Patent Publication Number: US-10307658-B2

Title: Mouth guard

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Application No. 62/190,847, filed Jul. 10, 2015, the entire contents of which is expressly incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to a mouth guard that can be easily be custom fitted on-demand. 
     BACKGROUND 
     Many sporting events require that participants wear a mouth guard in order to protect their teeth from damage in case of an impact. There are a wide variety of mouth guard types that can be used. Inexpensive “stock” mouth guards come in pre-set sizes and shapes and may not fit to the particular shape of a user&#39;s mouth. They may also not fit snugly around the teeth, making it more likely that the mouthpiece will fall out. 
     More sophisticated mouth guards include plastics which soften when boiled. These mouth guards can be custom fitted by boiling them to soften the plastic, after which a user can place the mouth guard in their mouth and bite while the plastic is still soft to deform it and create a custom fit. Another further way to manufacture customized mouth guards is to custom manufacture the mouth guard from a separate impression of the wearer&#39;s teeth. This requires that an impression be taken and sent to a manufacturing facility. The mouth guard is then custom formed based on the impression and returned to the user. 
     One particular problem that occurs frequently at sporting events where mouth guards must be worn is that participants forget or lose their mouth guard. If they do not have a replacement mouth guard, they may be prevented from participating in the sport. To avoid this situation, coaches frequently have available a selection of stock mouth guards that can be used. However, these mouth guards cannot be custom fitted to the user at the venue. Even if the stock mouth guards can be customized after a boiling process, it is typically not feasible to boil a mouth guard at the sporting venue. 
     Accordingly, a need exists for a mouth guard which can be easily and quickly custom fitted to a user&#39;s teeth on demand at a sporting event without the need for boiling the mouth guard to soften its material. 
     It is known to provide a mouth guard tray blank along with a two-part putty that can be mixed by a user, applied to the tray of the mouth guard between its facial and lingual walls and then used to take an impression of the wearer&#39;s upper teeth. 
     A drawback to this design is that the user may bite hard enough on the tray during the impression process to displace enough of the impression material that little or no impression material remains between the upper and lower teeth. This compromises both the fit and the degree of protection of the completed mouth guard. A further drawback is that if the mouth guard is too small or positioned incorrectly when the impression is taken, the user&#39;s teeth may be so close to, or even touching the facial wall, that there no impression material will fill this area daring the fitting. As a result, the only side impact protection provided to teeth in such regions comes from the facial wall itself. While the facial wall could be made thicker, this also reduces the ability of the mouth guard to mold to the particular shape of a user&#39;s mouth during the fitting process. There exists a need to provide an improved mouth guard that addresses these issues as well. 
     SUMMARY 
     These and other needs are met by a mouth guard that has an outer U-shaped facial wall mounted on a thin flexible tray. An inner U-shaped inner lingual wall is also mounted on the tray. The facial and lingual walls wrap around the teeth of the upper dental arch. One or more stops are positioned on the surface of the tray so that when the user bites the mouth guard, the biting surfaces of upper teeth adjacent the stops (such as the incisors and molars) are spaced apart from the surface of the tray. To custom fit the mouth guard, a layer of elastomeric impression material is applied to the tray. The user then bites down on the mouth guard and holds the bite until the impression material has sufficiently set for the mouth guard to be removed while retaining the impression. 
     The tray material is preferably thin and flexible enough so that it can take the impression of the lower teeth as they bite onto a tray with uncured impression material on it. The tray can have holes in it sufficiently large for the impression material to flow through the holes when biting pressure is applied to the uncured impression material. The tray can be formed of the same material as the walls of the mouth guard and the stops so that these components can be integrally formed. Alternatively, the tray can be a fabric mesh on which the walls and stops of a different material are mounted. 
     In a preferred configuration, the facial wall is formed of an inner and outer wall that are a few millimeters apart from each other. This spacing provides for a facial wall of the mouth guard that is sufficiently thick to protect the teeth even if the user fits the mouth guard with their teeth right up against the innermost surface of facial wall and without requiring that the entire thickness of the facial wall be formed of the plastic wall material itself. The gap in the double facial wall parts can be left open, filled with impression material during the custom fitting process, or can be pre-filled with an impact absorbing gel material. It can also be sealed during manufacturing to form a gas-filled pneumatic cushion. 
     A custom mouth guard kit can be provided which combines the pre-formed mouth guard parts (e.g., the facial wall, tray, and stops), and a volume of uncured impression material. The impression material is packaged in a way to ensure that it remains uncured until needed, whether by being provided in the form of a two-part putty that does not set until mix, or in a pre-mixed form that is supplied in an air-tight and/or light-tight package and which can be in a separate package and applied by the user when needed or pre-applied to the tray of the mouth guard so that the unit is pre-prepared to take an impression. 
     Coaches or players at a sporting event can have a selection of mouth guard kits available so that they can quickly and easily make a custom fitted mouth guard on-demand at the venue and without having to boil the mouth guard to soften the material. 
     In addition, the custom-mouth guard kit can include an appropriately sized plastic case that is impregnated with a disinfectant, such as Listerine™ or other conventional disinfectants such as chlorhexidine. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  is a top view of a first embodiment of a mouth guard according to aspects of the invention; 
         FIGS. 2A and 2B  are a cross-sectional views along the line  2   a - 2   a  and  2   b - 2   b  of  FIG. 1 ; 
         FIGS. 2C and 2D  are alternative embodiments of  FIGS. 2A and 2B ; 
         FIGS. 3A /B through  5 A/B show the various stages of the application of impression material to the mouth guard of  FIG. 1 ; 
         FIGS. 6A and 6B  show an alternative embodiment with pre-applied impression material; 
         FIG. 7  shows an alternative embodiment of a mouth guard according to aspects of the invention; 
         FIGS. 8A and 8B  show cross-sectional views along the lines  8   a - 8   a  and  8   b - 8   b    FIG. 7 ; 
         FIGS. 9A-9B  show the embodiment of  FIGS. 8A and 8B  with impact material therein; 
         FIG. 10  shows an embodiment of a mouth guard in which the stops are connected to the facial wall. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Turning to  FIG. 1  and  FIGS. 2A and 2B  there is shown a top view of a first embodiment of a mouth guard  10  according to various aspects of the invention. The mouth guard  10  is comprised of a facial wall  12  and a tray  14 . The facial wall  12  is generally U-shaped to match the general shape of a person&#39;s upper dental arch and defines an interior space  13 . The facial wall has a top  12   a , a bottom  12   b , an inner surface  12   c , and an outer surface  12   d . Facial wall  12  may be formed of plastic or other conventional materials. Facial wall  12  is sized so that when the mouth guard  10  is worn, the facial wall  12  covers facial surfaces of at least some of the upper teeth of a person wearing the mouth guard. Preferably the facial wall  12  covers at least a person&#39;s upper incisors, upper canines, and upper pre-molars. 
     Extending inward into the interior space  13  from the bottom  12   b  of facial wall  12  is a generally flat thin and flexible tray  14 . Tray  14  and extends into the interior space  13  a sufficient distance to extend generally past the biting surfaces of the upper teeth that would be covered by the mouth guard when worn and is also preferably generally U-shaped. 
     The mouth guard further has an inner lingual wall  38  on the tray  14 . Lingual wall  38  is also generally U-shaped and defines an inner boundary of the interior space  13  creating a gap wide enough for the user&#39;s teeth to fit into when the mouth guard is worn. 
     The tray  14  is preferably formed of a textured mesh material that most preferably has numerous openings, such as vias or holes  15 , running from the top to the bottom surfaces of the tray in at least the areas which are not covered by the facial and lingual walls  12 ,  38  at and that are sufficiently large to permit impression material to flow into and/or through then as discussed further below. The tray  14  does not need to be comprised of the same material as the facial wall  12 . In a preferred embodiment, the tray is comprised of a flexible thin plastic fabric-like mesh on which the facial wall  12  and lingual wall  38  are mounted, such as shown in  FIGS. 2A and 2B . 
     The facial and lingual walls  12 ,  38  can be made of the same material as each other. Further, facial and lingual walls  12 ,  38  may be made of the same material as the tray  14  and all three components integrally formed, such as shown in  FIGS. 2C and 2D . 
     In addition, and as shown in  FIGS. 1 and 2B , mouth guard  10  has one or more stops  16  on the tray  14  which extend above the surface of the tray and are preferably at least twice the thickness of the tray. The stops are positioned and sized so that at least part of the top surface of the stop will be generally adjacent the biting surfaces of one or more upper teeth when the mouth guard is worn. When the wearer bites down on the mouth guard, the stops preserve a gap between the upper teeth and the tray. Preferably there are at least three stops, one of which is generally adjacent a wearer&#39;s incisors while stops the other two are on the left and right sides generally adjacent the wearer&#39;s molars or pre-molars such as stops  16   a ,  16   b , and  16   c  shown in  FIG. 1 . 
     As with the facial wall, the stops can be discrete components affixed to the tray as shown in  FIG. 2B . Alternatively, the stops can be made of the same material as the tray  14  and integrally formed with the tray as shown in  FIG. 2D . 
     Preferably the stops  16  are separate from the facial wall  12  and lingual wall  38  with gaps  17  and  39 , respectively, there between. Thus, as shown in  FIG. 1 , stop  16   a  and the facial and lingual walls  12 ,  38  define gaps  17   a  and  39   a . In an alternative configuration, particularly suitable if the tray  14  is not integrally formed with the walls  12 ,  38 , the stops  16  could alternatively be formed as extensions of the facial wall  12  and/or lingual wall  38 . This configuration would reduce the number of separate components in the mouth guard and to make it easier to place the stops.  FIG. 10  shows a configuration where the stops  16  are attached to the facial wall  12  by a bridge  52 . Preferably, the bridge is lower than the height of the stop. It can also be narrower than the stop as shown in the figures. The stops can also be connected to an inner lingual wall  38  in addition to or alternatively to being connected to the facial wall. 
     To customize the mouth guard for use by a particular individual, a layer or bead of uncured elastomeric dental impression material  18  is applied to the top of the tray  14 . The impression material may be a polyvinyl or silicon rubber composition, or other impression materials known to those of skill in the art. Preferably, sufficient impression material is applied to substantially cover the tray  14  and the stops  16 .  FIGS. 3A and 3B  show impression material  18  applied in this manner. 
     After the impression material  18  is applied to the tray, and as shown in  FIGS. 4A and 4B , the mouth guard  10  is placed into the user&#39;s mouth, and the user bites down on it. The biting pressure applied by the wearer&#39;s upper teeth  20   a ,  20   b  and lower teeth  22   a ,  22   b  deforms the uncured impression material so that it takes an impression of the contours of the user&#39;s teeth. The stops  16  prevent the user from closing their mouth too tightly and preserves a layer of impression material  18  of about at least the height of the stops between the upper and lower teeth and above the areas of the tray  14 . 
     The tray  14  is sufficiently flexible to take an impression of the lower teeth  22   a ,  22   b  as the user&#39;s mouth is closed. As shown in  FIGS. 4A and 4B , when the user bites, the tray  14  flexes and generally follows the contours of the biting surfaces of the user&#39;s lower teeth  22   a ,  22   b . In addition, preferably there are openings, such as holes or vias, in the tray  14  sufficiently large so that uncured impression material placed on the top surface of the tray  14  flows into the holes when the biting pressure is applied so that the impression material  18 , when cured, is securely affixed to the tray. Most preferably, the holes are large enough so that the impression material  18  can flow through the tray  14  to take an impression of the lower teeth. 
     After the impression material  18  has cured sufficiently to generally retain its shape, the mouth guard  10  can be removed from the user&#39;s mouth. As shown in  FIGS. 5A and 5B , the result is a mouth guard that has been customized to the user&#39;s mouth and in which a minimum thickness of impression material has been preserved the top surface of the tray by the action of the stops. The mouth guard can be fitted quickly and on-demand without boiling or other heat treatments at sporting events where mouth guards may be required. 
     There are a variety of ways in which the impression material  18  can be provided for use. In one configuration, the mouth guard  10  is provided as part of a custom mouth guard kit in which a volume of uncured impression material  18  sufficient for use with at least one mouth guard as disclosed herein is included. 
     Various types of conventional elastomeric impression materials known to those of skill in the art can be used. In one embodiment, the impression material is a 2-part material, such as polyvinyl siloxane, in which each component comes in the form of a soft putty. The user would simply mix the two putties together, apply them to the mouth guard, and take the impression. The set time of conventional polyvinyl siloxane is about three to five minutes. Preferably, a no-mix or pre-mixed monophase impression material is used. Conventional monophase impression materials such as Genie™ VPS impression material from Sultan Healthcare and Reprosil® VPS impression material from Dentsply. 
     In a particular embodiment, the impression material can be pre-mixed and of a type that will cure when exposed to air or light, such as visible or ultraviolet light. This impression material would be provided within an airtight and/or light-tight or other suitable packaging to prevent the impression material  18  from curing before its packaging is opened. For example, the impression material can be provided in tube from which it can be squeezed onto the tray. In another embodiment, a roll of impression material tape can be provided that can be applied and pressed onto the tray. In a further embodiment, a block of impression material pre-shaped to place into the tray can be provided. 
     In a further alternative embodiment, shown in  FIGS. 6A and 6B , a layer  24  of impression material is pre-applied to the top of the tray  14  of mouth guard  10 . Preferably a layer  26  is also pre-applied to the bottom of the tray  14 . The pre-applied impression material can also pass through the vias  15  in the tray  14  to help the top and bottom layers  24 ,  26  of impression material remain attached. In this configuration the utility of the vias to allow material to flow through from the top to the bottom of the tray as an impression is being taken is reduced since impression material is already present on the bottom of the tray. As such the number of vias can be reduced (or even eliminated). The mouth guard  10  with pre-applied impression material can then be placed in a sealed package, such as a plastic or foil packet with a peelable lid. When a new mouth guard is needed, the user need only open the package, apply the impression material to the tray (if not already pre-applied), bite down on the mouth guard to create the impression, and wait a short period of time for the impression material to cure. 
     The mouth guard kit also preferably includes an appropriately sized plastic case that can be impregnated with a disinfectant, such as Listerine™ or other conventional disinfectants such as chlorhexidine. The case can be provided separately from the mouth guard and impression material or form part of the packaging for the mouth guard kit with the mouth guard (and impression material if pre-applied) contained therein. 
     For a mouth guard to provide protection from side impacts, the mouth guard should not be too thin along the sides. It can be appreciated that when a user is making a tooth impression in the mouth guard  10 , the user might position the mouth guard in then mouth so that the facial surfaces of some of the teeth are immediately adjacent the inner surface  12   c  of the facial wall  12 . The result is that the only protection from side impacts provided in this area is by the facial wall itself. To provide adequate protection, the facial wall itself may need to be relatively thick. In addition, the lack of impression material may compromise the fit of the mouth guard in this area. 
     According to a further aspect of the invention, and as shown in  FIG. 7  and  FIGS. 8A and 8B , the facial wall  12  is comprised of an outer wall  32  and an inner wall  34  with a gap  36  in between them. The use of this double wall allows the material forming the facial wall to remain thin while ensuring that there is a greater distance between the outside of the mouth guard and the user&#39;s teeth in order to provide additional protection from side impacts. The gap  36  between the inner and outer walls  32 ,  34  is preferably between 3.5 and 5 mm and preferably. As shown in  FIGS. 9A and 9B , the gap  36  preferably is filled with an impact absorbing material  40 . 
     In one configuration, the impact absorbing material  40  is same material as the impression material  18  and can be applied by the user at the same time as uncured impression material is applied to the tray  14  or pre-applied within the gap  36 . This would allow the facial wall  12  of the mouth guard  10  to mold somewhat to the specific shape of the user&#39;s upper dental arch. Alternatively, a different type of impact material  40  can be placed in the gap  36 . 
     In a further alternative embodiment, tops and ends of the outer and inner walls  32 ,  34  can be connected to each other and sealed during manufacturing to form a gas-filled pneumatic cushion.