Note: Descriptions are shown in the official language in which they were submitted.
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TONGUE THRUST ORAL HABIT RETRAINER
The present invention relates to an oral corrective device for
correcting tongue thrust problems associated with swallowing and other
oral habits.
In normal swallowing, the tip of the tongue is first placed against
the front of the palate or upper jaw just behind the front teeth. In
swallowing, the tongue and its top surface is then moved upwards and
backwards against the hard palate. People with tongue thrust problems
(usually children) generally position the tongue too low in the mouth and
too far forward at the start of a swallow which moves the tongue
forward against, and in front of, the front upper teeth at the end of the
swallow. The repeated pressure of the tongue thrust habit often
displaces the upper front teeth and surrounding bone upwards and
forwards, creating an open space between the upper and lower front
teeth. This open space is called an anterior bite malocclusion. Most
often, tongue thrusting patients also press their lower lips against the
back of the upper front teeth during an incorrect and slow swallow,
further aggravating the malocclusion.
The applicant has previously described a device for correcting
tongue thrust problems in U.S. Patent No. 4,997,182. The applicant has
found this device to be effective to correct tongue thrust problems and
facilitate the correction of malocclusions caused by incorrect swallowing
and other oral habits. The device is believed to operate through
stereotaxic conditioning, where the densely innervated surface of the
tongue tip is trained to contact the densely innervated anterior bend of
the hard palate located immediately behind the upper front teeth. This
trained position is the correct position for initiating a normal swallow.
The device of U.S. Patent No. 4,997,182 needs improvement however,
since it requires substantial skill and patience to correctly fit the device in
a patient's mouth. Accordingly, features have been added to the basic
tongue thrust corrective device of U.S. Patent No. 4,997,182 to facilitate
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fitting the device to a patient's mouth. The entire disclosure of U.S.
Patent No. 4,997,182 is incorporated herein by reference.
SUMMARY OF THE INVENTION
The invention provides a first embodiment tongue thrust oral
corrective device designed to be fitted to the upper posterior teeth and to
train the user to correctly swallow without thrusting the tongue against
the front teeth, the device comprising:
a teeth-fitting segment comprising (1 ) a first occlusal trough
adapted to fit under at least one, on one side of the user's mouth,
of the posterior teeth, ~2) a second occlusal trough adapted to fit
under at least one, on the other side of the user's mouth, of the
posterior teeth, and (3) a forward portion adapted to fit under at
least two upper front teeth;
a downward projection extending from the teeth-fitting
segment and adapted to create a ramp for directing the tip of the
user's tongue towards the soft tissue of the front anterior bend of
the user's palate; and
a palatal bridge having a loop shape that loops above the
teeth-fitting segment and connects the first and second occlusal
troughs, wherein the palatal bridge is adapted, in conjunction with
the teeth-fitting segment and the downward projection, to create
an opening allowing the user's tongue to contact the soft tissue of
the front anterior bend of the user's palate.
The combination of the downward projection, the teeth-fitting segment
and the palatal bridge form a rearwardly opening pouch or channel in
which the tongue is engulfed. This embodiment allows the device to be
stably positioned in the patient's mouth while the device is being fitted
by creating a three point contact with the upper posterior teeth, on each
side of the mouth, and the upper front teeth. After the device is tightly
fitted to a patient's upper posterior teeth, the portion of the device that
allows contact with the upper incisal teeth is preferably cut or ground
away before regular use of the device so that it does not interfere with
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the desirable downward and rearward drifting of the upper front teeth
that occurs when they are relieved of repeated tongue thrust and lower
lip pressure.
Preferably, the palatal bridge is adapted to avoid contacting the
palate. Preferably, the downward projection is adapted to avoid applying
pressure to the lower teeth or jaw when a patient closes his or her
mouth. Preferably, each occlusal trough has a hole for anchoring a
polymerizable material. Preferably, the holes have bevelled edges suitable
for engaging the polymerizable material to facilitate bonding between the
device and the polymerizable material. Preferably, the palatal bridge is
adapted so that the top of the loop sits at a distance of from about 2 mm
to about 4 mm from the palate. Preferably, the tongue thrust corrective
device further comprises one or more lateral molding elevations from the
teeth-fitting segment adapted to be fit in the patient's mouth in front of
(i.e., to the cheek side of) at least about one of the posterior teeth.
Preferably, the lateral molding elevations are adapted to avoid interfering
with side access to the patient's upper six-year molars. Preferably, the
tongue thrust corrective device further comprises at least one alignment
projection adapted to be seated in front of the front teeth and a marker
on the alignment projection at the median line of the device for aligning
the device with either (1) the gap between the two front teeth, or (2) the
center line of a patient's face.
The invention further provides a second embodiment tongue thrust
oral corrective device designed to be fitted to the upper posterior teeth
and to train the user to swallow without thrusting the tongue against the
front teeth, the device comprising:
a teeth-fitting segment comprising (1 ) a first occlusal trough
adapted to fit under at least one, on one side of the user's mouth,
of the posterior teeth, and (2) a second occlusal trough adapted to
fit under at least one, on the other side of the user's mouth, of the
posterior teeth;
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a downward projection extending from the teeth-fitting
segment and adapted to create a ramp for directing the tip of the
user's tongue towards the soft tissue of the front anterior bend of
the user's palate;
a palatal bridge having a loop shape looping above the teeth-
fitting segment and connecting the first and second occlusal
troughs, wherein the palatal bridge is adapted, in conjunction with
the teeth-fitting segment and the downward projection, to create
an opening allowing the user's tongue to contact the soft tissue of
the front anterior bend of the user's palate; and
one or more lateral molding elevations extending from the
teeth-fitting segment adapted to fit in the patient's mouth to the
outer or inner side of at least about one of the posterior teeth.
The corrective device of the invention is fitted to a patient's mouth by
molding a polymerizable material onto the device and around the patient's
posterior teeth and subsequently curing the material into a resilient solid
that conforms to the shape of these teeth. To effectively seat the device
around the patient's teeth, the shaped, cured material must conform to
the shape of the outside surfaces of the patient's teeth and that shaped
polymeric material must be strongly bonded to the device. The lateral
molding elevations of the present invention allow the polymerizable
material to be easily conformed to the shape of the outside surfaces of
the fitted teeth. Since the lateral molding elevations are preformed when
the device is manufactured, they provide a sturdy retaining wall for
forming the moldings of the outer surfaces of the patient's teeth. The
lateral molding elevations also provide important support and containment
for the polymerizable material after it has been molded to the patient's
teeth but before it has been cured. The preferred embodiments of the
first embodiment apply to the second.
The invention further provides a third embodiment tongue thrust
oral corrective device designed to be fitted to the upper posterior teeth
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and to train the user to swallow without thrusting the tongue against the
front teeth, the device comprising:
a teeth-fitting segment comprising (1) a first occlusal trough
adapted to fit under at least one, on one side of the user's mouth,
of the posterior teeth, and (2) a second occlusal trough adapted to
fit under at least one, on the other side of the user's mouth, of the
posterior teeth, wherein each occlusal trough has a hole for
anchoring a polymerizable material;
a downward projection extending from the teeth-fitting
segment and adapted to create a ramp for directing the tip of the
user's tongue towards the soft tissue of the front anterior bend of
the user's palate; and
a palatal bridge having a loop shape looping above the teeth-
fitting segment and connecting the first and second occlusal
troughs, wherein the palatal bridge is adapted, in conjunction with
the teeth-fitting segment and the downward projection, to create
an opening allowing the user's tongue to contact the soft tissue of
the front anterior bend of the user's palate.
The holes of this embodiment facilitate bonding between the pre-formed
device and the polymerizable material that is used to fit the device to a
patient's mouth. Preferably, the holes have angled or bevelled edges to
allow portions of the polymerizable material having greater diameter than
the hole to be molded on both sides of the hole. These large diameter
portions act as plugs or undercuts that stabilize the polymerizable
material from separating from the pre-formed device. The preferred
embodiments of the first embodiment apply to the third.
The invention further provides a method of fitting a tongue thrust
corrective device comprising the steps of:
fitting the polymerizable material to the upper surface of the
first and second occlusal troughs;
molding the polymerizable material to the shape of the upper
teeth of a patient while visually aligning the centerline of the
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device with the centerline of the patient's teeth or mouth and
assuring a stable three-point contact between teeth-fitting segment
of the device and the upper front teeth and the posterior teeth on
both sides of the mouth;
removing the device from the molded teeth; and
curing the polymerizable material to increase its strength.
Preferably, the method further comprises an initial partial curing following
the fitting step and before the removing step. Preferably, the
polymerizable material is a light-curable material and the curing comprises
light curing. Preferably, the method further comprises sculpting the cured
device to remove any portion of the device that contacts the upper front
four teeth, with the sculpted device adapted to allow movement and
eruption of the front teeth and adjustment to the local bone to correct
open bite malocclusions caused by tongue thrust disorders.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 displays an embodiment of the device
Figure 2 displays a bottom view of an embodiment of the
corrective device.
Figure 3 displays a side view of an embodiment of the corrective
device.
Figure 4 displays a cutaway along the central axis of symmetry of
the displayed device.
Figure 5 displays the cutaway of Figure 4 as it would seat in a
patient's mouth during the fitting process.
DEFINITIONS
The following terms shall have the meaning set forth below:
~ occlusal surface of upper posler;or (or buccal) teeth of the patient
The occlusal surface of upper posterior (or buccal) teeth of the
patient is the chewing surface of the upper teeth located behind the
canines.
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~ molding walls or elevations
An exterior molding wall or elevation is an elevation on one side of a
trough designed to contain and support the polymerizable material to
be molded to the shape of some of a patient's upper teeth. The
elevations support and facilitate shaping the polymerizable material
to conform to the outer surfaces of the upper arch and teeth.
~ occlusal trough
An occlusal trough is a piece designed to facilitate molding an device
of the invention to the occlusal and side surfaces of the molars.
~ ~,oly".e.i~able .~.aterial
A polymerizable material is any material that can be molded to
conform to the shape of one or more teeth and subsequently cured
to lock it into the molded shape.
~ pGsler;or teeth
The posterior teeth are the teeth behind the canines; these teeth are
sometimes called the buccal or cheek teeth.
DETAILED DESCRIPTION
In Figure 1, teeth-fitting segment 1 of device 20 is
approximately semi-circular in shape and has a forward portion 2 and two
rearward portions termed first occlusal trough 3 and second occlusal
trough 4. Forward portion 2 is divided by reference line 5; that part of
portion 2 in front of line 5, portion 2', will be cut or ground away after
device 20 is fitted to the patient. Teeth-fitting segment 1 is sized to
contact the upper posterior teeth at first occlusal trough 3 and second
occlusal trough 4. Preferably, teeth-fitting segment 1 contacts at least
one of the two upper posterior teeth on each side that are located
immediately behind the canine tooth (i.e., the first and second molars).
For children of less than about ten years of age, the teeth-fitting segment
1 will generally contact second baby molars; for older children and adults,
30 teeth-fitting segment 1 will generally contact permanent bicuspids, i.e.,
premolars. Palatal bridge 6 forming the top of the tongue channel 11
(see Figure 4) has a loop shape (channel visible in Figures 4 and 5). The
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top of palatal bridge 6 preferably seats about 2 mm to about 4 mm from
the palate. First lateral molding elevation 7 and second lateral molding
elevation 7' are adapted to seat beside the baby (i.e., deciduous) molars
or permanent bicuspids of the user. Handle 14 can be used to aide the
5 process of fitting and centering the device to a patient. As illustrated in
Figures 1 and 2, most embodiments of the device will have two
symmetrical halves. In Figure 1, the device is symmetrical about the
axis line indicating the cut-away view of Figure 4.
Figure 2 displays a bottom view of an embodiment of
10 the corrective device in which first hole 9 and second hole 9', which
facilitate bonding of polymerizable material with the device, are visible.
Downward projection 8 is visible in Figure 2 and in Figure 3, which
shows a side view. Downward projection 8 forms the lower part of a
channel or pouch in which the tongue fits. The channel 11 is shaped to
15 direct the tip of the tongue to stretch upwards towards and contact the
soft tissue of the front anterior bend of the user's palate
Figure 4 displays a cutaway along the central axis of
symmetry of the displayed device, and in this view channel 11, which is
formed from palatal bridge 6 and downward projection 8, and which
20 directs the positioning of the user's tongue (30), is visible.
Figure 5 displays the cutaway of Figure 4 as it would
seat in a patient's mouth. Teeth 31, gums 32, lips 33 and palate 34 are
also illustrated. The palatal bridge 6 defines a tongue hole 15 (see
Figure 1 ) to which the tongue is guided by channel 1 1 (see Figure 4).
25 Preferably, tongue hole 15 is sized so that the tongue has to stretch
somewhat to contact the palate 34. When the tongue tip and the
anterior bend of the palate just behind the front teeth are encouraged to
contact each other, the sensory stimulus of both sensory-nerve rich
structures is sufficiently rewarding as to encourage repeated further
30 contact, thus rewarding the desired conduct of positioning the tongue at
a position that is ideal for initiating a correct swallow.
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g
The corrective device 20 can be manufactured in a wide
range of sizes. However, a limited number of sizes should accommodate
most patients. In fact, one universal size accommodates most children or
adults older than four years of age. This embodiment is generally built to
5 accommodate mouths having up to about 50 mm to about 55 mm
separating the outer edges of the second baby molars or bicuspids. The
corrective device 20 is constructed of a resilient solid plastic such as
acrylic, including methacrylate, polycarbonate, such as Lexan (General
Electric, Pittsfield, MA) polyarmomatic carbonate, or another polymer of
10 comparable strength, biocompatability, moldability or bondability. It is
preferably manufactured by injection molding.
The portion of the teeth-fitting segment 2 that rests
under the upper incisal edges of the front teeth preferably includes a
marking designating the center line of the device. The marking can be,
15 among other things, a notch, crease, cavity, nob or a colored line. The
marking can be an alignment projection 12 adapted to fit in front of the
front teeth and having a protrusion 13 adapted to sit in the depression
between the two front teeth ~12 and 13 are visible in Figure 4). Where
the patient's front teeth do not adequately identify the center line of
20 patient's mouth, facial markers such as the nose or chin may be used to
visually align the device.
The teeth-fitting segment 1 is sufficiently planar to allow
stable contact, on both sides of the patient's mouth, with the occlusal
surface of upper posterior (or buccal) teeth of the patient. The portion 2'
25 of the teeth-fitting segment 1 that fits under some or all of the upper
front teeth is used to facilitate fitting the device to a patient. This
forward subportion 2' creates a stabilizing third point of contact between
the device and patient's upper front teeth, the other two points of
contact being between (a) first occlusal trough 3 and the upper posterior
30 teeth located on the patient's right side and (b) second occlusal trough 4
and and the upper posterior teeth located on the patient's left side. After
fitting, the forward subportion 2', which is not necessary for day-to-day
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use, is preferably cut away. Line 5 defining subportion 2' is selected to
position, after subportion 2' is cut away, the front edge of the appliance
parallel to and contoured to the arch shape of the upper front teeth. The
first occlusal trough 3 and second occlusal trough 4 are used to support
the polymerizable material that is molded to the shape of the patient's
upper posterior teeth to snugly fit the device to the patient.
The teeth-fitting segment 1 preferably fits under at least
two upper front teeth, more preferably at least four upper front teeth.
The teeth-fitting segment will also fit under at least about one upper
10 posterior tooth on each side of the mouth, preferably under at least about
two such teeth on each side. After the polymerizable material is fitted
to the device 20, the device will conform to the occlusal and side shape
of these posterior teeth.
First lateral molding elevation 7 and second lateral
15 molding elevation 7' preferably fit on the outer side (i.e., the cheek side)
of at least one tooth on each side of the mouth. Preferably the first
lateral molding elevation 7 and second lateral molding elevation 7' each
fit to the outer side of two of the posterior teeth. In a preferred
embodiment, first lateral molding elevation 7 and second lateral molding
20 elevation 7' do not block side access to the first permanent molars (i.e.,
the "six-year" molars). This allows use of the six-year molars to anchor
other orthodontic devices, such as a band, retaining arch wires or
headgear devices for correcting overjets, for instance using buccal molar
tubes attached to the six-year molars.
Generally, for narrow mouths, the lateral molding
elevations can be ground away after they have been used to facilitate the
molding of cured polymer around the patients' teeth. The removal of the
extra material increases patient comfort while sufficient molded, cured
polymerizable material remains to retain the upper posterior teeth.
First hole 9 and second hole 9' found in the teeth-fitting
segment 1 of a preferred embodiment will generally have diameter from
about 2 mm to about 8 mm, preferably from about 4 mm to about 6 mm.
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Generally, first hole 9 and second hole 9' will make up no more than
about 30%, preferably 25%, more preferably 20%, of the total area of
the teeth-fitting segment 1 that fits under the upper posterior teeth. First
hole 9 and second hole 9' preferably have bevelled edges to facilitate
5 bonding between the corrective device 20 and the polymerizable material
used to fit the device to the patient's teeth. These larger diameter
portions act as plugs or undercuts that stabilize the cured polymer from
separating from the preformed corrective device 20. This bonding
stabilization is particularly relevant during the process of molding
10 polymerizable material to conform to the shape of a patient's teeth, at
which point the bond between the appliance and the uncured or partially
cured polymerizable material is generally weaker than it will be after
further curing.
In a preferred embodiment of the corrective device 20,
15 the palatal bridge 6 is adapted to avoid contacting the upper palate. In
another preferred embodiment, the downward projection 8 is adapted to
avoid hitting or applying pressure to the patient's lower teeth or jaw
when the patient closes his jaws. Preferably, the downward projection 8
projects far enough to the back of the mouth to prevent the patient from
20 biting behind the corrective device 20.
The corrective device 20 will be fiKed to a patient's
teeth or to a work model made from an impression of the patient's upper
teeth and mouth using a polymerizable material which is preferably light
curable, although other means of curing, such as for example heat curing,
25 chemical curing and pressure curing, may be used. This material, prior to
curing, should have a workable tack so that it can be manipulated yet
will, at least for the short term, maintain a formed shape. A preferred
polymerizable material is a urethanedimethacrylate material. Such a
material is available as TRIAD VLC Provisional (rope form) from Densply
30 of York, PA. When TRIAD rope is used, preferably the appliance is
wetted with a monomer solution such as the urethane-dimethacrylate
monomer of the gel form of TRIAD VLC (Densply) or methyl methacrylate
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monomer (such as the solution sold as Orthodontic Resin, by the L.D.
Cork division of Densply, Milford, DE, TRIAD VLC Bonding Agent from
Densply, or SNAP liquid monomer from Parkell, Farmingdale, NY ) prior to
applying the TRIAD rope material. Wetting with TRIAD VLC Bonding
5 Agent can be conducted as recommended by the manufacturer, which
recommended process includes (a) applying the Bonding Agent, (b)
allowing the applied Bonding Agent to sit for one minute, and (c)
exposing the applied Bonding Agent to a suitable light source for two
minutes. The recommended process is believed to minimize the amount
10 of methylmethacrylate monomer present.
The polymerizable material is fitted onto the upper
surfaces of the teeth-fitting segment 1 that are to be fitted under and
around the posterior teeth, specifically the first occlusal trough 3 and
second occlusal trough 4. Preferably, the material will be firmly anchored
15 to the corrective device by being plugged into first hole 9 and second
hole 9' in the teeth-fitting segments. Preferably, some of the
polymerizable material will be applied to the inner surfaces of the first
lateral molding elevation 7 and second lateral molding elevation 7'.
While not illustrated, it should be recognized that the
20 corrective device 20 can have a first inner lateral molding elevation 17
(not shown) and a second inner lateral molding elevation 17' (not
shown). First lateral molding elevation 17 and second lateral molding
elevation 17' seat to the inner side of the posterior teeth that fit into first
occlusal trough 3 and the posterior teeth that fit into second occlusal
25 trough 4, respectively, to support and contain the polymerizable material.
First lateral molding elevation 7 and second lateral molding elevation 7'
typically extend about 4 to about 8 mm above the floor -- against which
the posterior teeth seat -- of the first occlusal trough 3 or second occlusal
trough 4, respectively. First inner lateral molding elevation 17 and
30 second inner lateral molding elevation 17' typically extend about 2 mm to
about 3 mm above the floor of the first occlusal trough 3 or second
occlusal trough 4, respectively.
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The corrective device 20 is then fitted to the upper
posterior teeth, taking care to visually align the device with the center
line of the upper front teeth or mouth. The device and polymerizable
material are then impressed onto the patient's posterior teeth or a model
thereof, with the cusp tips contacting the floors of the occlusal troughs,
while taking care that the forward portion 2 of the teeth-fitting segment
1 is centered and seated against the patient's upper front incisal edges.
When the device 20 has first hole 9 and second hole 9', during this
molding process, finger pressure can be applied to the polymerizable
material extruding through the first hole 9 and second hole 9' to retain
the polymerizable material and force it to flow around the surfaces of the
patient's teeth, instead of further extruding through the first hole 9 and
second hole 9'. Preferably, the polymerizable material is then partially
cured as it sits engaged with the teeth. If the material is light curable,
this may be done exposing the material to suitable light source, generally
for 1 to 2 minutes. The corrective device 20 is then gently removed and
further cured. Generally, when the polymer is light cured the additional
curing is conducted for about 4 to about 6 minutes. After curing, any
excess of the polymerizable material can be sculpted away.
After this curing and sculpting, on occassion the dental
worker will find that the material conforming to some of the useful fitting
surfaces of the patient's teeth have been removed. The fitting can be
improved by creating a polymer with paste-like consistency in the teeth-
conforming trough and again inserting the patient's teeth to cause the
polymer paste to flow out over the useful fitting surfaces. Such a
polymer paste can be self-curing (chemically) or can be curable by
another method. For instance, the polymer paste can be TRIAD VLC gel
or can be created by first applying Orthodontic Resin (L.D. Cork) and then
adding SNAP self-cure resin (a quick-setting acrylic from Parkell
30 Biomaterials Division, Farmingdale, NY) to create a paste-like consistency.
In the later case, repeated applications of the two components may be
needed to create sufficient polymer paste. In fitting the polymer paste to
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a teeth model, a release material such as vasoline can be used to assure
that the polymer paste does not bond to the model.
Forward portion 2 of teeth-fitting segment 1 is generally
thicker than the floors of the first occlusal trough 3 and second occlusal
5 trough 4. One reason for this thickness is the need for sufficient strength
to support the grinding away of subportion 2'. Another reason is that in
use the remaining part of forward portion 2 will contact the patient's
front, lower incisors. The thinness of the first occlusal trough 3 and
second occlusal trough 4 allows a more stable and even contact, when
10 the patient bites, with the patient's lower front and posterior teeth.
When these thinner portions contact the lower posterior teeth, the force
imparted is evenly countered by the upper posterior teeth against which
the thinner portions rest, allowing these portions to be thinner than
forward portion 2 that encounters net torquing forces from contacting
15 the lower front teeth. Generally, the teeth-fitting segment 1 fits under
the second molars (i.e., the second tooth on each side behind the
canines) and this portion of the teeth-fitting segment has a thickness of
from about 1 mm and about 2 mm; and the portion that fits under the
central two front teeth will preferably have a somewhat greater thickness
20 adapted to allow for more even contact between the device and the
patient's lower teeth. Such a greater thickness can be, for instance,
about 3 mm to about 4 mm. An even bite or lower jaw closure happens
when during a natural bite the lower teeth evenly contact the device 20
at three spaced points, with one such point of contact being with the
25 front teeth, another being with posterior teeth on the right side, and the
third being with posterior teeth on the lelft side.
If the corrective device 20 has a forward portion 2' of
the teeth-fitting segment for forming the forward-most contact of a three
point contact with the upper teeth during fitting, that portion is preferably
30 cut away after the fitting process is complete. In a preferred
embodiment, the corrective device 20 has an indentation in the teeth-
fitting segment along a line defining the minimum amount of the forward
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part of the device that will be cut away after the device is fitted to a
patient's mouth. The indentation facilitates an initial cutting away of the
now unnecessary forward portion 2' of the corrective device 20. After
this initial cutting, the device 20 can be further sculpted by grinding or
5 cutting away the extra material.
The forward portion 2' of the teeth-fitting segment is
preferably cut or ground away until the forward part of the corrective
device (the remaining part of portion 2) seats in the patient's mouth from
about 1 mm to about 3 mm, preferably about 2 mm, away from the
10 position of the tips of the upper front teeth. In this way, the corrective
device will not interfere with any downward and rearward drift of the
teeth for their more ideal eruption, which corrective drift results from
relief from the pressure caused by the tongue thrust habit. The sculpting
preferably leaves a sufficient amount of forward portion 2 of the
15 corrective device 20 positioned to block the patient from moving his or
her lower lip up and behind his or her upper front teeth. With swallow
retraining, which results in the upper front teeth drifting downwards and
rearwards to a more ideal alignment, the device 20 can be further
sculpted so that it does not interfere with the corrective drift and eruption
20 of the upper front teeth.
The tongue thrust corrective device 20 is preferably
worn at least about two to three hours a day (usually after school or after
supper) and all night.
While this invention has been described with an emphasis
25 upon preferred embodiments, it will be obvious to those of ordinary skill in the
art that variations in the preferred devices and methods may be used and that
it is intended that the invention may be practiced otherwise than as specifically
described herein. Accordingly, this invention includes all modifications
encompassed within the spirit and scope of the invention as defined by the
30 claims that follow.
