Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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TWO-PHASE INVISIBLE ORTHODONTICS
Technical Field
[0001] The present invention is related to an improved method to correct
orthodontic malocclusions. It includes a first phase employing traditional
molar
orthodontic appliances such as bands, wires and the like. A second phase
employs a
plastic tray which exerts orthodontic correcting forces to treat the
malocclusion.
Background of the Invention
[0002] Orthodontics relates to creating space and moving the teeth within that
space
traditionally with appliances, wires, and some form of ligation. The lay word
used is
braces. This is a highly labor intensive system requiring frequent
reactivations by the
orthodontist to adjust the wires. These braces are mounted to the teeth using
an
adhesive/acid system that is uncomfortable for some adult patients and time
consuming for the practitioner. It is also expensive.
[0003] Align Technology introduced treating patients, mainly adults, with a
computer designed series of plastic trays. These trays take the original
impression of
the patient's teeth and use a digital database to create an actual mold of the
teeth and
then advance that mold's information to create a series of trays that attempt
to treat
the patient's malocclusion without braces. This has proven very expensive and
time
consuming, as it requires the long lead times to start treatment and it takes
the plastic
trays a long period of time to affect tooth movement. Busy adults have to be
patient
and carefully follow the regimen and the orthodontist/manufacturer many times
has to
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recreate the series of trays as they need a mid-course correction due to
either non-
compliance or errors in the computer assumptions. Align, the original inventor
of
digital aligners, actually patented mid-course corrections and insurance when
treatment is started. While the patient has virtually invisible treatment, it
may take
years to complete and generally involves a big compromise when compared to
traditional treatment.
[0004] It is estimated that there are millions of patients that want their
anterior teeth
corrected, refuse braces, and can't afford the above system. Some of them turn
to
dental laminates to cosmetically cover the problem but these also are
expensive and
need to be replaced periodically. It is then important that a system be
designed that is
less costly as the InvisAlign System, does not entail fixing visible braces to
the teeth,
but that can correct the visible teeth that may be misaligned using a nearly
invisible
plastic tray system to satisfy the needs of the above patients. InvisAlign is
also very
restricted on the types of patients that can be treated using their designs.
[0005] Tooth positioners made of clear plastic were developed over 50 years
ago to
guide teeth near their treatment goal after fixed therapy. Digital imaging in
orthodontics was presented early in, for example, U.S. Patent No. 5,605,459.
Ormco
describes manipulating digital images of teeth for creating braces in U.S.
Patent No.
5,533,895 and other previous patents.
[0006] Laser scanning to produce a 3-D model of the teeth in U.S. Patent Nos.
5,338,198 and 5,452,219. Digital manipulation is described in U.S. Patent Nos.
5,607,305 and 5,587,912.
[0007] In phase one, an appliance such as the Pendex as shown in Figure 1 can
be
used to expand the maxillary arch width while maintaining the anteriors with a
clear
passive tray. The expansion as shown above allows great space to be gained so
that
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less enamel reduction and easier repositioning of the anterior teeth to the
prescribed
ideal finish may be more easily and predictably maintained.
[0008] The quad helix has been proven for decades to be useful to expand
unnaturally narrow arches, especially younger females. After phase one with
the quad
helix, the digital model and the case will have most obstructions removed for
path
analysis and the quad helix is virtually impossible to see.
[0009] Palatal arch bars and their sheathes are very simple devices to
rotation and
distallize molars creating large amounts of space to allow the pre-molars to
freely
drift posteriorly while holding the anteriors in a passive clear tray during
Phase I.
[0010] Lingual arches, used on the mandibular behind the teeth, are connected
to
the molar band and used to upright the anterior teeth while placing gentle
pressure to
promote dental alveolar lateral growth. Here no lower plastic tray is used
until Phase
II and again there will be greater space to use while making the digital
prescriptive
trays for Phase II.
Brief Summaly of the Invention
[0011] There is provided according to the invention a two-phase method of
orthodontically correcting maloccluded teeth that includes: A first phase
aesthetic
treatment regimen that begins with traditional molar orthodontic appliances
and
therapy to rotate, align, intrude and/or level the molar area. Path analysis
via a
CAD/CAM to see if stripping is needed and where it is best applied based on
tooth
width and arch width. A clear retaining tray is made to control the balance of
teeth
during Phase One. After the Phase I correction, taking a new impression with
the
molar correction and stripping in place and a bite registration and then
digitally or
realistically resetting the teeth to the ideal occlusion and creating a series
of plastic
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trays that will complete the corrections from the Phase I position to the
final ideal
position when a retaining tray will be used to hold the position.
[0012] This invention concerns an improved method of aesthetically
treating
more patients using a two-phase treatment plan. It starts with an impression
or digital
scan of the patient's teeth and bite registration being sent digitally to a 3-
D modeler
such as OrthoCAD where a digital model of the teeth and their relationship are
established. Millimeters of crowding are determined and the type of
malocclusion
analyzed to chart the following process. Bands or acrylic plates as indicated
are
applied to the posterior molars and mechanics used to derotate, intrude,
torque,
expand, and/or upright the molars, creating the space for at least one tooth's
worth of
space in each arch. This will allow better treatment with the plastic
activators on the
anteriors without fixed appliance therapy and anchorage for better retention
after
treatment.
[0012a] According to one aspect of the present invention, there is
provided a
two-phase method for orthodontically correcting malposed teeth, comprising: a.
in
Phase I, conducting a path analysis via a CAD/CAM to determine if stripping is
required based on tooth width and arch width before an aesthetic treatment
regimen
to rotate, align, intrude or level a molar area with molar orthodontic
appliances;
b. constructing a clear retaining tray to control a balance of the teeth
during the
aesthetic treatment regimen; c. after correction in Phase I, creating a new
impression
with correction of the molar area, optionally with stripping in place; d.
optionally
performing a bite registration; e. digitally or realistically resetting the
teeth to a final
ideal position in Phase II; f. constructing a series of plastic trays to
complete
correction to the final ideal position in Phase II; and g. after correction in
Phase II,
constructing a final tray for all the teeth to finalize correction and begin
retention of
the teeth.
[0012b] According to another aspect, the present invention relates to
a method
of constructing an orthodontic system for correcting malposed teeth, the
method
comprising: a. in Phase I, conducting a path analysis via a CAD/CAM to
determine if
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stripping is required based on tooth width and arch width before an aesthetic
treatment regimen to rotate, align, intrude or level a molar area with molar
orthodontic
appliances; b. constructing a clear retaining tray to control a balance of the
teeth
during the aesthetic treatment regimen; c. digitally resetting the teeth to a
final ideal
position in Phase II based on a new impression, obtained after correction in
Phase I,
with correction of the molar area and optionally with stripping in place, and
an
optional bite registration obtained thereafter; d. constructing a series of
plastic trays
to complete correction to the final ideal position in Phase II; and e. after
correction in
Phase II, constructing a final tray for all the teeth to finalize correction
and begin
retention of the teeth.
Brief Description of the Drawings
[0013] Figure 1 is a perspective view of one embodiment of a
traditional molar
orthodontic appliance useful in the practice of the present invention.
[0014] Figure 2 is a perspective view of another embodiment of a
traditional
molar orthodontic appliance useful in the practice of the present invention.
[0015] Figure 3 is a perspective view of another embodiment of a
traditional
molar orthodontic appliance useful in the practice of the present invention.
[0016] Figure 4 is a perspective view of another embodiment of a
traditional
molar orthodontic appliance useful in the practice of the present invention.
[0017] Figure 5 is a perspective view of a tray useful as a retainer or as
one of
a series of aligner trays used in the practice of the present invention.
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[0016] Figure 4 is a perspective view of another embodiment of a
traditional
molar orthodontic appliance useful in the practice of the present invention.
[0017] Figure 5 is a perspective view of a tray useful as a retainer or
as one of
a series of aligner trays used in the practice of the present invention.
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Detailed Description of the Invention
[0018] Since it is virtually impossible to see molars at the back of the
mouth, more
traditional appliances can be used to manipulate the molars gaining more space
for the
anterior teeth. Professionals may use lip bumpers, Crozats, palatal bars,
Herbst,
Distal Jets, expansion screws, Molar Movers, and other molar management
appliances
known to practitioners as are variously shown in Figures 1-4. This will
generally
recover, just through rotations and uprighting, the space for at least one
anterior tooth
in each arch. This will generate adequate space in the anteriors for
correction and
provide good anchorage for anterior movement. Further space, if needed, can be
gained by judiciously stripping of teeth no more than .5mm per side. The goal
is to
clear a path for the teeth to straighten without impediment. It is estimated
that Phase I
will last 2-6 months. Records will be kept of the individual tooth and arch
width
measurements before the stripping and after. Again, digital 3-D simulation can
perform path analysis and the ideal amount of space needed and where it can be
gained. Between stripping of anteriors and rotation of molars, it's possible
that
extraction of teeth on marginal cases can be avoided.
[0019] After setting up anchorage with the molars and stripping the teeth as
needed,
a new impression or digital scan and bite registration is sent to the digital
computer
aided design company and a treatment analysis is performed after the Phase I
treatment of molar correction, anchorage and stripping.
[0020] A new scan or impression of the teeth now and analysis for the new,
improved status of the anteriors. There has been much literature and clinical
results
of correcting the molar rotations and then holding them without any aesthetic
affect.
Cetlin, Gianelly, et al have written about these low compliance appliances
with great
affect. Computer analysis when it seems that maximum progress has been
achieved
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with the molars and that any anterior-posterior correction has been achieved
through
the control of a removable plate on the anteriors, as dictated by Margolis and
Cetlin
during the last century. It has been described by others as "drift-odontics"
as you
open up space anterior to the molars and then wait for the middle teeth, or
bicuspids,
to drift to their final placement. This eliminates much discomfort of trying
to
mechanically correct the bicuspids, although the activator (active plastic
tray) can be
used for extreme cases. While the RPE, SPE, Pendulum, Burstone, et al
appliances
can replace the palatal arch bar system on the upper molars and a lip bumper
on the
lowers, it is intended that the inexpensive PAB/bumper system common to the
profession be the preferred embodiment.
[0021] A final tray such as tray (10) in Figure 5 is formed for all the teeth
after the
bands have been removed and placed to finalize correction and begin retention.
[0022] Generally, this process is to address the millions of adults that are
at or near
Class I or Class II Division I molar relationships and have crowded anteriors.
Also,
many patients that already completed orthodontic treatment in their youth and
simply
need to correct unattractive rotations could benefit from this system.
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