U.S. patent application number 10/563894 was filed with the patent office on 2007-08-02 for orthodontic activator.
This patent application is currently assigned to LM-Instruments Oy. Invention is credited to Katri Keski-Nisula, Juha Varrela.
Application Number | 20070178420 10/563894 |
Document ID | / |
Family ID | 27636075 |
Filed Date | 2007-08-02 |
United States Patent
Application |
20070178420 |
Kind Code |
A1 |
Keski-Nisula; Katri ; et
al. |
August 2, 2007 |
Orthodontic activator
Abstract
An odontological device and device series to guide an
individual's occlusion and a method to be used in selecting an
occlusion guidance appliance device to be used in orthodontic
treatment. This kind of device contains a U-shaped arch with a
lower surface on the side of the lower jaw and a higher surface on
the side of the upper jaw, and in both of which there are concaves
in which to place the individual's teeth, and where the bottoms of
the concaves form of the isthmus separating the concaves from one
another. According to the invention, the isthmus includes blanks
meant for individual teeth and uniform, continuous hollows meant
for at least two teeth to guide the teeth in the required
direction, and the lower jaw side surface has a lower wing
constricting the tongue at least sideways, and it helps the device
to remain in place in the individual's mouth. The blanks position
the device at the teeth and the dental arch, the compartments
reduce the problems caused by twisted teeth when inserting the
device in the mouth for example and the lower wings help to keep
the device in place.
Inventors: |
Keski-Nisula; Katri; (Vaasa,
FI) ; Varrela; Juha; (Turku, FI) |
Correspondence
Address: |
WOLF BLOCK SCHORR AND SOLIS-COHEN LLP
250 PARK AVENUE
NEW YORK
NY
10177
US
|
Assignee: |
LM-Instruments Oy
PL 88
Parainen
FI
FI-21601
|
Family ID: |
27636075 |
Appl. No.: |
10/563894 |
Filed: |
July 7, 2004 |
PCT Filed: |
July 7, 2004 |
PCT NO: |
PCT/FI04/00434 |
371 Date: |
June 1, 2006 |
Current U.S.
Class: |
433/6 |
Current CPC
Class: |
A61C 7/08 20130101 |
Class at
Publication: |
433/006 |
International
Class: |
A61C 3/00 20060101
A61C003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 7, 2003 |
FI |
20031038 |
Claims
1. An odontological device for guiding the occlusion of an
individual, said device comprising: a generally U-shaped arch made
of flexible material and that has a lower surface on the lower jaw
side and an upper surface on the upperjaw side, and in both of
which there are concaves for receiving the individual's teeth, the
bottoms of the concaves forming an isthmus which separates the
concaves from one another, wherein the isthmus includes blanks
intended for individual teeth and uniform, continuous recesses for
at least two teeth to guide the teeth in the required direction,
and the lowerjaw side surface has a lower wing constricting the
tongue at least sideways, and it has been shaped to further
placement of the device in the individual's mouth.
2. An odontological device according to claim 1, wherein said
recesses contain uniform compartments that begin from the second
premolar and continue towards the molars at least partly to the
area where the second permanent molar will erupt.
3. An odontological device according to claim 2, wherein the side
walls of said uniform compartments are formed by outer and inner
walls, respectively, which have essentially straight walls.
4. An odontological device according to claim 2, wherein said
compartments are shaped like continuous troughs, and the troughs
are open from the molar side end.
5. An odontological device according to ally of claim 1, wherein
said recesses contain uniform recesses limited to the area of the
front teeth, and the surface walls of the recesses are essentially
smooth.
6. An odontological device according to claim 1, wherein said
concaves have their own blanks for canine teeth and the first
premolars.
7. An odontological device according to claim 1, wherein said
isthmus separating the concaves is thicker at least in the area of
the molars than in the area of the front teeth.
8. An odontological device according to claim 7, wherein said
isthmus thickness changes stepwise at the point between the
premolars.
9. An odontological device according to claim 7, wherein said
isthmus is essentially even in such a way that its thickness in the
narrower area is essentially in fixed range of approximately 1 to
10 mm and 3-13 mm, respectively, in the thicker area.
10. An odontological device according to claim 1, wherein the walls
of the concaves are formed by the outer walls on the labial side or
on the buccal side, respectively, and by the inner walls on the
opposite sides of the concaves on the lingual side, the inner wall
on the lowerjaw side surface being continued so that it is at least
essentially aligned downwards to the wall surface in such a way
that it extends lower than the corresponding outer wall to form
said lower wing.
11. An odontological device according to claim 10, wherein said
lower wing has been arranged to reach the immediate proximity of
the base of the mouth cavity.
12. An odontological device according to claim 11, wherein said
shape of the lower wing, particularly in the molar area, follows
essentially the shape of the lower side jaw arch.
13. An odontological device according to claim 10, wherein the
downwards dimension of the mentioned lower wing has been reduced at
the point of the ligament of the tongue.
14. An odontological device according to claim 13, wherein said
lower wing extends approximately at the point of the first molar to
a distance of 14 mm as a maximum of the down side surface of said
isthmus, in which case said distance is approx. 3 to 6 mm smaller
in the area of the ligament of the tongue.
15. An odontological device according to claim 10, wherein the
outer wall on the upper jaw side surface has been at least
partially continued upwards at least essentially aligned upwards to
the wall surface in such a way that it extends above the gum
line.
16. An odontological device according to claim 15, wherein said
upper side outer wall extends essentially above the gum line at
least in the area of the first and second tooth, and preferably
also in the area of the third and fourth tooth.
17. An odontological device according to claim 15, wherein said
upper outer wall extends at its highest point to approx. 10 mm from
the distance of the upper side surface of said isthmus.
18. An odontological device according to claim 1, wherein when the
upper side arch, measured essentially along the base of the arch
and between the second and third tooth, is approx. 32 mm, the
length of the compartment starting from the second premolar and
terminating in an open end is 22 mm on the upper side and 24 mm on
the lower side, and correspondingly, when the length of the
mentioned arch is 37 mm, the length of the compartment is 24 mm on
the upper side and 27 mm on the lower side.
19. An odontological series of devices, containing a series of
essentially conformal devices of different sizes, wherein the
devices correspond to an odontological device according to claim
1.
20. A series of devices according to claim 19, wherein the upper
side arch of a device in the series, measured along the base of the
arch and between the second and third tooth, is less than about 26
mm, the maximum distance of the lower wing lower edge to the
equivalent point on the surface of the isthmus between the
masticating surfaces is approximately 8 to 10 mm, and when the
mentioned arch is over 26 mm said maximum distance is about 14
mm.
21. An odontological device series according to claim 19, wherein
when the upper side arch of a device in the series, measured
essentially along the base of the arch and between the second and
third tooth, is approx. 32 mm, the length of the mentioned
compartment starting from the second premolar and terminating in an
open end is 22 mm on the upper side and 24 mm on the lower side,
and correspondingly, when the length of the mentioned arch is 37
mm, the length of the compartment is 24 mm on the upper side and 27
mm on the lower side.
22. A device series according to claim 19, wherein the smallest
device in the series has the mentioned arch length of less than 26
mm and the largest 36 mm as a minimum, preferably at least of
approx. 38 mm.
23. A device series according to claim 19, wherein the length of
the smallest device in the series, measured from the wall on the
lingual side of the front teeth to the line connecting the open
ends of the molar areas, is essentially less than 40 mm and the
upper side front wall at least 5 mm high.
24. A method in orthodontics for selecting an occlusion guidance
appliance device, according to which method at least one
characteristic measurement is defined for an individual's teeth,
and based on this measurement an appropriate device is selected for
that individual, comprising the steps of: measuring the length of
the upper jaw side dental arch from the individual's teeth between
the left and right hand side front and middle teeth or two middle
teeth, choosing, based on the measurement without taking separately
into consideration the developmental phase of the teeth, a suitable
occlusion guidance appliance devices from one of the occlusion
guidance appliance device series according to one of claims 19 to
23, which contains several essentially conformal and
different-sized occlusion guidance appliance devices.
25. A method according to claim 24, wherein the measurement of the
dental arch is taken from the anatomy along the outer surface and a
device is selected based on the resulting measurement, the arch
measurement of which is 1-2 mm smaller than the measurement
according to the anatomy.
Description
[0001] The present invention concerns an odontological device
according to the preamble of claim 1 for guiding the occlusion of
an individual.
[0002] This kind of device usually comprises a U-shaped arch that
has a lower surface on the lower jaw side and an upper surface on
the upper jaw side, both of which have teeth-receiving concaves.
The device is made of a flexible and elastic material, such as a
thermoplastic elastomer, plasticized (softened) plastic or rubber
or of a similar material.
[0003] The invention, furthermore, concerns an occlusion guidance
device series according to the preamble of claim 19 as well as a
method according to the preamble of claim 24 for selecting a device
for occlusion guidance in orthodontic treatment. In the method, at
least one characteristic measurement is defined for a person's
teeth, and an appropriate device is selected for the person based
on this measurement.
[0004] The treatment method by which to achieve the required
occlusion is also described in the description of the
invention.
[0005] Odontological occlusion guidance appliances, orthodontic
braces and equivalent odontological devices are used fairly
commonly to treat and eliminate problems such as supraocclusion,
rotations and individual cross-bites. Previously known devices are
dental braces made of steel and teeth positioning devices made of
flexible materials. In the latter ones, i.e. the (so-called)
occlusion guidance appliances, there are typically concaves for the
teeth of the lower and upper jaw that are separated by an isthmus
that has recesses, so-called "blanks", formed for the individual
teeth. With these blanks individual teeth can be guided to the
required place and position. Devices of a kind, where a part of
said blanks has been replaced with compartments intended for more
than one tooth, are also known. The devices have been designed and
are meant to be used mainly during the phase when the milk teeth
are being replaced by adult teeth and after the adult teeth have
erupted. The occlusion guidance appliances are meant to be used
passively, particularly during the night, but in difficult or
complex cases they are recommended to be used also for 1-4 hours
during the daytime. The manufacturing material in the known
technology has normally been plasticized (softened) polyvinyl
chloride.
[0006] Occlusion guidance appliances have been presented, for
example, in published patent applications nos. WO 02/062253 and WO
02/062252, FR Patent Specification No. 1 104 897 as well as in U.S.
Pat. Nos. 4,784,605, 4,799,884, 4,830,612, 4,919,612 and 5,879,199,
the contents of which are herewith incorporated by reference.
[0007] U.S. Pat. No. 4,830,612 presents an occlusion guidance
appliance designed for children of ages 2-6, where the incisors,
canine teeth and the first middle teeth each have their own blanks.
A single, continuous and uniform compartment has then been formed
for the second middle tooth and first molars. The device is meant
to be used before the milk teeth come out and is appropriate only
for the milk teeth, since the device ends before the second molar.
In the description and the claims it has been emphasized that the
device should at a maximum extend to the point where the first
molar will erupt. This kind of device cannot be recommended for use
by older children, because there is a danger that the second molar
will over-erupt and cause an open occlusion. If one wants to
continue the treatment of the patient even after the permanent
teeth have erupted, the device must be replaced by another device
designed for that phase of development. The use of many different
kinds of occlusion guidance appliances will be expensive for the
patient and will require the manufacturer and the dentist to have a
wide range of products.
[0008] In addition to the above-mentioned problems, there are also
other disadvantages related with the known solutions. Typically, it
is difficult to get the occlusion guidance appliance to remain in
the correct position in the mouth, for example, when the person is
sleeping and the lower jaw very easily "drops" and retracts
somewhat. This could lead to the patient biting the device from the
inside of the lower edge, in which case the device is not working
as it should, and is in fact guiding the positioning of teeth
towards a different direction than originally intended. In
addition, the device, if not properly positioned in the mouth, may
be easily bitten during daily use to the point where it breaks.
[0009] In WO Publications Nos. 02/062253 and 02/062252 a device is
disclosed, which is meant for positioning the teeth and in which
the inner wall of the lower jaw side concave extends downwards in
such a way that it forms a tongue ramp. This is designed to
partially encircle the tongue from underneath. The publication has
no mention of using the tongue ramp, for example, to further the
stationary position of the occlusion guidance appliance.
[0010] Further, the problem in known solutions is that the
occlusion guidance appliances have been designed to be used in a
particular developmental phase of the teeth. In this case, the
device to be used has to be chosen not only according to the size
of the teeth but also from a variety of different devices. On top
of the problems of selecting the device and the frequency of
changing it, there is also the added costs arising from a need to
maintain a large range of products.
[0011] It is an aim of the present invention to remove
disadvantages associated with known technology and to create a
completely new kind of way of treating the occlusion of a person.
The objective of the invention is particularly to form an occlusion
guidance appliance that will remain properly positioned in the
mouth in different use environments and in different ways of use,
including when being worn by small children. In addition, it is an
aim to enable the guiding of the occlusion using an essentially
similar-shaped device both in the milk tooth phase and in
subsequent phases.
[0012] Furthermore, it is an objective to provide a series of
occlusion guidance appliances that are appropriate for use in all
developmental phases of the teeth, in which case the appropriate
device can be chosen and/or it can be changed to another one, only
on the basis of the size of the person's dental arch.
[0013] Thus, it is also an aim of the invention to provide a new
method in orthodontics to be used for selecting the occlusion
guidance appliance, one where the appropriate occlusion guidance
appliance is easily selected, based on a simple measurement, from
one type of device without having also to consider the
developmental phase of the teeth.
[0014] The invention is based on the idea that treatment results
can be improved by providing an occlusion guidance device with
wings and other structures that ease the use of the device and
particularly help to keep it stationary in the mouth. We have
concluded that by forming these kinds of wings in a suitable manner
we can also ensure that a person cannot gradually bite through the
device while using it. With the shaping of the wings it is also
possible to ensure that even teeth erupting very obliquely can be
guided inside the device. In the orthodontic activator according to
the invention it is thus essential that at least one wing is
arranged to form a lower wing on the lower surface of the occlusion
guidance appliance. This lower wing, which is formed as an
extension of the inner/lingual side wall on lower jaw side concave
in the device, constricts the tongue at least sideways.
Advantageously, the device includes also a wing on the labial side
of the upper teeth, suitably extending over the gum line.
[0015] The introduction of the device into the mouth and its use
can also be facilitated, particularly if the device is further
provided with uniform compartments for some of the teeth, instead
of individual blanks. This can be done particularly in cases where
the aim is mainly to align the teeth in the required place, rather
than to precisely guide into a specific position. The use of
compartments shared by more than one tooth will ease placing the
device in the mouth, particularly in some cases where the occlusion
is not correct, such as when the front tooth or teeth are twisted.
However, according to the invention, it is not advantageous to use
only one compartment along the length of the entire dental arch,
since it is not possible to achieve the necessary precision
required of the orthodontics to position the device correctly in
the mouth merely with the aid of the wings and by having a
correctly curved device.
[0016] In the orthodontic activator according to the invention, the
isthmus interconnecting the concaves for the upper and lower jaw
therefore contains uniform areas for one or more tooth groups.
These shared areas include particularly compartment-like recesses.
In addition to this, the device advantageously includes individual
blanks at least for one tooth of each quarter of the teeth, and
these blanks further the correct placement of the occlusion
guidance appliance in relation to the teeth.
[0017] As a result of its structure, the device according to the
invention is suitable for children of all ages, particularly those
between 5 and 15 years. A device series intended for anatomies
(dental arches) of different dimensions can be manufactured such
that there is always a device of a suitable size available for any
individual.
[0018] The series can be used in a method for selecting an
occlusion guidance appliance to be employed in orthodontics. In
this method, firstly at least one characteristic measurement of the
individual's teeth is defined, and an appropriate device is
selected for the individual from the series of occlusion guidance
appliance devices based on this measurement. The invention is
characterized in that the measurement is the length of the dental
arch, which is measured from the upper jaw side dental arch on the
left and right side, particularly between the second and third or
possibly third and fourth teeth. Based on the resulting measurement
a suitable occlusion guidance appliance device is selected.
[0019] More specifically, the odontological device according to the
invention is characterized by what is stated in the characterizing
part of claim 1.
[0020] The series of odontological devices according to the
invention is characterized by what is stated in the characterizing
part of claim 19.
[0021] The method according to the invention is characterized by
what is stated in the characterizing part of claim 24.
[0022] By means of the invention and its preferred embodiments
significant advantages can be achieved. In such a device, as a
result of the combination of compartments, blanks and lower wings
according to the invention, even small children can easily put the
device in their mouths so that it is reliably in the correct place.
The blanks position the device on to the teeth and the dental arch,
the compartments reduce problems caused by twisted teeth when
inserting the device in the mouth, for example, and the lower wings
help to keep the device in place. Thanks to the lower wing
construction, the device is more likely to remain intact because
the wings prevent the front teeth biting together to the extent
that they could cut through the device and in turn make it
difficult to turn the device in the mouth, so that the possibility
of biting through the edges is reduced.
[0023] In one preferred embodiment of the device, the upper lip
side edge of the occlusion guidance appliance has been raised in
such a way that it extends at least partially above the gum line.
In this way, good guidance of the teeth is also obtained in
difficult cases, and the device will sit more comfortably in the
mouth.
[0024] According to one preferred embodiment of the invention, the
groups of teeth have been provided with compartments particularly
in the area of the first molar and at least partially in the area
where the second molar will erupt. With this solution, open
occlusion problems possibly caused by over-eruption of the second
molar can be diminished or even prevented.
[0025] The invention enables the use of an occlusion guidance
appliance with the same basic structure all the way from the milk
tooth phase to the guiding of the occlusion of the permanent teeth.
A series of essentially conforming devices will be made from the
device, and in everyone of these the same basic solutions are used
so that an appropriate device is chosen for the individual under
treatment according to the length of the dental arch. In this
context, "conforming" means that the devices have the same basic
structure, they preferably have compartments, blanks and wings
arranged with respect to the teeth recesses. The individual devices
of the device series can also geometrically conform to each other,
but this is not necessary when constructing a device series meant
to treat occlusion.
[0026] A device according to the invention can be used both for
milk teeth, changing teeth and permanent teeth. Thus, the cost of
orthodontics is reduced when the patient is not required to use a
new occlusion guidance appliance in each developmental phase of the
teeth, rather the device needs to be replaced by a new one only as
a result of dental arch growth.
[0027] The device according to the invention essentially works for
everyone. It can be used in treating both horizontal and vertical
overbite as well as the narrowness of the front area and of
rotations and individual cross-bites. In addition, a device
according to one application form of the invention is also suitable
for treating open occlusion.
[0028] The advantages of the uses of the embodiments of the
invention have been described also in copending Finnish patent
application (Purennanohjain ["Occlusion guidance appliance"]) filed
at the same time with this application, and incorporated by
reference.
[0029] The invention and its other preferred embodiments will be
considered more closely as follows, with the help of detailed
explanations referring to the attached drawings.
[0030] FIG. 1 shows in perspective view the upper jaw side of one
occlusion guidance appliance according to the invention;
[0031] FIG. 2 shows in perspective view the lower jaw side of one
occlusion guidance appliance according to the invention;
[0032] FIG. 3 shows an occlusion guidance appliance according to
one embodiment of the invention in relation to its position in
anatomical use position viewed from the back side;
[0033] FIG. 4 shows section A-A of FIG. 3; and
[0034] FIGS. 5a and 5b show an upper image of an occlusion guidance
appliance according to the invention and respectively an image
according to FIG. 3 of device dimensions with measurements.
[0035] An occlusion guidance appliance according to the presented
invention consists of a U-shaped arch 1, made of elastic and
suitably flexible material such as thermoplastic elastomer,
plasticized (softened) plastic or rubber, and is roughly shaped
like a horseshoe. Accordingly, its shape corresponds at least
mainly to the dental arch of the patient. The occlusion guidance
appliance has an upper surface 2 and a lower surface 3, of which
the upper surface 2 includes the formation of receptive concaves 4
for the teeth of the upper jaw. Equivalently, the lower surface 3
includes a formation of concaves 5 for the teeth of the lower jaw.
They are at least sufficiently wide and deep to be able to fit the
teeth of the patient at least for the mainly visible parts. Their
edges do not necessarily completely extend beyond the gum line. The
walls of the concaves form the upper and lower side outer walls 4a
and 5a on the side of the lips and correspondingly on the side of
the cheeks, and in relation to these from the upper and lower side
inner walls 4b and 5b on the opposite sides on the tongue side
shaped As FIGS. 1 and 2 show, the bottoms of concaves 4 and 5 are
formed by the isthmus 14 separating the concaves, in which hollows
have been formed, that is, blanks 6a-6d; 7a-7d for the canine teeth
and the first premolars. The thickness of isthmus 14 can be only 1
mm, but according to the advantageous embodiments of the invention
it is significantly thicker than this, even 10 mm. By arranging the
canine teeth and first premolars in their own blanks, the device
can be positioned precisely enough in the mouth of the patient,
even though the device contains uniform and common spaces for the
other teeth groups shaped The hollows of a device according to
FIGS. 1-4 extending to the back teeth consist of uniform
compartments 8, 9, 10 and 11, which start from the second premolar
and continue towards the molars at least to the area where the
second permanent molar will erupt. Advantageously, the uniform
compartment totally covers the area of the second permanent molar.
The compartment can in principle be continued beyond this point,
but in practice it has been noted that the device will function
fully satisfactorily if space is arranged for three teeth, namely
the second premolar and the first and second molar. Extended
devices are usually not as comfortable as the devices shown in the
drawings, which end in the second molar.
[0036] According to the preferred embodiments of the invention, the
side walls 4a, 4b, 5a and 5b of these uniform, continuous
compartments 8-11 are formed equivalently of the outer and inner
walls 8a, 8b and 9a, 9b, 10a, 10b, and 11a, 11b, which have
significantly straight or slightly curved walls lengthways. On the
inner surface, the walls are smooth in such a way that they have
not been significantly profiled with tooth forms. Compartments 8-11
are thus shaped like continuous open troughs, the troughs being
open from the molar-side end. Seen from above, the compartments are
roughly shaped like rectangles.
[0037] The outer and inner walls of compartments 8-11, marked in
FIGS. 1 and 2 with reference numbers 8a, 8b, 9a, 9b, 10a and 11a,
slightly taper towards the edges ending up at the rounded edge. The
upper side walls 8a and 9a rise in the front area of the dental
arch at least to the gum line and are otherwise higher than the
inner side walls 8b and 9b. As graphic 1 shows, the elevation of
the device upper outer wall 8a and 9a continues at least
significantly in the same direction with the other wall surface.
Advantageously, the outer walls 8a and 9a can cover the gum line at
least in the area of the first and second tooth, preferably in the
area of the third and even the fourth tooth. With the presented
solution the risk that the front upper jaw teeth erupt over the
edge of the device can be avoided or at least significantly
reduced. The rising of the front wall 4a (8a, 9a) thus guides the
upper front teeth to erupt inside the concave and at the same time
the device will remain more comfortably in the mouth. According to
the size of the dental arch, this outer wall extends to at least
about 5 mm, typically approximately and even over 10 mm, of the
distance of the mentioned isthmus 14 and, thus, depending on the
isthmus thickness used, even to about 15 mm of distance from the
middle level of isthmus 14.
[0038] As explained below in more detail, the inner side wall 5b on
the lower surface of the device has been continued downwards
towards the base of the mouth cavity. The form of this side wall 5b
at the point 10 and 11b of the molar compartments is slightly
different from that of the other walls, as its walls are at least
essentially evenly thick and taper only near the edge. In the area
of the front teeth, the wing turns more strongly away from the
teeth and it has been narrowed suitably below the teeth, at the
point of the gum, which improves the use comfort (preventing the
vomit reflex). From the cross-section of graphic 4, these and the
other forms of the lower wing come out very clearly.
[0039] The cross-section of FIG. 4 shows these and the other forms
of the lower wing very clearly.
[0040] In the device according to FIGS. 1-4, the device has uniform
hollows 12 and 13 in the area of the front teeth in the same way as
the previously described uniform troughs 8-11 in the molar area.
The equivalent walls of these hollows, marked in the graphics 1 and
2 with reference numbers 12a, 12b, 13a and 13b, are at least for
the main part smooth-surfaced, that is, at least largely
un-profiled. Mainly at least in the area of these hollows 12 and 13
the isthmus 14 between them is mainly even, that is, without any
blanks arranged for individual teeth.
[0041] Instead, in the walls 12a, 12b, 13a, and 13b, in some
embodiments of the invention, it can be foreseen to be arranged not
actual clear forms but mainly small lightening features can be
arranged in the places of the front teeth.
[0042] Seen from above and below, the walls are curved in such a
way that they conform to the natural shape of the dental arch.
Along the upper edge they can, however, be shaped to follow the
teeth. The uniform hollow of the front teeth (first and second
teeth) eases the placing of the device in the mouth compared to
arranging a blank that is measured for each individual tooth. This
is true particularly when the front teeth are twisted.
[0043] FIGS. 3 and 4 show the isthmus 14 separating the upper and
lower side concaves 4 and 5. The figures also show how the lower
wing formed from the lower tongue-side inner wall 5b extends
deepest into the area of the first molar and, moreover, is lower in
the area at the front. The isthmus 14 between the upper and lower
side compartments 8-11 can be evenly thick or it can be made
narrower in the area of the molars, as U.S. Pat. No. 4,830,612
describes. According to one embodiment of the invention, the
isthmus 14 in question is thicker in the molar area than elsewhere.
This solution aims at correcting open occlusion. More precisely, in
this case the otherwise essentially even isthmus has a step at the
point between the fourth and fifth teeth each side. According to
the invention, when the height of the step in question is of a
magnitude of 2-3 mm, this means the minimum isthmus thickness of
approximately 1 mm and 3 mm in the front and back teeth area and a
maximum of approximately 10 mm and 13 mm, respectively.
[0044] In this embodiment, "thickness" refers to the distance
between the surfaces that go against the upper and lower teeth.
[0045] As stated above, the lower jaw side inner wall 5b of the
device has been continued according to the invention to be at least
essentially aligned with the surface of the wall in question in
such a way that it extends lower in the mouth cavity than the
corresponding outer wall 5a. This inner wall 5b, which is also
called "the lower wing" in this application, can advantageously
extend, in some parts at least, essentially to the immediate
vicinity of the base of the mouth cavity in the area of the first
molar.
[0046] The lower wing limits the tongue in the surface on the lower
jaw side at least sideways, by which means the device more easily
remains in place in the patient's mouth, as the following will
indicate in more detail. The lower wings keep the lower jaw in
place at the front, thus avoiding the drawback of known devices
causing lower jaw "dropping", which is explained above in the
introduction to the explanation. For their part, the lower wings
can also prevent sideways movement of the device, which is affected
also by the walls on the cheek-side of the device. In order for the
lower wing to fit in the mouth of the patient in the best possible
manner, the introduction downwards can be arranged to be smaller at
the point of the ligament of the tongue than elsewhere.
[0047] In the advantageous application form of the invention, the
lower wings have been formed to be slightly curved towards the
teeth of the lower jaw, and the edge of the flexible wall follows
fairly precisely the shape of the lower jaw arch. In addition, at
the front teeth, the starting angle in relation to the vertical
plane can be greater than elsewhere, thereby ensuring that it does
not press the gum excessively.
[0048] FIGS. 1 to 4 show details of the favourable application form
of the invention. The cavities 15 formed in the front part of the
U-shaped arch in the direction of the sagittal plane can be
separately mentioned. The cavities go through the walls of the
arch. The cavity holes help breathing, particularly when the
patient is sleeping.
[0049] The U-shaped arch has been made of silicon polymer or of
plasticized polyvinyl chloride. It is particularly advantageous to
use liquid silicon as the raw material.
[0050] A series can be made of several different-sized devices
according to the invention. In the light of the measurements shown
in graphics 5a and 5b, this kind of series can contain for example
13 orthodontic activators having the dimensions specified in Table
1. The relative dimensions of the smaller devices intended to be
used mainly in the milk tooth phase can be somewhat different from
the other devices in the series. Nevertheless, all the devices in
the series still contain contours according to the essential
characteristics of the invention and (relative) dimensions. The
measurements presented in Table 1 are exemplary "approximate"
measurements, but they do describe the essential dimensions of the
device. TABLE-US-00001 TABLE 1 Typical measurements of one device
series according to the invention, formed of different size
orthodontic activators 1. Length of 4. Length of molar 6. Length
upper 3. Edge compartment.sup.4) of the incisor 2. Lower of mm 5.
Width of device.sup.6) Device hollow.sup.1) wing.sup.2) lip.sup.3)
upper lower the device (depth) # mm mm mm side side mm mm 1 24 8 5
16 19 52 35 2 25 9 7 18 20 53 38 3 26 13 10 20 23 55 40 4 27 13 10
20 23 55 42 5 28 13 10 20 23 55 42 6 30 13 10 20 23 56 44 7 31 14
10 22 24 57 47 8 32 14 10 22 24 58 47 9 33 14 10 22 25 60 48 10 34
14 10 23 26 61 48 11 35 14 10 23 26 62 48 12 36 14 11 24 27 63 51
13 38 16 11 25 28 64 53 .sup.1)Length measured along the bottom of
the hollow, essentially along the centre line of the arch formed
.sup.2)Maximum length measured from the surface of the lower molar
compartment in the back area .sup.3)Maximum length of the upper
front wall measured approximately between the first and second
tooth on the surface of the upper side hollow .sup.4)Length from
the front edge of the molar compartment to its open end .sup.5)The
maximum distance between the molar compartment outer edges
.sup.6)The length between the line connecting the open ends of
molar compartments and the front surface of the front wall
[0051] From Table 1, it can be seen that when talking about devices
according to the invention for use by individuals in the changing
teeth phase and also by older individuals, the maximum measurement
of the lower wing is of a magnitude of about 14 mm and that of
the-upper side lip edge is about 10 mm--measured from the bottoms
of the hollows, that is, always according to the isthmus thickness
used, respectively, about 1-6 mm or more measured from the centre
point of the masticating surfaces/isthmus.
[0052] When the arch of a device in the series, measured along the
centre line of the arch and between the second and third tooth, is
less than about 26 mm, the maximum distance of the lower edge of
the wings to the equivalent point on the surface of the isthmus
between the masticating surfaces is approximately 8 to 10 mm, and
when the mentioned arch is over 26 mm the mentioned maximum
distance is about 14 mm. When the arch is about 32 mm, the length
of the compartment starting from the second premolar and
terminating in an open end is approx. 22 mm on the upper side and
on the lower side approx. 24 mm; and equivalently when the length
of the arch is approx. 37 mm, the length in the upper side is
approx. 24 mm and in the lower side approx. 27 mm.
[0053] Typically, the length of the arch of the smallest device in
the series is less than 26 mm and that of the largest device a
minimum of 36 mm, preferably at least 38 mm. And when the arch
length of the mentioned smallest device, measured along the centre
line of the arch and between the second and third tooth, is
essentially less than approx. 40 mm, the upper side front wall is
at least 5 mm.
[0054] A device according to the invention is used for orthodontic
treatment in an analogous way, in contrast to the known devices
(see for example U.S. Pat. Nos. 4,830,612, 4,799,884 and
4,919,612). In the method, a suitable occlusion guidance appliance
device is chosen for each individual from previously described
series of devices. Thus, first the length of the dental arch on the
upper jaw side is measured--either between the second and third
tooth or between the third and the fourth tooth--and a suitable
sized device is chosen from the series formed of devices according
to the invention on the basis of the measurement. The measurement
is taken along the outer surface of the anatomy (the dental arch),
and the arch measurement of a suitable device is 1-2 mm smaller
than this as it is based on the measurement defined along the base
of the isthmus. Selecting the device is thus solely based on the
size of the jawbone and a new device is taken into use only on the
basis of how the jawbone will grow, independent of how the teeth
have otherwise developed.
[0055] The device selected is used by biting it actively between
the teeth. A method according to the invention can particularly be
applied and the device used already at the milk tooth phase and
continued with equivalent but larger devices even after the
permanent teeth have erupted, in order to guide the teeth to grow
and position themselves to achieve a desired, pre-defined
occlusion. The device can be used until the permanent teeth have
fully erupted and when necessary use can be continued by treatment
aiming at maintaining the resulting positioning. Typically, the use
of the device can be started approximately at the age of five
years, and correspondingly stopped at the age of around 15. In some
special cases, use can be continued even to near the age of 20. The
device is used always when sleeping and, when necessary, also
during the daytime. Compared to a device according to a U.S. Pat.
No. 4,830,612, a "changing teeth" device according to the invention
presented is longer than the corresponding known device, and thus
the device can be used also after the second molar has erupted. The
lower wings guide the patient to bite the device correctly. This
reduces device breakage. The lower wings help to keep the device in
the mouth and functioning in the right way.
[0056] Even though it was emphasized earlier that the invention
guides occlusion, it is clear that a device according to the
invention can-always depending on the situation--position at least
a number of the individual's teeth, or guide them to the
pre-determined place or position. This need is served particularly
by the blanks formed for the individual teeth.
* * * * *