall within desired
ranges in the final restorative outcome. A patient typically has
one or more goals that he or she wants to achieve through the
prosthodontic procedure. By controlling these parameters both
during the planning stages and during the delivery of
orthodontia/prosthodontia, the patient is more likely to his or her
restorative treatment goals.
[0009] Another aspect of the present apparatus and methods includes
the realization that in a prosthodontic procedure it is desirable
to remove as little healthy tooth material as necessary to ensure a
structurally sound final restoration. The removal process is
irreversible and potentially uncomfortable for the patient.
Furthermore, subsequent dental work on the same tooth typically
requires further removal of natural tooth structure. Therefore, it
is desirable to remove as little natural tooth structure as
necessary, since the options for future modifications of the
patient's dentition become more limited as more tooth material is
eliminated. Excessive removal may also lead to complications, such
as creating a need for endodontic treatment (root canal treatment),
and compromised retention of the dental restoration.
[0010] Another aspect of the present apparatus and methods includes
the realization that in a prosthodontic procedure there is a
prognosis for each patient based at least in part on the beginning
configuration of that patient's dentition. Thus, for patients with
severely maloccluded teeth, the restorative prognosis may be poor
due at least in part to the severity of the malocclusion. By
treating the patient's dentition first with orthodontia prior to
performing the prosthodontic procedure, the prognosis for that
patient may be significantly improved, because the new tooth
positions may require less structural change, and enable more
enhanced restorative design.
[0011] Another aspect of the present apparatus and methods includes
the realization that when placing a preparation guide over a
patient's dentition prior to tooth modification, protruding areas
of the teeth (areas that are to be removed during the preparation)
may prevent the guide from being seated properly unless the areas
are actually removed. Thus, it is difficult for the dental
professional to identify with precision, areas of the teeth that
are to be removed without actually cutting the teeth. It is also
difficult for the dental professional to precisely verify whether
he or she has removed enough tooth material to properly create the
desired dental restoration(s) to be placed. Therefore, it would be
advantageous if the dental professional had available a guide that
could be used to measure for adequate preparation clearance while
at the same time avoiding protruding areas of the patient's teeth
that would prevent the guide from being seated properly even in
advance of any tooth modification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The disclosed embodiments of the present prosthodontic and
orthodontic apparatus and methods will now be discussed in detail
with an emphasis on highlighting the advantageous features. These
embodiments depict the novel and non-obvious apparatus and methods
shown in the accompanying drawings, which are for illustrative
purposes only. These drawings include the following figures, in
which like numerals indicate like parts:
[0013] FIG. 1 is a table rating various orthodontic/prosthodontic
treatment options against restorative parameters;
[0014] FIG. 2 is a schematic illustration of two teeth in a
pretreatment configuration;
[0015] FIG. 3 is a schematic illustration of the teeth of FIG. 2 in
a post-treatment configuration according to one example
prosthodontic treatment plan;
[0016] FIG. 4 is a schematic illustration of the teeth of FIG. 2 in
a post-treatment configuration according to another example
prosthodontic treatment plan;
[0017] FIG. 5 is a schematic illustration of the teeth of FIG. 2 in
a post-treatment configuration according to one example
orthodontic/prosthodontic treatment plan;
[0018] FIG. 6 is a schematic illustration of the teeth of FIG. 2 in
a post-treatment configuration according to another example
orthodontic/prosthodontic treatment plan;
[0019] FIG. 7 is a schematic illustration of the teeth of FIG. 2 in
a post-treatment configuration according to another example
orthodontic/prosthodontic treatment plan;
[0020] FIG. 8 is a schematic illustration of the teeth of FIG. 2 in
a post-treatment configuration according to one example orthodontic
treatment plan;
[0021] FIG. 9 is a flowchart illustrating steps that may be
performed in certain embodiments of the present methods;
[0022] FIG. 10 is a perspective view of one embodiment of an
aligner that may be used in connection with certain embodiments of
the present apparatus and methods;
[0023] FIG. 11 is a flowchart illustrating steps that may be
performed in certain embodiments of the present methods;
[0024] FIG. 12 is a front elevation view of a tooth in a beginning
configuration;
[0025] FIG. 13 is a front elevation view of the tooth of FIG. 12
superimposed with a desired final configuration for the tooth,
according to one embodiment of the present methods;
[0026] FIG. 14 is a front elevation view of the tooth of FIG. 12
superimposed with a desired final configuration for the tooth,
according to one embodiment of the present methods;
[0027] FIG. 15 is a front elevation view of the tooth of FIG. 12
and one embodiment of the present prosthodontic apparatus;
[0028] FIG. 16 is a front elevation view of the tooth of FIG. 12
and one embodiment of the present prosthodontic apparatus,
illustrating the step of removing a portion of the tooth that
extends beyond the apparatus;
[0029] FIG. 17 is a front elevation view of the tooth of FIG. 12
after it has been prepared according to one embodiment of the
present methods;
[0030] FIG. 18 is a front elevation view of the tooth of FIG. 12
and a dental restoration placed in accordance with one embodiment
of the present methods;
[0031] FIG. 19 is a flowchart illustrating steps in another
embodiment of the present methods;
[0032] FIG. 20 is a graph representing the start and stop points
which yield the least amount of tooth mass removal and/or mass
build-up over a given amount of available treatment time;
[0033] FIG. 21 is a flowchart illustrating a process for simulating
the creation of veneer models using orthodontic and prosthodontic
techniques in accordance with one embodiment of the present
invention;
[0034] FIGS. 22A and 22B are simplified views of a dental arch in a
pre-treatment configuration and in a final configuration in
accordance with one embodiment of the present invention,
respectively;
[0035] FIG. 23 is a flowchart illustrating steps in an embodiment
of the process of FIG. 21;
[0036] FIG. 24 shows a simplified side view of a tooth in an
Initial configuration and a Prepared configuration in accordance
with one embodiment of the present invention;
[0037] FIG. 25 shows a simplified side view and a top view of the
sweep volume of a Prepared tooth configuration in accordance with
one embodiment of the present invention; and
[0038] FIG. 26 is a flowchart illustrating a process for preparing
an actual restoration in accordance with the present invention.
DETAILED DESCRIPTION
[0039] It should be understood that the techniques of the present
invention may be implemented using a variety of technologies. For
example, methods described herein may be implemented in software
executing on a computer system, or implemented in hardware using
either a combination of microprocessors or other specially designed
application specific integrated circuits, programmable logic
devices, or various combinations thereof. In particular, methods
described herein may be implemented by a series of
computer-executable instructions residing on or carried by a
suitable computer-readable medium. Suitable computer-readable media
may include volatile memory (e.g., RAM) and/or non-volatile memory
(e.g., ROM, disk).
[0040] Certain embodiments of the present prosthodontic and
orthodontic apparatus and methods advantageously combine the
benefits of orthodontic treatment with a prosthodontic procedure to
enhance the final outcome of the procedure. The embodiments produce
a healthy-looking smile with a reduced amount of tooth structure
removed as compared to a traditional prosthodontic procedure with
no orthodontia. The reduction in tooth structure removed reduces
complications that can arise from over-reduction of teeth, such as
sensitivity. It also helps to ensure that the reduction may be
performed in an accurate, reproducible manner. Further, the options
for future modifications of the patient's dentition are increased,
since a greater proportion of the patient's original dentition
remains after the procedure has been completed.
[0041] Certain other embodiments of the present apparatus and
methods advantageously enable one or more restorative parameters to
be controlled during a prosthodontic procedure. Upon identifying
one or more parameters of interest, a dental professional can
iterate processes of virtual orthodontia and virtual prosthodontia
to observe whether each iteration produces a desired outcome for
the parameter(s) of interest. The dental professional may perform
the iterations together with the patient. The parameters of
interest may include, for example, time of treatment, volume of
tooth structure removed, final aesthetics and/or alignment of
lingual tooth surfaces or other parameters.
[0042] Certain other embodiments of the present apparatus and
methods advantageously assist a dental professional in identifying
areas of a patient's dentition to be removed during a prosthodontic
procedure. The present embodiments also assist the dental
professional in verifying whether he or she has removed enough
tooth material to properly create dental restoration(s) that are to
be placed. The prosthodontic methods described herein may be
performed on a patient's entire dentition or on just one tooth. For
simplicity, however, some of the present apparatus and methods are
shown in the figures with reference to only a single tooth.
[0043] Certain other embodiments of the present apparatus and
methods advantageously assist a dental professional in forming an
orthodontic treatment plan oriented on optimal veneer usage. These
embodiments assist the dental professional in quantifying
parameters used to properly create dental restoration(s) that are
to be placed.
Treatments
[0044] Embodiments of the present methods may begin when a patient
first consults a dental professional (which may include, but is not
limited to, a dentist, an orthodontist, a lab technician, a dental
product provider, a dental service provider and the like) regarding
an orthodontic procedure and/or a prosthodontic procedure. During
the initial consultation, the dental professional and the patient
may discuss the patient's treatment goal(s) and any constraints
that might limit the range of available treatment options. For
example, the patient may desire to have his or her smile enhanced
prior to his or her wedding, but the patient may not consult the
dental professional until six months prior to the wedding. In such
a situation, the timeframe for treatment is limited, and an
appropriate orthodontic/prosthodontic treatment plan must be set to
fit within the timeframe.
[0045] In the table of FIG. 1, the left-hand column lists seven
orthodontic/prosthodontic treatment options represented by the
letters A-G. Options A-G are schematically illustrated in FIGS.
2-8, which are discussed in detail below. The top row of the table
lists four restorative parameters that may be of interest to the
patient. The exemplary four restorative parameters are: time
required to complete the orthodontic/prosthodontic treatment,
reduction in volume of tooth structure resulting from prosthodontic
treatment, final aesthetics upon completion of treatment (including
teeth color, realistic thickness of teeth and the like), and
alignment of lingual tooth surfaces (on tongue side of teeth) upon
completion of treatment. As explained in detail below, the table
assesses each of the treatment options by assigning qualitative
values to each of the restorative parameters for that treatment
option. Those of ordinary skill in the art will appreciate that
there may be additional restorative parameters not listed in FIG. 1
that may be of interest to some patients. Accordingly, the listed
parameters should not be interpreted as limiting the scope of the
present embodiments.
[0046] In FIG. 1, each of the orthodontic/prosthodontic treatment
options is rated against the four listed parameters. To assess a
given treatment option, the dental professional and/or patient
locates that option in the leftmost column and reads across the
table. The symbols appearing in each column indicate whether the
treatment option produces a positive outcome or a negative outcome
for the parameter of that column. If a treatment option produces a
positive outcome for a given parameter, one or more + signs appear
in the column for that parameter. If a treatment option produces a
negative outcome for a given parameter, one or more - signs appear
in the column for that parameter. Multiple + or - signs indicate
that that parameter is particularly positive or particularly
negative for that treatment option. If a 0 appears in a column,
then that parameter is considered neutral with respect to that
treatment option.
[0047] FIG. 2 schematically illustrates a first tooth X and a
second tooth Y in a pretreatment configuration, while FIGS. 3-8
illustrate the same teeth in various post-treatment configurations.
In FIGS. 2-8, the illustrated teeth are molars, and the cuspal
(chewing) surface of each molar faces the viewer. The lingual
(tongue side) surface of each tooth faces downward, and the buccal
(opposite the tongue side) surface of each tooth faces upward.
[0048] In the pretreatment configuration of FIG. 2, tooth X is
positioned closer to the tongue than tooth Y. Thus, neither the
lingual surfaces nor the buccal surfaces of the teeth are aligned.
Further, a portion of tooth Y is overlapping a portion of tooth X.
Thus, to align the lingual and buccal surfaces of the teeth, either
the teeth must first be moved away from each other, or the
overlapping portions of one or both teeth must be removed.
[0049] FIG. 1 includes option A, which represents no orthodontic or
prosthodontic treatment and provides a baseline from which to
relatively measure other outcomes. Thus, the teeth remain as they
appear in FIG. 2. Referring to the table in FIG. 1 and reading
across the first row, option A produces a very strongly positive
outcome (+++) for the time required to complete the treatment,
because there is no treatment. Option A also produces a very
strongly positive outcome (+++) for reduction in volume of tooth
structure, because no tooth structure is removed. Finally,
treatment option A produces strongly negative outcomes (---) for
both final aesthetics and alignment of lingual tooth surfaces,
because no improvements are made in these areas.
[0050] FIG. 3 schematically illustrates one treatment plan that
involves only prosthodontics. To transform the teeth from the
configuration of FIG. 2 into the configuration of FIG. 3, the
overlapping portion of tooth Y is cut or ground away, and a veneer
is applied to the buccal surface of tooth X. In order to firmly
secure the veneer to the tooth, small portions on either side of
tooth X are removed to form butt joints with the veneer.
[0051] Referring to the table in FIG. 1 and reading across the
second row, treatment option B produces a strongly positive outcome
(++) for the time required to complete the treatment, because the
treatment involves only prosthodontia, which may be completed in a
much shorter timeframe than orthodontia. However, treatment option
B produces a negative outcome (-) for reduction in volume of tooth
structure, since the overlapping portion of tooth Y is removed and
small portions on either side of the tooth X are removed to form
the butt joints. Treatment option B produces a more negative
outcome (--) for final aesthetics, since a very thick veneer is
added to tooth X, and since there is no matching veneer added to
tooth Y. Thus, the color of tooth Y is not improved, and there may
be some color contrast between the buccal surfaces of teeth X and
Y. Finally, treatment option B produces a very strong negative
outcome (---) for alignment of lingual tooth surfaces, the
misalignment of the lingual surfaces is not corrected at all.
[0052] FIG. 4 schematically illustrates another treatment plan that
also involves only prosthodontics. To transform the teeth from the
configuration of FIG. 2 into the configuration of FIG. 4, the
overlapping portion of tooth Y is ground away, and a veneer is
applied to the buccal surface of tooth X. In this embodiment, a
veneer is also applied to the buccal surface of tooth Y. As in
treatment option B above, small portions on either side of tooth X
are removed to form butt joints with the veneer. To secure the
veneer to tooth Y, a thin wall of the buccal surface of tooth Y is
removed in addition to small portions on either side of tooth Y for
butt joints.
[0053] Referring to the table in FIG. 1 and reading across the
third row, treatment option C produces a strong positive outcome
(++) for the time required to complete the treatment, because the
treatment involves only prosthodontia. Treatment option C produces
a strong negative outcome (--) for reduction in volume of tooth
structure, because not only is the overlapping tooth structure of
tooth Y removed, but tooth structure is removed from tooth X and
tooth Y to form butt joints and to make room for the veneer on
tooth Y. Treatment option C produces a neutral outcome (0) for
final aesthetics, because although there is a very thick veneer
added tooth X, the color of both teeth are improved because of the
matching veneers. Finally, like treatment option B treatment option
C also produces a very strong negative outcome (---) for alignment
of lingual tooth surfaces.
[0054] In order to arrive at the best possible outcome for a
patient's specific condition or treatment requirements, trade-offs
may be made between each of the restorative parameters. It is
apparent that for some situations where, for example, aesthetics
and lingual alignment are important parameters, and particularly
where it is desired to minimize the amount of tooth reduction, some
combination of orthodontics and prosthodontics may be
indicated.
[0055] FIG. 5 schematically illustrates another treatment plan that
involves both orthodontics and prosthodontics. To transform the
teeth from the configuration of FIG. 2 into the configuration of
FIG. 5, the overlapping portion of tooth Y is ground away, and
tooth X is moved forward (away from the tongue). However, tooth X
is only moved forward through the distance d, such that while
alignment of the buccal and lingual surfaces of the teeth is
improved, it is not made perfect. In treatment option D veneers are
also applied to the buccal surfaces of teeth X and Y.
[0056] Referring to the table in FIG. 1 and reading across the
fourth row, treatment option D produces a positive outcome (+) for
the time required to complete the treatment, because although the
treatment involves orthodontia, the treatment nevertheless takes
less time than a treatment option that involves more movement of
tooth X. Treatment option D produces strong negative outcome (--)
for reduction in volume of tooth structure, because not only is the
overlapping tooth structure of tooth Y removed, but tooth structure
is removed from tooth X and tooth Y to form butt joints and to make
room for the veneer on tooth Y. Treatment option D produces a
positive outcome (+) for final aesthetics, since, due to the
movement of tooth X, relatively thin veneers are added to both
teeth. Finally, treatment option D produces a positive outcome (+)
for alignment of lingual tooth surfaces, because the alignment is
improved over that of the pretreatment configuration.
[0057] FIG. 6 schematically illustrates another treatment plan that
also involves both orthodontics and prosthodontics. To transform
the teeth from the configuration of FIG. 2 into the configuration
of FIG. 6, the overlapping portion of tooth Y is ground away, and
tooth X is moved forward (away from the tongue). In contrast to
treatment option D, tooth X is moved forward through the distance D
until the lingual surfaces of the teeth align. In treatment option
E, veneers are also applied to the buccal surfaces of teeth X and
Y.
[0058] Referring to the table in FIG. 1 and reading across the
fifth row, treatment option E produces a negative outcome (-) for
the time required to complete the treatment, because the treatment
involves orthodontia to move tooth X through a greater distance D
when compared to other treatment options. Treatment option E
produces a strong negative outcome (--) for reduction in volume of
tooth structure, because not only is the overlapping tooth
structure of tooth Y removed, but tooth structure is removed from
tooth X and tooth Y to form butt joints and to make room for
veneers on both tooth X and tooth Y. Treatment option E produces a
strong positive outcome (++) for final aesthetics, because thin
veneers are added to both teeth and both teeth appear to be of
normal thickness. Finally, treatment option E produces a strongly
positive outcome (++) for alignment of lingual tooth surfaces,
because the alignment is greatly improved over that of the
pretreatment configuration.
[0059] FIG. 7 schematically illustrates another treatment plan that
involves orthodontics and prosthodontics. To transform the teeth
from the configuration of FIG. 2 into the configuration of FIG. 7,
the teeth are moved away from one another (as represented by the
oppositely directed arrows on either side of the teeth) and tooth X
is moved forward (away from the tongue) through the distance D
until the buccal and lingual surfaces of the teeth align. However
after the teeth are moved, treatment option F includes adding
veneers to the buccal surfaces of tooth X and tooth Y.
[0060] Referring to the table in FIG. 1 and reading across the
sixth row, treatment option F produces a strong negative outcome
(--) for the time required to complete the treatment, because the
treatment involves orthodontia to move tooth X through a distance D
and to move tooth X away from tooth Y. Treatment option F produces
a very neutral outcome (0) for reduction in volume of tooth
structure, because only a small amount of tooth structure is
removed on from tooth X and tooth Y to form butt joins for the
veneers. Treatment option F produces a very strong positive outcome
(+++) for final aesthetics because the teeth are properly aligned,
the teeth appear to be of normal thickness and the veneers correct
any discoloration or misshapenness from the pretreatment
configuration. Finally, treatment option F produces a strong
positive outcome (++) for alignment of lingual tooth surfaces,
because the alignment is greatly improved over that of the
pretreatment configuration.
[0061] FIG. 8 schematically illustrates another treatment plan that
involves only orthodontics. To transform the teeth from the
configuration of FIG. 2 into the configuration of FIG. 8, the teeth
are moved away from one another (as represented by the oppositely
directed arrows on either side of the teeth) and tooth X is moved
forward (away from the tongue) through the distance D until the
buccal and lingual surfaces of the teeth align.
[0062] Referring to the table in FIG. 1 and reading across the
seventh row, treatment option G produces a strong negative outcome
(--) for the time required to complete the treatment, because the
treatment involves orthodontia to move tooth X through a distance D
and to move tooth X away from tooth Y. Treatment option G produces
a very strong positive outcome (+++) for reduction in volume of
tooth structure, because no tooth structure is removed. Treatment
option G produces a positive outcome (+) for final aesthetics
because the teeth are properly aligned and appear to be of normal
thickness. However, because no veneers are added to the teeth, any
discoloration or misshapenness from the pretreatment configuration
remains. Finally, treatment option G produces a strong positive
outcome (++) for alignment of lingual tooth surfaces, because the
alignment is greatly improved over that of the pretreatment
configuration.
[0063] While the examples described with respect to FIGS. 2-8
relate to two teeth, similar principals apply to other
configurations of maloccluded and misshapen teeth and apply to
patient with two or more maloccluded teeth.
[0064] After the initial consultation between the patient and the
dental professional, the dental professional and the patient may
develop an orthodontic treatment plan and/or a prosthodontic
treatment plan. The orthodontic treatment plan may transform the
patient's dentition from its beginning configuration to an
intermediate configuration, and the prosthodontic treatment plan
may transform the patient's dentition from the intermediate
configuration to a final configuration. The intermediate
configuration may also be referred to as an orthodontic treatment
goal, and the final configuration may also be referred to as a
restorative treatment goal.
[0065] With reference to FIG. 9, a computer-generated,
three-dimensional, virtual model of the patient's dentition in the
beginning configuration is created, as shown at step S10. Unlike
some 3-D educational software which show representative "typodont"
models for illustrative purposes, this model represents the
patient's actual dentition in a beginning configuration. The
virtual model may be generated prior to any tooth preparation, so
that the model represents the patient's dentition in a pretreatment
state. Some processes for making such a virtual model are described
in, for example, U.S. Patent Application Publication No. US
2006/0154207, published on Jul. 13, 2006 and in U.S. patent
application Ser. No. 11/678,749, filed on Feb. 26, 2007 by Kaza et
al. The entire disclosures of the '207 publication and the '749
application are hereby incorporated herein by reference.
[0066] With continued reference to FIG. 9, the virtual model of the
beginning configuration using virtual orthodontia may be
transformed to create a computer-generated, three-dimensional,
virtual model of the patient's dentition in an intermediate
configuration, as shown at step SI2. The virtual orthodontia may
include manipulation and movement of teeth in the virtual model.
The virtual model of the intermediate configuration may be
transformed using virtual prosthodontia to create a
computer-generated, three-dimensional, virtual model of the
patient's dentition in a desired final configuration, as shown at
step S14. The virtual prosthodontics may include one or more
modifications of the virtual model, such as tooth mass removal or
build-up and/or the placement of one or more dental restorations.
Those of ordinary skill in the art will appreciate that steps S12
and S14 may be performed in any order, and may even be performed
simultaneously. In addition, steps S12 and S14 may be iterated
upon. During each iterative step, the final model may be evaluated
and iterated again or finalized into a treatment plan. These
iterative steps are described in greater detail below with respect
to FIG. 11.
[0067] Finalizing a treatment plan may include setting the
intermediate and final configurations, as shown at step S16 in FIG.
9. Once these configurations are set, the orthodontic treatment
plan and the prosthodontic treatment plan are generated, as shown
at step SI8. The orthodontic treatment plan may transform the
dentition from the beginning configuration to the intermediate
configuration, and the prosthodontic treatment plan will transform
the dentition from the intermediate configuration to the final
configuration or restorative treatment goal.
[0068] Once the treatment plan is finalized, the next step in the
present method may be to deliver a course of orthodontic treatment
according to the orthodontic treatment plan, as shown at step S20
in FIG. 9. The orthodontia may proceed using any well-known
apparatus and methods, such as orthodontic brackets and wires
(braces). Alternatively, or in addition, the orthodontia may
include a series of plastic orthodontic appliances or aligners.
FIG. 10 illustrates one such aligner 50 that is adapted to fit over
a patient's lower arch 52. The aligners, each of which may be a
polymeric shell having a teeth-receiving cavity, are described in
detail in the '893 patent and the '807 patent, both of which are
incorporated herein by reference above. The patient wears the
series of aligners in order to achieve incremental repositioning of
individual teeth in his or her jaw.
[0069] The polymeric aligner 50 of FIG. 10 may be formed from a
thin sheet of a suitable elastomeric polymer, such as Tru-Tain
0.030'' thermal forming dental material, available from Tru-Tain
Plastics of Rochester, Minn. Other aligner materials can include,
but are not limited to polyester, polyurethane, polypropylene,
polycarbonate, poly-blend, and poly-laminates. Usually, no wires or
other structures are provided for holding the aligner in place over
the teeth, though it may be possible to incorporate auxiliary
devices such as wires, hooks, and elastics into the aligners to
assist in appliance retention. It is also possible to provide
individual anchor attachments directly on the teeth, with
corresponding receptacles or apertures in the aligner so that the
aligner can apply either a retentive or a supplemental force on the
tooth that would not be possible in the absence of such an
anchor.
[0070] The aligners are generated using data representing the
patient's teeth. The data may be from scans of dental impressions,
dental casts, and/or direct scans of the patient. Each polymeric
shell may be configured so that its tooth-receiving cavity has a
geometry corresponding to an incremental tooth arrangement intended
for the patient. The patient's teeth are repositioned from their
initial arrangement to the next incremental arrangement by placing
the aligners sequentially over the teeth. The patient wears each
aligner until the teeth have conformed to the position defined by
the aligner. At that point, the patient moves onto the next aligner
stage of the planned course of treatment and replaces the old
aligner with the next aligner in the series until the intended
treatment outcome is achieved. The course of treatment may require
a recalibration scan and additional aligners if the teeth do not
exactly track according to the design within the aligner. However,
because the aligners are removable and not bonded to the teeth, the
process is convenient and hygienic for the patient, generally more
so than traditional braces, which are affixed directly to the teeth
and not intended to be removed by the patient during the course of
treatment.
[0071] The polymeric shell can fit over any and typically all teeth
present in the upper or lower jaw. Often, only a select few of the
teeth are repositioned at a given time while remaining teeth
provide a base or an anchor region for holding the aligner in place
as the aligner applies a repositioning force against the tooth or
teeth to be repositioned. In many cases, all teeth may be
repositioned at some point during the treatment. In such cases, the
moved teeth may also serve as a base or anchor region for holding
the aligner.
[0072] Upon completion of the orthodontic treatment plan, a dental
professional may perform one or more prosthodontic procedures
according to the prosthodontic treatment plan. As part of the
prosthodontic procedure(s), the dental professional prepares the
necessary teeth by reducing the tooth surfaces as needed to ensure
proper retention, strength, and aesthetics for the final
restoration. The prepared teeth may require one or more provisional
restorations. In some situations, however, the final restoration(s)
may be immediately fabricated in the dental professional's office
and placed without the need for any provisionals. An example of an
immediate fabrication system is the Siriona CEREC.TM. milling
machine, which uses an in-office scan of the prepared dentition,
the creation of a virtual restoration over the preparation scan,
and the milling of a porcelain block according to the virtual
restoration in consideration of the preparation scan.
[0073] Prior to placing the dental restoration(s) on the patient's
dentition, at least one of tooth surface removal, cutting and/or
reshaping may be performed, as shown in step S22 in FIG. 9. The
removal/cutting/reshaping prepares the dentition to receive the
dental restoration(s). As discussed above, such preparation
generally involves the removal of at least a portion of a tooth,
its enamel and/or dentin, and some or all pre-existing restorations
on the tooth. The reshaping may also involve building up some areas
of the dentition using biocompatible materials such as composite,
fiberglass, carbon fiber, gold, amalgam, titanium, and/or stainless
steel. When removing tooth material to accommodate a dental
restoration, generally 1 mm of tooth material is removed to ensure
adequate restoration strength and desired aesthetics. However, as
those of ordinary skill in the art will appreciate more or less
tooth material may be removed.
[0074] During the steps of removal/cutting/reshaping, the accuracy
and design of the removal, cutting and/or reshaping may be
periodically verified. In one embodiment, one or more preparation
guides may be positioned over the patient's dentition. The
preparation guide, which resembles an aligner and is typically
manufactured in a similar way, may embody the final restorative
configuration. Clearances between teeth surfaces and the
preparation guide may be measured to verify that the desired
amounts of tooth surface have been removed. To determine whether
adequate tooth material has been removed, the guide may be seated
on the teeth and any interference between the tooth and the guide
may be removed. Once the guide is fully seated, the clearances
between the guide and the teeth are checked and additional tooth
material is removed until adequate clearances are achieved between
the inner surfaces of the guide and the surfaces of the teeth
receiving the final restoration(s).
[0075] After the desired amount of tooth material has been removed
in conjunction with the preparation guide, a provisional or final
restoration may be prepared and affixed on the patient's dentition,
as shown in step S24 in FIG. 9. An adhesive, such as dental cement,
may be used to affix the restoration on the teeth to prevent it
from leaking and/or dislodging.
[0076] As described above, in the foregoing methods at least some
of the steps may be performed in an iterative fashion, and may
include one or more sub-steps. The iteration enables a dental
professional and a patient to focus on one or more restorative
parameters that are of interest to the patient, and to control the
outcome of the treatment with respect to these parameters.
Therefore, prior to or during the present methods the dental
professional and the patient may identify one or more restorative
parameters that are of interest to the patient. As discussed above
with respect to FIG. 1, these parameters may include: treatment
time, volume of tooth structure removed, final aesthetics and/or
alignment of lingual tooth surfaces. Moreover, after creating a
virtual model of the patient's dentition in the beginning
configuration (step S10, FIG. 11), the dental professional may
transform the virtual model to create virtual models representing
the desired intermediate configuration (SI2) and final
configuration (SI4). In addition, at step S26 the dental
professional may evaluate the one or more restorative parameters of
interest, and then iterate the movement steps and again evaluate
the restorative parameter(s). The dental professional and the
patient may repeat these iterative steps until the restorative
parameter(s) fall within desired ranges. Again, those of ordinary
skill in the art will appreciate that the iterative steps outlined
above may be performed in any order.
[0077] In step S26, the evaluation step may focus on the total
volume of tooth structure removed in order to reach the final
configuration. The evaluation may be based on, for example, a
desired threshold of the total volume of tooth structure. For
example, the dental professional may begin by superimposing the
dentition in the intermediate configuration and the dentition in
the final configuration to identify on the superimposed models the
intersection boundaries at the areas where the dentition of the
intermediate configuration protrudes beyond the dentition of the
final configuration. Using the three-dimensional geometrical
models, the volume of the protruding tooth structure may be
calculated. The volume of the protruding dentition represents the
volume of tooth structure that may be removed by the dental
professional during the prosthodontic procedure.
[0078] As a result of the evaluation and visualization, the dental
professional, perhaps after consulting the patient, may modify the
orthodontic treatment plan by moving and aligning the teeth using
virtual orthodontics into a configuration that varies from the
orthodontic treatment goal. The dental professional may also modify
the prosthodontic treatment plan by modifying the teeth using
virtual prosthodontics into a configuration that varies from the
restorative treatment goal. The dental professional may repeat
these steps several times. In addition, or in the alternative, as a
result of the evaluation and visualization, the dental professional
may modify the orthodontic treatment goal and/or the restorative
treatment goal. For example, the dental professional may modify the
restorative treatment goal by modifying the desired final tooth
position goal and/or tooth shape goal.
[0079] In step S26 the dental professional may superimpose the
modified models to determine the impact of the modifications on the
volume of tooth structure that extends outward from the
intersection boundaries. The dental professional may continue to
modify the virtual representations of the tooth structures in both
the virtual orthodontic plan and virtual restorative goal models
until the dental professional has iteratively arrived at an
acceptable preparation design that provides for a desired threshold
value of the parameters of interest. In the present invention, the
threshold value represents either a maximum, or if appropriate, a
minimum condition that the dental professional determines is an
acceptable variation to any given restorative parameter. For
example, the dental professional may set a threshold value that
represents the maximum amount of the total volume of the tooth
structure to be removed to create the final tooth configuration. A
threshold value may also be, for example, the maximum amount of
time available for treatment or the maximum thickness of a veneer
to be placed on a tooth.
[0080] The ability to virtually iterate the preparation
specifications as applied to the virtual beginning model of the
dentition as provided in steps S12 and S14 provides the dental
professional the ability to modify the preparation design prior to
any actual moving or cutting of the teeth. In addition, the dental
professional may also visualize the impact of the preparation to
the actual tooth, for example, in terms of volume of tooth material
removed, the different areas of tooth affected, and the depth of
the preparation, which is advantageous for avoiding sensitivity or
other treatments, such as root canals.
[0081] Once the dental professional has arrived at a preparation
design that meets desired thresholds for the restorative parameters
of interest, then the dental professional may set the intermediate
and final configurations, as shown at step S28. The dental
professional may then map out the orthodontic and prosthodontic
treatment plans based upon the beginning, intermediate and final
configurations, as shown at step S30.
[0082] Using the orthodontic and prosthodontic treatment plans, the
dental professional may next create, or have created, orthodontic
appliances and restorative preparations, as shown at step S32.
Steps S20, S22 and S24 may then proceed as shown in FIG. 11 and as
described above with respect to FIG. 9.
[0083] Many of the various embodiments included in the method steps
described with reference to FIGS. 9 and 11 are illustrated in the
following example.
[0084] In accordance with one embodiment of the present methods, a
dental professional may begin a restorative procedure, by first
meeting with a patient to determine which of the restorative
factors available are achievable to the degree desired by the
patient given the patient's treatment priorities. For example, the
patient may present to the dentist having a malocclusion like that
shown in FIG. 2. In this example, the patient may explain to the
dentist that she is anticipating a wedding day that is only six
months in the future. The bride-to-be wants her teeth (tooth X and
Y, in this example) to appear as white and as straight as possible,
but she is not concerned with the lingual surface of her teeth as
it does not bother her in its present condition. The dental
professional notes that the patient has relatively unhealthy teeth
and thus determines that the degree of tooth volume reduction, if
needed, should be minimized.
[0085] The dental professional may apprise the patient with her
options, while referring to the table in FIG. 1. Of the options
available, the dental professional mentions that Options B and C
provide the best desired outcome regarding time of treatment in
keeping with the patient's six-month timeframe. However, the dental
professional may explain that Option B is not as aesthetically
desirable as Option C, since Option B does not provide for a
matching veneer between the subject teeth. The dental professional
may also explain that Options B and C require a relatively thick
veneer be placed on one of the subject teeth to create the illusion
that the buccal surface of the teeth are properly aligned.
[0086] The patient reviews Options B and C and determines that
Options C provides a semi-satisfactory solution, but that the thick
veneer is problematic for her. The dental professional may then
suggest that the thickness of the veneer may be reduced by moving
the subject teeth first, as in Option D. The patient asks to
visualize the anticipated results.
[0087] To begin, the dental professional scans or photographs the
patient's actual dentition to create the virtual model and inputs
the data into a computer running the modeling software.
[0088] The dental professional may then manipulate the virtual
beginning model using the computer software, to simulate the effect
of orthodontic treatment by virtually repositioning the subject
teeth, tooth X and tooth Y, into a different position. In this
example, the dental professional determines that to expedite tooth
movement, the portion of tooth Y that overlaps tooth X is to be
removed.
[0089] Using the software model, the dental professional may
quantify a distance dj (FIG. 5) that may be achieved in the
prescribed timeframe (e.g. 6 months), which requires a certain
amount of tooth volume reduction Vi, and yields a veneer thickness
Tj. The dental professional may then manipulate the tooth X and
tooth Y again to generate a distance 62 that may be achieved in the
prescribed timeframe, which requires an amount of tooth volume
reduction V2 and yield a veneer thickness T2 and so on until the
dental professional decides that he has generated a number of
suitable options (d.sub.1 . . . n, V.sub.1 . . . n, T.sub.1 . . .
n) for the patient to review. Since the dental professional is
concerned with the amount of tooth volume reduction, the dental
professional may set a threshold value for the amount of tooth
volume reduction (V.sub.1, V.sub.2 . . . V.sub.n) that he has
determined is tolerable for this patient.
[0090] Next, the dental professional, in consultation with the
patient, may review the options and visualize the results, to
determine, which provides a reduction to the thickness of the
veneer to the patient's satisfaction. If the patient is satisfied,
and the dental professional and the patient have agreed upon the
desired final configuration for the dentition, the dental
professional may then use the computer software to create a
suitable prescription for moving the patient's teeth.
[0091] In the above example, before finalizing the prescription,
the patient informs the dental professional that her wedding plans
have been canceled, but that she still desires to have her teeth
restored within the next 12 months. The dental professional
explains that, since there is more time available for an
orthodontic procedure, the patient has more options to choose from
with regard to the restoration, for example, Options E, F, and G of
FIG. 1.
[0092] The dental professional then revisits the virtual model of
the patient's dentition and again begins to manipulate the teeth to
determine, as before, which Options now provide the patient with
the most suitable outcome given the new timeframe.
Preparation Guides
[0093] Although not shown in FIG. 11, the treatment plans could
also be used to create preparation guides or templates to help in
the restorative aspect of tooth preparation, temporary restoration
creation and creation of virtual wax-ups and possible final
veneers. An example of a preparation guide that could be created
using the treatment plans is discussed below with reference to
FIGS. 12-19.
[0094] FIG. 12 illustrates a tooth 20 in a beginning configuration,
prior to any prosthodontic modifications. In accordance with one
embodiment of the present methods, a dental professional may begin
a prosthodontic procedure by creating a first virtual model of a
patient's dentition in a beginning configuration, as shown at step
SI00 in FIG. 19. The virtual model may be generated by digitally
scanning and/or photographing the actual dentition and inputting
the data into a computer running modeling software. The dental
professional may store the beginning model for use in a comparison,
as described below.
[0095] The dental professional may then manipulate the virtual
beginning model using the computer software, as shown at step SI02.
This manipulation may include simulating the effect of orthodontic
treatment by virtually repositioning one or more teeth into a
different position, such that the amount of tooth reduction
necessary becomes reduced or more balanced for the desired
restorative outcome. On the computer screen, the dental
professional may also remove portions of the teeth and/or build-up
other portions of the teeth in order to generate a second virtual
model of the patient's dentition in a desired final configuration
(SI02). After consultation with the patient (SI04), the dental
professional may perform additional modifications to the second
virtual model (S106) until the dental professional and the patient
agree on the desired final configuration.
[0096] FIG. 13 illustrates one example of tooth modifications with
which the dental professional may experiment, and about which the
dental professional and the patient may confer. In FIG. 13, the
tooth 20 is shown in the beginning configuration (solid lines) and
in one possible final configuration (dashed lines). To reach the
final configuration the dental professional applies a dental
restoration to the tooth 20. In the illustrated embodiment, the
dental restoration is a veneer 22. However, those of ordinary skill
in the art will appreciate that the present methods may involve the
placement of any type of dental restoration, such as a bridge or a
crown. Before placing the veneer 22 on the tooth 20, the dental
professional prepares the tooth 20 by removing some surface
material. For example, the dental professional may need to
completely cut off a portion 24 (upper shaded portion) of the tooth
20 that would extend past the veneer 22. In other areas 26 (lower
shaded portions) the dental professional may need to remove just a
portion of the tooth surface (generally about 1 mm) in order to
create room for the veneer.
[0097] Once the dental professional and the patient have agreed
upon the desired final configuration for the dentition, the dental
professional may then use the computer software to superimpose the
first (beginning) and second (final) virtual models, as shown at
step SI08 in FIG. 19. For example, FIG. 14 illustrates a model of a
final configuration including the veneer 22 superimposed over a
model of the actual configuration of the tooth 20. In the
superimposed models, the portion 24 of the beginning dentition
protrudes beyond the veneer 22. The dental professional will remove
the protruding portion 24 from the patient's actual dentition
during the prosthodontic procedure.
[0098] To enhance the precision with which he or she removes
protruding portions of the patient's dentition, the dental
professional may use the superimposed models to generate a
preparation guide that emphasizes the protruding portions. The
preparation guide may be an overlay that substantially conforms to
the second dentition model, but includes apertures that enable
protruding portions of the actual dentition to extend beyond the
overlay so that they do not interfere with the proper seating of
the overlay upon the dentition.
[0099] To generate the overlay, the dental professional may begin
by identifying on the superimposed models the intersection
boundaries at the areas where the dentition of the first model
protrudes beyond the dentition of the second model, as shown at
step SI 10 in FIG. 19. For example, FIG. 14 illustrates one
intersection boundary 28 between the tooth 20 and the veneer 22.
The modeling software may be programmed to identify these
boundaries and to highlight them for the dental professional. The
portion 24 of the dentition that extends outward from the
intersection boundary 28 will be removed by the dental professional
during the prosthodontic procedure.
[0100] Once the intersection boundaries have been identified, a
preparation guide may be fabricated that substantially conforms to
the second model but includes apertures defined by the intersection
boundaries, as shown at step SI 12 in FIG. 19. An example of a
preparation guide or overlay 30, for a single tooth 20 is
illustrated in FIG. 15. The overlay 30 includes a wall portion 32
forming a cavity 34 configured to receive the tooth 20. The
preparation guide 30 includes an aperture 36 that corresponds to
the intersection boundary 28 shown in FIG. 14. The apertures 36
allow the protruding portions 24 of the tooth 20, to extend through
the aperture 36. The protruding portions 24 thus to not interfere
with proper seating of the guide 30 upon the tooth 20 in the
configuration prior to removal of any tooth material. Guide 30 may
be placed over tooth 20 to quickly and efficiently identify
protruding portions 24 that are to be removed.
[0101] After placing the preparation guide 30 over the tooth 20
(step SI 14 in FIG. 19), the dental professional removes the
protruding portion 24 (step SI 16). FIG. 16 illustrates the tooth
20 after removal of the protruding portion and with the preparation
guide 30 still in place. Using the guide 30 over the tooth 20 as
shown, the dental professional can remove the protruding portion of
the tooth 20 with greater precision as compared to a procedure
involving no overlay. The dental professional simply cuts or grinds
down any portions of the tooth 20 that extend beyond the overlay
30. The overlay 30 thus not only highlights the portions of the
tooth 20 to be removed, but it also shields portions of the tooth
20 that are not to be removed, thereby preventing unnecessary tooth
reduction.
[0102] If a dental restoration 22 is to be placed over the tooth
20, the dental professional also removes portions 26 of the tooth
20 in order to create space for the veneer 22, as shown in FIG. 16
and at step SI 18 in FIG. 19. The dental professional may use the
guide 30 to ensure that the removed tooth portions provide adequate
thickness for the veneer 22. For example, the dental professional
may place the guide 30 over the tooth 20 as shown in FIG. 16,
perforate the guide 30, and measure with a probe the distances
between the tooth 20 and the inner surfaces of the guide 30. When
the tooth 20 has been fully prepared, as shown in FIG. 17, the
dental professional applies the veneer 22, as shown in FIG. 18 and
at step SI20 in FIG. 19.
[0103] The guide 30 may be fabricated using any well known method
or suitable technique, for example, a rapid prototyping method or a
molding technique. During the fabrication process, the apertures 36
in the guide 30 may be produced as the guide 30 is formed, or they
may be cut out of the guide 30 after it has been formed.
[0104] A given guide may include just one aperture or a plurality
of apertures. The boundaries of the aperture(s) may be
electronically determined and the locations provided to cutting
machinery to remove material at the aperture locations.
Alternatively, the borders of the aperture(s) may be marked on the
guide during the fabrication process so the dental professional may
cut out the material at the aperture locations himself. The marking
may be performed using ink and/or laser marking, for example.
[0105] Those of ordinary skill in the art will appreciate that the
guide 30 described above may be used in conjunction with any of the
methods described above. For example, the guide 30 may be employed
during step S22 shown in FIGS. 8 and 10. Alternatively, the guide
30 may be used in other methods not disclosed herein. When used in
conjunction with a method including an orthodontic treatment plan
and a prosthodontic treatment plan, such as certain embodiments of
the methods described above, the dental professional may construct
the guide 30 by superimposing the virtual model of the patient's
dentition in the intermediate configuration with the virtual model
of the patient's dentition in the final configuration.
Alternatively, the dental professional may construct the guide 30
by superimposing the virtual model of the patient's dentition in
the beginning configuration with the virtual model of the patient's
dentition in the final configuration. Intersection boundaries of
the two superimposed virtual models would define the locations of
the apertures 36 in the guide 30.
Simulated Veneers
[0106] A simulated veneer may be generated automatically for all
orthodontic set-ups, including retrospective set-ups, such that a
library of models may be created systematically for the purpose of
diagnosis and screening for potential veneer cases. The automated
models may be measured in terms of, for example, volume, area and
thickness, to better characterize the impact of veneer placement to
the dentition prior, to initiating treatment. The simulated veneers
allow doctors to avoid unnecessary movement of the teeth and
removal of excessive amounts of tooth structure.
[0107] In one embodiment, orthodontic and prosthodontic procedures
may be combined virtually to create simulated veneers. Using an
orthodontic procedure, a starting and stopping point for a
veneering procedure may be determined. Thus, a virtual simulated
veneer may be created using a Final alignment position relative to
an Initial tooth position. Thus, the method described uses three
points of data: Initial position, simulated or actual Prepared
position (tooth material removed), Final alignment position (or any
other intermediate position).
[0108] The Initial and the Prepared positions are superimposed to
determine the difference in volume between the tooth in its Initial
position and the tooth in the Prepared position. The difference
represents the amount of tooth structure removed (or needed to be
removed). Thus:
V.sub.r=Vi-V.sub.p
where Vj is the initial tooth volume, V.sub.p is the prepared tooth
volume, and V.sub.r is the volume removed or preparation
volume.
[0109] The Initial position and the Final alignment position may
also be superimposed relative to a reference to define a sweep path
from the Initial position to the Final alignment position for each
tooth. The reference may be a static tooth, rugae, gingival and the
like. The sweep path defines a swept volume (V.sub.s), which
represents the union of the prepared tooth volume and restorative
structure volume (restoration volume) that is to be created. The
swept volume may need to be modified to assure that the swept
volume of the tooth does not intersect the swept volume of a
neighboring tooth or veneer.
[0110] The tool predicts the restoration volume (V.sub.res) as
follows:
V.sub.res=V.sub.s-Vp
where, the V.sub.p is subtracted from the V.sub.s in order to
create the total restoration volume, V.sub.res
[0111] The V.sub.res, V.sub.s, V.sub.P, V.sub.r may all be formed
as separate geometrical models apart from the tooth. Using features
of the tool, the V.sub.res (simulated veneer), for example, may be
manipulated through shape modification, as well as color
modification. The simulated veneer may also be printed as a
physical 3-D graphic or formed as a 3-D solid model.
[0112] Advantageously, the veneer-related quantification may be
used as the reference for a veneering review, evaluation and
analysis. The quantification may include, but is not limited to,
volume, thickness, area and the like. The quantified results may be
used to automatically or manually select the optimal start point
and stop point of a veneering treatment. In addition, the ability
to visualize the quantified results provides a reference for a
doctor or patient to select the preferable veneering option. For
example, as illustrated in the graph of FIG. 20, the doctor and
patient can determine the optimal start and stop point, which
yields the least amount of tooth mass removal and/or mass build-up
over a given amount of available treatment time. Optimality also
includes the probability of achieving the Final alignment position
for a given type of malocclusion in the available treatment time.
It should be understood that available treatment time equates to an
amount of tooth movement that may be realized during the available
treatment time.
[0113] FIG. 21 is a flowchart illustrating a process s2100 for
simulating the creation of veneers using orthodontic and
prosthodontic techniques. FIGS. 22A and 22B are simplified views of
a dental arch in an Initial position and in a Final alignment
position, respectively.
[0114] Referring to FIGS. 21, 22A and 22B, in step s2102, the
dental professional, perhaps in conjunction with a dental
laboratory, may create a computer-generated, 3-D, virtual model of
the patient's actual dentition in a beginning configuration 2202
(FIG. 22A). The virtual model may be generated prior to any tooth
preparation, so that the model represents the patient's dentition
in a pretreatment state. Some processes for making such a virtual
model are described in, for example, the '207 publication and the
'749 application previously incorporated herein by reference.
[0115] The dental professional as shown in step s2104, again
perhaps in conjunction with the dental laboratory or any other
company or service/product provider, may transform the virtual
model of the beginning configuration. The dental professional may
use virtual orthodontia to create a computer-generated, 3-D,
virtual model of the patient's dentition in a Final alignment
position or Final configuration 2204 (FIG. 22B), which represents
the desired "smile" or design goal that the patient and doctor
desire. The virtual orthodontia may include manipulation and
movement of teeth in the virtual model. The orthodontic treatment
may also include the modeling of several intermediate stages
between the beginning configuration and Final alignment position.
The beginning configuration or else one of the intermediate stages
may be considered an Initial position for starting the veneering
treatment as will be explained below.
[0116] In step s2108, a tentative restoration volume (simulated
veneer) may be calculated for a given time available for treatment.
FIG. 23 illustrates an embodiment for calculating the tentative
restoration volume of step s2108.
[0117] Referring now to FIG. 23, one embodiment of the present
methods may begin when a patient first consults a dental
professional regarding an orthodontic procedure and/or a
prosthodontic procedure (s2302). During the initial consultation,
the dental professional and the patient may discuss the patient's
treatment goal(s) and any constraints that might limit the time
available for treatment. For example, the patient may desire to
have his or her smile enhanced, but has only a six-month window of
opportunity for treatment. In this situation, the timeframe for
treatment is limited, and an appropriate orthodontic/prosthodontic
treatment plan must be set to fit within the timeframe.
[0118] In the present embodiment, the dental professional may
decide that substantially the entire six-month window of treatment
time be used to provide a particular amount of tooth movement
before starting the veneering treatment. Accordingly, in step
s2304, the dental professional, again perhaps in conjunction with
the dental laboratory or any other company or service/product
provider, simulates orthodontic movement of the teeth between the
beginning configuration and an Intermediate position.
[0119] In the present embodiment, the Intermediate position
represents the starting point or the Initial position for the
veneering treatment and is so specified (s2306). Now that the
dental professional knows the predicted Initial position of the
teeth, the dental professional may determine the Prepared
position.
[0120] In step s2308, the dental professional, again perhaps in
conjunction with the dental laboratory or any other company or
service/product provider, may transform the virtual model of the
Initial position using virtual prosthodontia to create a
computer-generated, 3-D, virtual model of the patient's dentition
in a Prepared or cut configuration. The virtual prosthodontics may
include the tooth mass removal that the dental professional deems
necessary to achieve the design goal (the desired "smile"). The
initial Prepared position is referred to hereinafter as the
tentative Prepared position.
[0121] In step s2308, the dental professional may quantify the
amount of tooth mass to be removed from the dentition to achieve
the desired smile. Referring to FIG. 24, in one embodiment,
Intermediate tooth 2402 and Prepared tooth 2404 are superimposed to
determine Prepared region 2406, which is the difference in volume
between Intermediate tooth 2402 and Prepared tooth 2404. Prepared
region 2406 represents the amount of tooth structure to be removed
(V.sub.r).
[0122] Referring again to FIG. 23, in step s2310, the dental
professional may superimpose the teeth in the Intermediate position
with the teeth in the Final alignment position to define a sweep
path from the Intermediate position to the Final alignment position
for each tooth to be veneered. For example, FIG. 25 is a side view
and top view of Prepared tooth 2404 where the swept volume V.sub.s
is shown. In this embodiment, swept volume V.sub.s is the space
occupied by moving a geometric model of Prepared tooth 2404 along a
path from the Intermediate position to the Final alignment
position.
[0123] Reference is made to the swept volume in the embodiments
described, however, one of ordinary skill in the art will
understand that many well-known numerical algorithms exist that may
be used to generate the envelope model of the Intermediate position
and the Final alignment position. For example, such algorithms are
referred to as the marching cube, convex hull, maxima, and Boolean
union operations. In addition, the swept volume may be estimated
analytically.
[0124] In step s2312, simulated veneers are generated as separate
geometric models apart from the Prepared tooth.
[0125] In step s2314, the simulated veneer may be evaluated by
reviewing the quantified measurements and visualizing the final
geometry of the simulated veneers. For example, Preparation region
2406 is calculated which represents the amount of tooth structure
to be removed in preparing the teeth. Also, the total restoration
volume is calculated by subtracting the Prepared tooth volume from
the sweep volume to create the total restoration volume. The
simulated veneers may be visualized to facilitate any shape
modification, color modification or any other modification that the
dental professional deems appropriate.
[0126] Referring again to FIG. 21, once a tentative restoration
volume has been calculated (s2108), a decision is made in step
s2110 as to whether the restoration volume is acceptable to the
dental professional and/or the patient. In some cases, for example,
the dental professional or patient may decide that the restoration
volume is too large or that the amount of tooth structure required
to be removed is too great. In these cases, the process may return
to the orthodontic simulation step s2104 where the dental
professional attempts to modify the design goal, which may include
manipulating the movement of the teeth to lessen the concerns of
the dental professional and patient.
[0127] In cases where the tentative restoration is acceptable, the
process continues to step s2112, where a check is made to determine
if the swept volume may need to be modified to assure that the
sweep volume of the tooth does not overlap the swept volume of a
neighboring tooth or veneer.
[0128] In step s2114, if overlap does exist, the overlap needs to
be resolved. One approach to remove the overlap is to deform or
locally modify the overlap area of the veneer model.
[0129] In step s2116, if there is no overlap, the tentative
restoration is deemed to be the final restoration and may be
subsequently made into an actual restoration.
[0130] Referring now to FIG. 26, as shown in step s2602, to create
an actual restoration from the final restoration, a veneer template
may be selected from a veneer library, which includes all types,
shapes and sizes of veneers. The veneer template provides a
reference geometry for the modeling of the actual restoration. The
reference geometry of the veneer template may be a 3D digital
model. Generally, the veneer template may be defined by various
physical parameters, such as height, width, thickness and the
like.
[0131] As shown in step s2604, after a veneer template has been
selected, the veneer template may be used to generate the actual
veneer shape model (actual restoration) by deforming the veneer
template to approximate the final restoration model. When the
physical parameters of the veneer template are changed, the
geometry of the actual restoration changes. The deformation may be
achieved through the adjustment of the physical parameters, 3D
morphing and the adjustment of the control points on the template
surface.
[0132] As shown in step s2606, after the actual veneer shape model
is generated, if necessary, the actual veneer shape model may be
further locally modified automatically or interactively to satisfy
any clinical requirements and user preferences.
[0133] Once the actual veneer shape model, with any modifications,
has been generated, it may be made into a physical veneer. In one
embodiment, the physical veneer may be created by creating the
reverse veneer with a template, filling the template with a dental
material, such as acrylic, composite, silicone, and the like, in
the uncured state and then curing the dental material, creating the
physical veneer in the desired shape. In one alternative
embodiment, the physical veneer may be built up directly in wax
with a 3-D printer. The wax may then be invested and cast into, for
example, porcelain or glass, using the lost-wax technique. In
another alternative embodiment, the physical veneer may be
converted directly into a CAD-CAM object that may be milled from a
block of porcelain or glass.
[0134] The following points may be considered aspects of the
present disclosure:
[0135] Point 1. A method for developing a dental treatment plan
comprising: (a) creating a virtual model of a dental patient's
dentition in a beginning configuration, the dentition including
teeth; (b) transforming the virtual model of the dentition using
virtual orthodontics from the beginning configuration into an
intermediate configuration; (c) transforming the virtual model of
the dentition using virtual prosthodontics from the intermediate
configuration into a final configuration, the final configuration
including the teeth and a dental restoration; (d) transforming the
dentition from the beginning configuration into the intermediate
configuration; (e) performing at least one of tooth surface
removal, tooth cutting and tooth reshaping on the dentition; and
(f) affixing the dental restoration to the dentition.
[0136] Point 2. The method of point 1, further comprising: g)
identifying and evaluating a restorative parameter.
[0137] Point 3. The method of point 2, further comprising iterating
steps b), c) and g).
[0138] Point 4. The method of point 2, wherein the restorative
parameter is a volume of tooth material to be removed, an aesthetic
feature, or a configuration of interior portions of the
dentition
[0139] Point 5. The method of point 2, further comprising: h)
determining whether the restorative parameter meets a desired
threshold.
[0140] Point 6. The method of point 5, further comprising creating
an orthodontic plan based upon the beginning configuration, the
intermediate configuration and the final configuration.
[0141] Point 7. The method of point 6, further comprising creating
an orthodontic appliance based upon the orthodontic plan.
[0142] Point 8. The method of point 1, further comprising creating
a restorative goal based upon the beginning configuration, the
intermediate configuration and the final configuration.
[0143] Point 9. The method of point 8, further comprising creating
a prosthodontic preparation based upon the restorative plan.
[0144] Point 10. The method of point 1, wherein transforming the
actual dentition from the beginning configuration into the
intermediate configuration comprises the use of at least one dental
aligner.
[0145] Point 11. The method of point 1, further comprising
verifying the efficacy of the at least one of tooth surface
removal, tooth cutting and tooth reshaping.
[0146] Point 12. The method of point 11, wherein verifying
comprises positioning a preparation guide over the dentition and
measuring a clearance between a tooth and the preparation
guide.
[0147] Point 13. The method of point 12, wherein the preparation
guide is substantially congruent to the final configuration of the
dentition.
[0148] Point 14. The method of point 12, wherein the preparation
guide includes at least one aperture that enables a portion of the
tooth to protrude beyond a wall portion of the preparation
guide.
[0149] Point 15. The method of point 11, wherein verifying
comprises positioning the dental restoration on the dentition and
verifying a proper fit.
[0150] Point 16. The method of point 15, further comprising
repeating step e) when the dental restoration does not fit properly
on the dentition.
[0151] Point 17. A method for preparing a dental treatment plan
comprising: creating a virtual model of a dental patient's
dentition, the dentition including teeth; transforming the virtual
model of the dentition using virtual prosthodontics to yield a
desired outcome relative to at least one restorative parameter;
iterating on the transforming step until substantially achieving
the desired outcome relative to the at least one restorative
parameter; and generating a prosthodontic treatment plan based upon
the substantially achieved treatment goal.
[0152] Point 18. The method of point 17, wherein the at least one
restorative parameter comprises a volume of tooth material to be
removed, an aesthetic feature, a configuration of interior portions
of the dentition, or a combination thereof.
[0153] Point 19. The method of point 17, wherein iterating on the
transforming step comprises: transforming the virtual model of the
dentition using virtual orthodontics to facilitate substantially
achieving the desired outcome relative to the at least one
restorative parameter.
[0154] Point 20. A preparation guide for use during a prosthodontic
procedure, comprising: a virtually generated overlay configured to
cover at least a portion of teeth in a patient's upper or lower
arch, the overlay including a wall portion forming at least one
cavity configured to receive the teeth; wherein the wall portion
includes at least one aperture configured to receive a protruding
portion of the teeth.
[0155] Point 21. The preparation guide of point 20, wherein the
virtual overlay is configured to cover all teeth in a patient's
upper or lower arch.
[0156] Point 22. A method of fabricating a preparation guide for
use during a prosthodontic procedure comprising: creating a first
virtual model of a patient's dentition in a beginning
configuration; manipulating the virtual model using computer
software to create a second virtual model of the patient's
dentition in a desired final configuration; superimposing the first
and second virtual models; identifying, in the superimposed models,
intersection boundaries at areas where the dentition of the first
model protrudes beyond the dentition of the second model; and
fabricating the preparation guide to substantially conform to the
second model and having apertures defined by the intersection
boundaries.
[0157] Point 23. The method of point 22, further comprising the
step of reviewing the second virtual model with the patient.
[0158] Point 24. The method of point 23, further comprising the
step of manipulating the second virtual model to arrive at an
alternate desired final configuration.
[0159] Point 25. A method for developing a dental treatment plan,
the method comprising: (a) creating a virtual model of a dental
patient's dentition in a beginning configuration, the dentition
including teeth; (b) identifying at least one parameter of the
dental treatment program to be controlled so that the parameter
falls within a desired range; (c) transforming the virtual model of
the dentition using at least one of virtual orthodontics and
virtual prosthodontics from the beginning configuration into a
final configuration; (d) evaluating the effect of the transforming
step on the parameter; and (f) repeating steps b), c) and d) until
the transforming step produces a desired effect on the
parameter.
[0160] Point 26. The method of point 25, wherein identifying at
least one parameter of the dental treatment program to be
controlled so that the parameter falls within a desired range
comprises identifying a plurality of parameters of the dental
treatment program to be controlled so that the plurality of
parameters fall within desired ranges.
[0161] Point 27. A method for generating dental information of a
patient comprising: creating a virtual model of a patient's
dentition in a first configuration, the dentition including at
least one tooth having a reference volume; generating a model
volume created as the at least one tooth travels from the first
configuration to a second configuration; and subtracting the
reference volume from the model volume to yield a build-up
volume.
[0162] Point 28. The method of point 27, further comprising
creating a virtual model of a patient's dentition in a prepared
configuration.
[0163] Point 29. The method of point 28, further comprising
determining a removed volume by subtracting a volume of the
dentition in the prepared configuration from the reference
volume.
[0164] Point 30. The method of point 29, further comprising
determining a restoration volume by combining the removed volume
and the build-up volume.
[0165] Point 31. The method of point 28, further comprising:
transforming the virtual model of the patient's dentition from the
first configuration into a first intermediate configuration;
generating a first intermediate model volume created as the at
least one tooth travels from the first intermediate configuration
to the second configuration; subtracting the reference volume from
the first intermediate model volume to yield a first intermediate
build-up volume; and evaluating the effect of the transforming step
on the first intermediate build-up volume to determine if the
effect is a desired effect.
[0166] Point 32. The method of point 31, further comprising:
determining a removed volume by subtracting a volume of the
dentition in the prepared configuration from the reference volume;
and determining a restoration volume by combining the removed
volume and the first intermediate build-up volume.
[0167] Point 33. The method of point 31, further comprising:
transforming the virtual model of the patient's dentition from the
first configuration into a second intermediate configuration;
generating a second intermediate model volume created as the at
least one tooth travels from the second intermediate configuration
to the second configuration; subtracting the reference volume from
the second intermediate model volume to yield a second intermediate
build-up volume; and evaluating the effect of the transforming step
on the second intermediate build-up volume to determine if the
effect is a desired effect.
[0168] Point 34. The method of point 33, further comprising:
determining a removed volume by subtracting a volume of the
dentition in the prepared configuration from the reference volume;
and determining a restoration volume by combining the removed
volume and the second intermediate build-up volume.
[0169] Point 35. The method of point 27, wherein generating the
model volume comprises: determining the volume of the virtual space
occupied by the at least one tooth as the at least one tooth
travels from the first configuration to the second
configuration.
[0170] Point 36. The method of point 27, further comprising:
verifying whether the build-up volume overlaps a neighboring
virtual tooth volume or virtual veneer volume.
[0171] Point 37. The method of point 36, further comprising:
deforming the build-up volume to resolve the overlap.
[0172] Point 38. The method of point 27, wherein creating the
virtual model of a patient's dentition comprises generating a
reference contour mesh crown representing the surface boundary of
the at least one tooth.
[0173] Point 39. The method of point 38, wherein generating the
model volume comprises: calculating the virtual space occupied by
the reference contour mesh crown as the reference contour mesh
crown travels from the first configuration to the second
configuration.
[0174] Point 40. A system for generating dental information of a
patient comprising a processor configured to: create a virtual
model of a patient's dentition in a first configuration, the
dentition including at least one tooth having a reference volume;
generate a model volume created as the at least one tooth travels
from the first configuration to a second configuration; and
subtract the reference volume from the model volume to yield a
build-up volume.
[0175] Point 41. The system of point 40, wherein the processor is
further configured to create a virtual model of a patient's
dentition in a prepared configuration.
[0176] Point 42. The system of point 41, wherein the processor is
further configured to determine a removed volume by subtracting a
volume of the dentition in the prepared configuration from the
reference volume.
[0177] Point 43. The system of point 42, wherein the processor is
further configured to determine a restoration volume by adding the
removed volume and the build-up volume.
[0178] Point 44. The system of point 40, wherein the processor is
further configured to: transform the virtual model of the patient's
dentition from the first configuration into a first intermediate
configuration; generate a first intermediate model volume created
as the at least one tooth travels from the first intermediate
configuration to the second configuration; subtract the reference
volume from the first intermediate model volume to yield a first
intermediate build-up volume; and evaluate the effect of the
transform step on the first intermediate buildup volume to
determine if the effect is a desired effect.
[0179] Point 45. The system of point 44, wherein the processor is
further configured to: transform the virtual model of the patient's
dentition from the first configuration into a second intermediate
configuration; generate a second intermediate model volume created
as the at least one tooth travels from the second intermediate
configuration to the second configuration; subtract the reference
volume from the second intermediate model volume to yield a second
intermediate build-up volume; and evaluate the effect of the
transform step on the second intermediate build-up volume to
determine if the effect is a desired effect.
[0180] Point 46. The system of point 40, wherein the processor is
further configured to: verify whether the build-up volume overlaps
a neighboring virtual tooth volume or virtual veneer volume.
[0181] Point 47. The system of point 46, wherein the processor is
further configured to: deform the build-up volume to resolve the
overlap.
[0182] Point 48. The system of point 40, further comprising a
mechanism for displaying a virtual representation of the first
configuration, the build-up volume, the restoration volume, the
removed volume, the second configuration, the final configuration,
the prepared configuration or the reference volume.
[0183] The flowcharts provided herein illustrate example
embodiments of the present methods. In some alternative
embodiments, the steps shown in one or more figures may occur out
of the order presented. For example, in some cases, two steps shown
in succession may be executed substantially concurrently, or the
steps may sometimes be executed in the reverse order. Those of
ordinary skill in the art will also appreciate that the scope of
the present methods is defined only by the claims provided below,
and therefore some embodiments may not include all of the steps
shown in the figures.
[0184] The above description presents the best mode contemplated
for carrying out the present prosthodontic and orthodontic
apparatus and methods, and of the manner and process of making and
using them, in such full, clear, concise, and exact terms as to
enable any person skilled in the art to which it pertains to make
these apparatus and use these methods. These apparatus and methods
are, however, susceptible to modifications and alternate
constructions from those discussed above that are equivalent.
Consequently, these apparatus and methods are not limited to the
particular embodiments disclosed. On the contrary, these apparatus
and methods cover all modifications and alternate constructions
coming within the spirit and scope of the apparatus and methods as
generally expressed by the following claims, which particularly
point out and distinctly claim the subject matter of the apparatus
and methods.
* * * * *