Patent Document

CROSS REFERENCE TO RELATED APPLICATION  
       [0001]    This application claims the priority of U.S. Provisional Application No. 60/223,034, filed Aug. 4, 2000, which is incorporated herein by reference. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The invention relates to a dispenser and a method of using such. More particularly, the invention relates to a thermoplastic dispenser and a method of using the same. Even more particularly, the invention relates to a thermoplastic dispenser for dispensing thermoplastic in a softened, usable state, and a method of using such, such as with a dental impression tray.  
           [0003]    This dispenser would have applications in the dental field, as well as in any other commercial, medical, or private use.  
         BACKGROUND OF THE INVENTION  
         [0004]    The use of thermoplastics in the field of dentistry is known.  
           [0005]    Conventionally, hardened or semi-hardened thermoplastics are used in the making of dental impressions, for example.  
           [0006]    Thermoplastics are also used as material to build up regions of castings that serve as the basis for making dentures.  
           [0007]    In order to melt or soften thermoplastics in the conventional dental office or laboratory, a dedicated water bath, which may be a so-called crock pot, such as found in the domestic kitchens, has been used to soften the thermoplastic. Alternatively, it has been known to heat up a cup of water in a microwave oven to a temperature of 150° F. or more, and then carry the hot cup of water into the room where the dentist or technician is working the thermoplastic material.  
           [0008]    Currently in the dental field thermoplastic is typically used in the form of pre-formed wafers, such as so-called TEMP-TABS™ which are heated in use.  
           [0009]    There is also known thermoplastic which is incorporated in a triple tray or dental impression tray, such as a so-called THERMO-TRAY™.  
           [0010]    Both the TEMP-TABS™ and the THERMO-TRAY™ must be softened in hot water, as discussed above.  
           [0011]    This heating in the dental office not only leads to the problems discussed above, but if the thermoplastic is improperly or overheated, it may develop undesirable bubbles in the overheated thermoplastic. Further, the TEMP-TABS™ are very costly and, even if a relatively small quantity of TEMP-TABS™ are required for a procedure, such may be cost prohibitive.  
           [0012]    Unformed thermoplastic is a relatively inexpensive material.  
           [0013]    Needless to say, such prior art devices and methods of heating and using heated thermoplastic material are impractical, if not unwieldy.  
           [0014]    Still further, prior art dental impression trays are known, such as shown in U.S. Pat. No. 4,619,610 to Pelerin, which is incorporated herein by reference for its description of its FIGS.  1 - 5 , set forth herein as PRIOR ART FIGS.  1 - 5 , and which discloses the use of a conventional dental impression tray.  
           [0015]    Pelerin &#39;610 describes a dental impression tray DIT, having a rigid material RM on one side thereof, and an impression material IM on another side thereon. A known gauze G extends across the width of dental impression tray DIT. In an attempt to prevent distortion of the dental tray DIT first cross braces CB1 are integrally formed with the side wall.  
           [0016]    Flexing of the side wall is undesirable because such leads to a distortion of the impression of the patient&#39;s tooth which is pressed into the impression material IM in use.  
           [0017]    Pelerin provided a second cross brace CB2 which may be secured to the side wall as shown in prior art FIG. 4, and as described in Pelerin &#39;610. Drawbacks of Pelerin &#39;610 remain.  
           [0018]    The practitioner must locate cross brace CB2 so that it does not interfere with the process of making an impression.  
           [0019]    Further, the practitioner must contend with the unavoidable drawback that Pelerin gauze G distorts when the patient&#39;s teeth press down upon it. The gauze G distorts because the gauze, which in practice is produced as a mesh having open holes therethrough, is made of a series of elements extending in a first direction and a second series of longitudinal elements extending in a second direction perpendicular to the first direction. Thus, the pressure exerted by the patient&#39;s teeth cause distortion of the impression material as well as the sides of the tray DIT.  
           [0020]    And, as discussed above, trays such as the Pelerin tray tend to be relatively expensive.  
           [0021]    A known method of making a custom impression tray is shown in U.S. Pat. No. 5,213,498 to Pelerin.  
           [0022]    Accordingly, there is a need for a device or method of using such device that overcomes the drawbacks of conventional devices.  
         OBJECTS AND SUMMARY OF THE INVENTION  
         [0023]    It is an object of the invention to provide a thermoplastic heating device and method of using such that overcome the drawbacks of the prior art.  
           [0024]    Another object of the invention is to provide a thermoplastic heating device which is easier to use, more wieldy, and which accurately heats thermoplastic material, as compared with prior art devices and methods.  
           [0025]    A still further object of the invention is to provide a thermoplastic heating device and a method of using the same.  
           [0026]    Yet another object of the invention is to provide a combined thermoplastic dispenser and water bath.  
           [0027]    A further object of the invention is to provide a thermoplastic dispenser which accurately dispenses controllable amounts of preheated thermoplastic material.  
           [0028]    Yet another object of the invention is to provide a dental impression tray and method of making such which overcomes the drawbacks of prior art trays.  
           [0029]    Yet another object of the invention is to provide a dental impression tray which yields distortion free impressions of teeth, in use.  
           [0030]    Yet anther object of the invention is to provide a dental impression tray which is easier and less expensive to use, and is more versatile than prior art devices.  
           [0031]    A still further object of the invention is to provide a dental impression system which incorporates the features above.  
           [0032]    These and other objects have been achieved, as evidenced by the following.  
           [0033]    The inventive device includes a dispenser for retaining and dispensing a first material; and a reservoir disposed adjacent the dispenser, the reservoir being configured for retaining a second type of material. A heater may be provided for heating a first material retained in the dispenser.  
           [0034]    A method of dispensing a dental material including the steps of providing a dispenser for retaining and dispensing a first material, the first material being a dental material; and providing a heater for heating a first material retained in the dispenser, the heater being provided adjacent the dispenser.  
           [0035]    A method of making a bite tray includes the steps of:  
           [0036]    a) providing an empty bite tray having a first side, a second side, and strands extending between a first side and a second side;  
           [0037]    b) providing a softened material; and  
           [0038]    c) covering the strands at least in part with the softened material.  
           [0039]    A method of making a bite tray, includes the steps of:  
           [0040]    a) providing an empty bite tray having a first side, a second side, and strands extending between a first side and a second side;  
           [0041]    b) providing a solid material;  
           [0042]    c) covering the strands at least in part with the softened material; and  
           [0043]    d) the step of covering the strands includes laying the solid material on an upper surface of the strands.  
           [0044]    A dental tray according to the invention includes:  
           [0045]    a) a first side and a spaced apart second side; and  
           [0046]    b) a plurality of strands extending between the first and second sides.  
           [0047]    A dental tray system according to the invention includes:  
           [0048]    a) a tray including a first side and a spaced apart second side;  
           [0049]    b) a plurality of strands extending between the first and second sides; and  
           [0050]    c) a solid piece of dental material being disposed on said plurality of strands. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0051]    FIGS.  1 - 5  illustrate a prior art dental impression tray DIT, such as shown in U.S. Pat. No. 4,619,610 to Pelerin;  
         [0052]    [0052]FIG. 6 illustrates a first preferred embodiment of a dental impression tray according to the invention;  
         [0053]    [0053]FIG. 7 illustrates another preferred embodiment of a dental impression tray according to the invention;  
         [0054]    [0054]FIG. 8 illustrates another preferred embodiment of a dental impression tray according to the invention;  
         [0055]    [0055]FIG. 9 illustrates a still further preferred embodiment of a dental impression tray according to the invention;  
         [0056]    [0056]FIG. 10 illustrates a strand forming part of a yet still further preferred embodiment of a dental impression tray according to the invention;  
         [0057]    [0057]FIG. 11 illustrates a pre-hardened thermoplastic insert according to the invention;  
         [0058]    [0058]FIG. 12 illustrates a PRIOR ART double arch triple tray-NEO TRAY™;  
         [0059]    [0059]FIG. 13 illustrates a TEMP-TAB™ over a tooth to be prepared and an inventive thermoplastic insert on opposing side;  
         [0060]    [0060]FIG. 14 illustrates a PRIOR ART TEMP-TAB″;  
         [0061]    FIGS.  15 - 17  show three different embodiments of thermoplastic dispensers according to the invention. 
     
    
       [0062]    Relative terms, such as up, down, left, and right are for convenience only and are not intended to be limiting.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0063]    FIGS.  1 - 5  illustrate a PRIOR ART device, as described above.  
         [0064]    [0064]FIG. 6 illustrates a first preferred embodiment of a dental impression tray or tray  10 .  
         [0065]    Tray  10  includes a first side  14  and a second side  18  spaced apart therefrom. First and second sides  14  and  18  may be integrally joined at one end thereof.  
         [0066]    One or more strands  22  and  26  may extend between sides  14  and  18 . Strands  22  and  26  may be made of a synthetic material. The synthetic material may selected for its affinity (i.e., propensity to bond with) a dental impression material  30  disposed on strands  22  and  26 .  
         [0067]    Strands  22  and  26  may be free of linking members (other than first and second sides) which extend between strand  22  and  26 . In that manner when a patient&#39;s teeth bite down on impression material  30  and, hence, strands  22  and  26  disposed thereunder or therein, strands  22  and  26  will move toward or away from each other depending on the location of the portion of the patient&#39;s tooth exerting pressure on a portion of the strand.  
         [0068]    Unlike PRIOR ART devices, such as described in connection with FIGS.  1 - 5  above, the length, size, spacing, and material of strands  22  and  26  may be selected so that under pressure from a patent&#39;s tooth, in use, there will be little or no tendency for first side  14  to move relative to second side  18 . In other words, sides  14  and  18  will not distort, thus causing the impression material  30  to distort.  
         [0069]    In known dental impression trays, there is a tendency for the opposing sides to move toward each other under pressure, and then “spring back” after the pressure is released, thereby distorting the impression of the patient&#39;s tooth that was made in the impression material.  
         [0070]    A handle  34  for assisting in the manipulation of tray  10  may be provided.  
         [0071]    [0071]FIG. 7 illustrates a further preferred embodiment of a portion of a dental impression tray  50 . Tray  50  includes strands  52  and  56  which extend at a greater angle relative to the sides to which they are attached, as compared with the angle defined by strands  22  and  26  of tray  10  of FIG. 6.  
         [0072]    [0072]FIG. 8 illustrates a further preferred embodiment of a tray  60 . Tray  60  includes hook-like openings  66  in at least one of its side walls. Hook like opening  66  are configured for receiving impression material  30  wherein when material  30  is in a softened and hardened state, to assist in retaining the impression material within the tray and relative to the side, for example.  
         [0073]    [0073]FIG. 9 illustrates a further preferred embodiment of a tray  70  according to the invention. Tray  70  includes one or more hook like elements  76  extending outwardly away from one or more of the sides of the tray. Hook like elements  76  are configured for engaging impression material  30 . FIG. 9 shows that, in use, extra impression material may be added in a region  78  outwardly of the free ends of the sides of tray  70 . In that manner, the rigidity and distortion-free properties of tray  70 , as well as other trays according to the invention described herein may be enhanced.  
         [0074]    [0074]FIG. 10 illustrates yet another preferred embodiment of a portion of a tray  80  according to the invention. In tray  80 , only a single strand  82  of which is illustrated for clarity, strand  82  itself may be provided with one or more hooks  86  and  88 .  
         [0075]    Hooks  86  and  88  may all extend outwardly away from the main body  84  of strand  82  at a common angle and orientation, or hooks  86  and  88  may be provided at various locations and extending at various angles and heights, relative to main body  84 , as shown.  
         [0076]    [0076]FIG. 11 illustrates a premade thermoplastic insert  100  which may be used for converting a double arch triple tray into a rigid tray. By use of the novel premade insert  100  the dental impression tray can be completed on-site (e.g., in the dental practitioner&#39;s office) immediately prior to obtaining an impression of a patient&#39;s teeth in a less expensive and a more accurate manner than by using the prior art devices.  
         [0077]    [0077]FIG. 12 illustrates a PRIOR ART double arch triple tray such as a so-called NEO TRAY™.  
         [0078]    [0078]FIG. 13 illustrates the inventive thermoplastic insert  100  in use with the tray of FIG. 12.  
         [0079]    One or more notches  104  provided in thermoplastic insert  100  may be selected to mate with respective prior art extensions on the prior art triple tray. After the dental practitioner places the insert  100  into an existing triple tray, for example, such would be placed in a water bath to heat up the insert  100  sufficiently, so that when the combination is removed from the water bath, the rehardening material provided by insert  100  will engage with the triple tray and be ready for use.  
         [0080]    [0080]FIG. 14 illustrates a TEMP TAB™ wafer.  
         [0081]    Use of the thermoplastic inserts is as follows.  
         [0082]    The thermoplastic inserts  100  may be premade to fit into various known dental impression trays, such as NEO TRAYS™ and MULTI TRAYS. Inserts  100  may be placed into the tray of FIG. 12 so that the thermoplastic insert is on the opposing side of the tooth to be prepared, as shown in FIG. 13. The tray has then placed in a water bath to soften the thermoplastic as well as a known TEMP TAB™.  
         [0083]    The softened TEMP TAB™ is then adapted over the tooth to be prepared making an impression of the tooth after build-up prior to preparation, as in FIG. 13. Before the temp tab hardens, the tray with the softened thermoplastic insert  100  is placed on the opposing arch pressing it against the opposing occlusal surfaces making an impression of these surfaces into the thermoplastic. The patient is then guided into maximum intercuspation and asked to hold the teeth together in occlusion until the thermoplastic completely hardens, fusing the TEMP TAB™ and the opposing thermoplastic together.  
         [0084]    This techniques converts a regular FIG. 12 arch triple tray into a tray which is rigid and cannot flex and thereby preventing spring back distortion which is a common problem with conventional triple trays. Further, the TEMP TAB™ on the prepared side over the tooth to be prepared acts as a vehicle to drive the wash impression material as well as a matrix to make a temporary.  
         [0085]    The advantages of the tray in conjunction with insert  100  over the known thermo trays is the cost-effectiveness of the insert  100  and the TEMP TABS™. The current thermo tray is very small and only covers a small portion of the arch. The regular triple trays go around the arch making a larger impression making it easier to mount the cast, when one step mounting systems are not used. Also, the TEMP TABS™ incorporated into the tray will serve as a matrix to fabricate a temporary as well as a vehicle to drive the wash impression material assuring a good impression of the margins and prepared tooth without risking pulls or voids.  
       FIGS.  15 - 17   
       [0086]    FIGS.  15 - 17  illustrate several preferred embodiments of thermoplastic or thermal plastic dispensers according to the invention.  
         [0087]    [0087]FIG. 15 illustrates a first preferred embodiment of a thermoplastic dispenser  200 . Dispenser  200  may include a heating element  204 , a dispenser  208  and a water bath  220 . Water bath  220  may be disposed substantially adjacent to  208  and provided on a common base  224 , as illustrated. A dispenser nozzle  228  may be provided and sized for general laboratory use or specifically sized for dispensing a thermoplastic material  230  onto a dental impression tray  10  of FIG. 6, for example.  
         [0088]    Thermoplastic material  230  may be dispensed in a molten or semi-molten state by pressing on an actuator portion or pressing device  240  operatively connected with dispensable material  230 . An integral or removable loading element  250  may be provided for ease of filling dispenser  200  with thermoplastic material to be dispensed. As shown, thermoplastic material may be provided in various degrees of softness or liquefaction in a region fluidly connecting dispenser  228  and actuator  240 .  
         [0089]    [0089]FIG. 16 illustrates another preferred embodiment of a dispenser  300  according to the invention. Dispenser  300  may include a nozzle  328  and a handle  334 . An actuator or trigger  342  may be configured for being pressed by the user&#39;s finger or fingers. As in the embodiment of FIG. 15, a region  350  may be provided in which thermoplastic material is loaded for being softened or liquified. Loading region  350  may be sized for receiving cartridges of thermoplastic material.  
         [0090]    [0090]FIG. 17 illustrates a yet still further preferred embodiment of a thermoplastic dispenser  400 .  
         [0091]    Dispenser  400  may be a free-standing device, in a manner analogous to dispenser  200  of FIG. 15.  
         [0092]    Yet, dispenser  400  may be configured as a relatively tall dispenser, similar to the shape of known upright, free standing toothpaste dispensers.  
         [0093]    Dispenser  400  may be provided with a heating element  404  including heating coils or thermally conductive elements  414  and a base  424 .  
         [0094]    One or more chambers  434  may be provided in which, for example, cartridges of thermoplastic material or thermoplastic stock may be provided. A dispenser nozzle  448  will be provided along the lines as discussed above, as well as an actuator for causing thermoplastic material to be dispensed.  
         [0095]    While this invention has been described as having a preferred design, it is understood that it is capable of further modifications, and uses and/or adaptations of the invention and following in general the principle of the invention and including such departures from the present disclosure as come within the known or customary practice in the art to which the invention pertains, and as may be applied to the central features hereinbefore set forth, and fall within the scope of the invention or limits of the claims appended hereto.

Technology Category: 1