Abstract:
A bracket for orthodontic use includes a base having a face adapted to be mounted to an inside surface of a tooth; and a stem having a first end connected to the base, the stem including a spur connected to a second end of the stem such that when the base is mounted to the inside surface of the tooth, the spur is located rearwardly of the face and oriented in the rearward direction. A method for prevention of tongue thrust swallowing includes providing a bracket having a spur, mounting the bracket on a rear surface of a tooth that is substantially opposing the tongue, and orienting the spur in a direction substantially opposing the tongue to discourage tongue thrust during swallowing.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    This invention relates to a method and a device for discouraging tongue thrust swallowing and thus preventing and correcting anterior openbite malocclusions.  
           [0003]    2. Description of the Related Art  
           [0004]    When swallowing, the tongue is first positioned against the front of the palate behind the front teeth, and then it is moved upwards and backwards against the palate. Tongue thrust problems develop as a result of placing the tongue too low and too far forward in the mouth which results in moving the tongue against and in front of the front teeth at the end of swallowing.  
           [0005]    Tongue thrusting may also occur during speech. Recent scientific research has shown that tongue thrusting during swallowing or speech is an adaptive technique that is used to create an anterior seal. During each tongue thrust, the tongue applies pressure to the front teeth for a duration of time. The repeated application of the pressure can contribute to the upward and forward displacement of the upper front teeth and their surrounding bone, which results in the creation of an open space between the upper and lower front teeth. This condition is known as anterior openbite malocclusion.  
           [0006]    [0006]FIG. 1 illustrates the relative positioning of a tongue  50 , upper front teeth  20  and lower front teeth  30 . Upper and lower front teeth shown in FIG. 1 do not exhibit anterior openbite malocclusion. FIG. 1A shows the relative positions of upper front teeth  20  and lower front teeth  30  shown in FIG. 1 in a closed position. In contrast to FIG. 1, upper front teeth  20  and lower front teeth  30  are shown as having the anterior openbite malocclusion condition. Shaded areas  20 A,  30 A indicate the positions that these teeth should have when the mouth is closed. For example, shaded area  20 A shows the position of a normal upper front tooth and the shaded area  30 A shows the position of a normal lower front tooth. An upper molar tooth  10  and a lower molar tooth  10 A are shown to be in contact in order to demonstrate the relative positions of upper front teeth  20  and lower front teeth  30  when the mouth is closed. As shown in FIG. 1A, upper front teeth  20  and lower front teeth  30  are spaced apart greatly.  
           [0007]    To prevent the development of anterior openbite malocclusion various solutions have been proposed. U.S. Pat. No. 5,779,470, for example, has proposed an oral corrective device that is retained by the posterior teeth to condition the tongue to refrain from tongue thrusting during swallowing. The device proposed includes a teeth-fitting segment which is adapted to fit under an upper posterior teeth of a patient, a palatal bridge extending from this segment and adapted so that it may not contact the palate of the patient, and a downward projection adapted to create a rearwardly opening pouch or channel which “engulf” the patient&#39;s tongue. When the device is fitted into a patient&#39;s mouth by tightly fitting it onto the patient&#39;s posterior teeth, the pouch or channel positions the tongue properly and accurately to imitate a normal swallow. To properly employ the device shown, the device must be fitted to a patient&#39;s mouth. The fitting process involves, among other steps, molding a polymerization material onto the device and around the patient&#39;s posterior teeth and then curing the material into a resilient solid conforming to the shape of the patient&#39;s teeth. As is evident this device needs to be customized for each patient which may be costly and time consuming.  
           [0008]    As another solution for preventing anterior openbite malocclusion, a rake-like device may be installed on the back side of upper front teeth of a patient to discourage or prevent the tongue thrust habit. FIG. 2 shows such a device. As shown, rake-like device  60  includes two anchor portions  70 ,  70 A each integrally joined to an end of a main wire  75 , and a plurality of spur portions  80  integrally joined to main wire  75  at one end. In the example shown in FIG. 3, main wire  75  is curved so as to substantially follow the contour of the row of upper front teeth  20 . The spurs include a tip portion  80 A. Tip portion  80 A of each spur is oriented to substantially face the patient&#39;s tongue. Each one of anchor portions  70 ,  70 A is secured around a respective molar tooth  10 ,  10 B, in order to securely mount the device inside of the patient&#39;s mouth. Once mounted, spurs  80  essentially hang off of main wire  75  with tip portions  80 A hanging down from main wire  75  and facing the patient&#39;s tongue. In such a position, tip portions  80 A of spurs  80  intercept the tongue thrust of the patient thereby discouraging the tongue thrust swallowing habit which causes anterior openbite malocclusion.  
           [0009]    Such rake-like devices must also be customized for each patient as the position of the anchoring molar teeth and the number, position and size of the spurs for each patient varies. In addition, the device  60  must be carefully installed to ensure that all spurs  80  substantially face the patient&#39;s tongue, and are positioned substantially behind upper front teeth of the patient to properly intercept the tongue. These customization steps are time consuming and may cause the patient discomfort during the installation of the device.  
           [0010]    In addition, if other corrective devices such as braces are being used on the patient&#39;s teeth, the device will have to be taken out and resized. This situation is demonstrated in FIGS. 3A and 3B. As shown in FIG. 3A, a brace  40  which is installed on the outer surface of upper front teeth of the patient is tightened to close the gaps  45 A,  45 B in the teeth. The direction of the movement of the teeth for closing gaps  45 A,  45 B is shown by the arrows. As gaps  45 A,  45 B are closed, main wire  75  gets closer to the interior surface of upper front teeth  20 . To avoid having main wire  75  run into the interior surface of upper front teeth, device  60  has to be taken out so that main wire  75  can be shortened as shown in FIG. 3B. This too is time consuming, and the re-installation requires adjustments which may cause the patient further discomfort.  
           [0011]    Therefore, it is desirable to have a method for preventing anterior openbite malocclusion through discouragement of tongue thrusting during swallowing. It is also desirable to have a device for discouraging tongue thrusting during swallowing that is convenient to install and adjust to minimize a patients discomfort.  
         SUMMARY OF THE INVENTION  
         [0012]    One aspect of the present invention involves a bracket that includes a base that is adapted to be mountable to an inside surface of a tooth, and a stem having a first end connected to the base. The stem includes a spur connected to a second end of the stem and oriented in a direction away from the face.  
           [0013]    In another respect the present invention involves a method for prevention of tongue thrust swallowing including providing a bracket having a spur, mounting the bracket on a rear surface of a tooth that is substantially opposing the tongue, and orienting the spur in a direction substantially opposing the tongue to discourage tongue thrust during swallowing.  
           [0014]    Other features and advantages of the present invention will become apparent from the following description of the preferred embodiments which refers to the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]    For the purpose of illustrating the preferred embodiments, there is shown in the drawings an embodiment which is presently preferred; it being understood, however, that the invention is limited to the precise arrangements and instrumentalities shown.  
         [0016]    [0016]FIG. 1 is a profile illustration of the relative positioning of an individual&#39;s teeth and tongue.  
         [0017]    [0017]FIG. 1A is a profile illustration of the upper and lower rows of teeth in a closed position.  
         [0018]    [0018]FIG. 2 is an illustration of a row of upper front teeth having installed thereon a device for prevention of anterior openbite malocclusion according to the prior art.  
         [0019]    [0019]FIG. 3A is an illustration of a row of upper front teeth having installed thereon a device for prevention of anterior openbite malocclusion according to the prior art and a brace for closure of gaps between the teeth.  
         [0020]    [0020]FIG. 3B is an illustration of a row of upper front teeth having installed thereon a device for prevention of anterior openbite malocclusion according to the prior art and a brace that has closed the gaps between the teeth shown in FIG. 3A.  
         [0021]    [0021]FIG. 4A is a side view of a bracket according to the present invention.  
         [0022]    [0022]FIG. 4B is a front view of a bracket according to the present invention.  
         [0023]    [0023]FIG. 4C is a back view of a bracket according to the present invention.  
         [0024]    [0024]FIG. 5 is an illustration of a row of upper front teeth having installed thereon brackets according to the present invention and a brace for closing the gaps between the teeth.  
         [0025]    [0025]FIG. 6 is a profile illustration showing the brackets of the present invention installed on the teeth.  
         [0026]    [0026]FIG. 7 is an illustration of a row of upper front teeth having installed thereon brackets according to the present invention and a brace for closing the gaps between the teeth.  
         [0027]    [0027]FIG. 8 is the row of upper front teeth having brackets installed thereon according to the present invention as shown in FIG. 7 after the gaps have been closed. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0028]    Referring now to the drawings wherein like numerals indicate like elements, FIGS.  4 A-C show a bracket  100  according to the present invention. Bracket  100  can be manufactured with any of the known materials using any of the known methods. Bracket  100  includes a base portion  110  and a stem  125 . Stem  125  includes an extension rod  120  and a spur  130 . Base portion  110 , extension rod  120  and spur  130  form bracket  100  having a unitary body.  
         [0029]    Base portion  110  includes a substantially flat surface  115 . A mesh pad  140  is attached to the flat surface  115  of base portion  110  by, for example, casting or welding. Mesh pad  140  is preferably made from stainless steel. Mesh pad  140  is utilized to adhere bracket  100  to a patient&#39;s tooth to retain the same in place, although it is within the scope of the present invention to adhere bracket  100  to a tooth using any other suitable methods.  
         [0030]    Stem  125  is oriented substantially parallel to and spaced away from a surface  115  of base  110 . Spur  130  is formed by bending stem  125  to a desired angle such that the tip  145  of a spur  130  is spaced away from surface  115  of base  110  at a distance. Stem  125  may be made from a semi-malleable material so that it may be bent, cut or otherwise modified to a desired shape and height. Stem  125  may be preferably made with stainless steel. Spur  130  is oriented so that it is projecting away from the plane of surface  115  of base  110  of bracket  100 . Preferably, spur  130  will be oriented substantially along a direction that is perpendicular to the plane of surface  115 . When oriented in this direction tip  145  of spur  130  will be spaced at a maximum distance away from surface  115  of base  110 .  
         [0031]    Base portion  110  includes a base pad  150 . The base pad  150  has a maximum width  155  (FIG. 4C) a maximum height  156  (FIG. 4C) and a thickness  157  (FIG. 4A). Preferably, bracket  100  has a maximum height  160  which is the distance between the outermost position on base pad  150  and the outermost position on extension portion  120 . Maximum width  155  and maximum height  156  of base pad  150  should be such that the area of the surface  115  (and thus the area of the surface of mesh pad  140 ) will be small enough to fit on a surface of an individual tooth. Maximum height  160  of bracket  100  should be small enough so that bracket  100  will not interfere with the closing of the patient&#39;s mouth. Maximum height  160  may be adjusted by cutting stem  125 , or bending its end into a shape of a spur and smoothing the tip of the spur before mounting a bracket onto a patient&#39;s tooth.  
         [0032]    Preferably, stem  125  is comprised of a substantially cylindrical body which has a spur  130  with a dome-shaped distal end, for example tip  145 , as shown in FIG. 4A. The cylindrical body has a substantially uniform diameter. The diameter of the body is preferably about 1 mm. Preferably, the remaining dimensions of the bracket are as follows: thickness of base pad is about 0.25 mm; maximum width  155  of base pad  150  is about 3.5 mm; maximum height  156  of base pad  150  is about 4-5 mm; and maximum height of bracket  100  is about 9.5 mm. Furthermore, the maximum distance between tip of spur  145  and surface  115  of base portion  110  is preferably about 3 mm, and extension portion  120  is spaced about 1 mm away from surface  115  of base portion  110 . Spur  130  is preferably 1 mm in length and a maximum of 1 mm in diameter.  
         [0033]    Referring now to FIG. 5, in use, a plurality of brackets  100 C,  100 D,  100 E,  100 F according to the invention are mounted on the inner surface of frontal teeth of a patient by any of the known methods. The number and location of brackets mounted on a patient&#39;s teeth depend on the severity of the openbite malocclusion and their respective locations. For example, to treat lateral openbite malocclusion, brackets could be mounted on side teeth. Preferably, in an ordinary case of openbite malocclusion, six brackets may be mounted on the upper front teeth, and six on the lower front teeth of the patient. Preferably, brackets  100 C,  100 D,  100 E,  100 F may be mounted by applying a dental adhesive to a mesh pad (not shown) disposed on a base of each bracket and attaching the same to the inner surface of a tooth. The dental adhesives used may be self-cured or light-cured. Dental adhesives commercially available from any of the known suppliers such as adhesives sold under trademarks RELY A BOND™, TRANSBOND™, CONCISE™, and ENLIGHT™ may be used to adhesively mount a bracket  100 . Preferably, light-cured dental adhesives available from any of the know suppliers such as dental adhesives sold by 3M under the trademarks TRANSBOND™XT, and TRANSBOND™LR may be used. The latter are advantageous in that they are cured by application of a UV light after a bracket is positioned in a proper place on a tooth. To apply the UV light, preferably, a light curing unit, such a light curing unit sold by 3M under the trademark ORTHOLU™XT may be used. Of course, other UW-curable adhesives and UV light curing units may be used to adhesively mount a bracket  100 .  
         [0034]    Spurs  130  (see FIG. 4A) of each one of the brackets  100 C,  100 D,  100 E,  100 F may be reoriented as desired by twisting its extension rod  120  or otherwise deforming its stem  125  portion prior to mounting. In this way, the patient may be spared the discomfort of adjustments of the orientation of the spurs. Once mounted, spurs on the brackets  100 C,  100 D,  100 E,  100 F will be opposing the patient&#39;s tongue. The area of a base pad for each one of the brackets  100 C,  100 D,  100 E,  100 F should be large enough to accept enough adhesive to form a strong bond with the surface of the teeth. The shape of the base pad may be such that it furthers this goal. A preferred technique for mounting a bracket  100  is to place bracket  100  on the surface of a tooth directly with a cotton plier and a plugger instrument.  
         [0035]    [0035]FIG. 6 shows a profile view of upper teeth  20  and lower teeth  30  exhibiting anterior openbite malocclusion. As shown, a bracket  100 A according to the present invention is mounted on a tooth in the row of upper front teeth  20  and another bracket  100 B according to the present invention is mounted on a tooth in the row of lower front teeth  30 . It is to be noted that a spur  130 A and spur  130 B are positioned to oppose the tongue.  
         [0036]    Referring to FIGS. 7 and 8, when brackets  100 C,  100 D,  100 E,  100 F are individually mounted on the teeth of a patient who also has a brace  40 , no readjustment of the position of brackets  100 C,  100 D,  100 E,  100 F becomes necessary when brace  40  is readjusted for example to close gaps  45 A,  45 B (as shown by the arrows) between the teeth. When the brackets  100 C,  100 D,  100 E,  100 F are mounted on teeth that are not repositioned by the closing of the gaps between the teeth. This is because, unlike the rake-like device of the prior art which needs to be adjusted to ensure the proper positioning of its spur portions (see FIGS. 3A and 3B) when the brace is adjusted, the position of the brackets do not need to be changed. This also spares the patient the discomfort of adjustment and reinstallation which is normally associated with rake-like devices. Additionally, a method of prevention of openbite malocclusion according to the present invention also provides more room for a patient&#39;s tongue because the brackets are placed flush against the teeth instead of being located on a wire (e.g.,  75 , FIG. 2) set away from the teeth.  
         [0037]    Although the present invention has been described in relation to particular embodiments thereof, many other variations and modifications and other uses will become apparent to those skilled in the art. It is preferred, therefore, that the present invention be limited not by the specific disclosure herein.