Patent Document

TECHNICAL FIELD 
     The present invention relates to a dental capsule 
     BACKGROUND 
     It is known to provide dental capsules containing dental powder and liquid in separated condition. The powder and liquid components are typically admixed by any convenient means and the capsule is subsequently placed in a mixing device. In the mixing device the components are thoroughly admixed to form a dental paste suitable for application to a tooth for treatment thereof. 
     It has now been discovered that it is possible to admix the components of a dental capsule simultaneously with vibration thereof. 
     SUMMARY OF THE INVENTION 
     In accordance with one aspect of the present invention there is provided a dental capsule comprising means for storing dental powder and liquid components in separated condition having a hollow body with a first end and second end, wherein the powder component is contained in a compartment of the hollow body adjacent the first end of the capsule and the liquid component is contained in a pouch adjacent the second end of the hollow body, the second end of the hollow body being provided with a chamber having an open outer end and a partially closed inner end, the chamber having mounted therein the pouch, a restraining cup being mounted in the open end of the chamber, the restraining cup having a closed outer end and an open inner end, the pouch being retained in place by engagement between the inner end of the cup and the inner end of the chamber, the cup further containing an unrestrained member disposed between an outer end of the cup and the pouch, the unrestrained member being arranged to move reciprocally within the cup when the capsule is vibrated in a vibrating mixer so as to impact against the pouch so as to rupture the pouch at the partially closed inner end of the chamber to enable the liquid component to admix with the powder component to form a dental paste simultaneously with vibration wherein the compartment of the hollow body adjacent the first end thereof is provided with a manually removable cup. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will now be described, by way of example, with reference to the accompanying drawings, in which: 
         FIG. 1  is a transverse sectional view of a capsule in accordance with the present invention in exploded condition; 
         FIG. 2  is a transverse sectional view of the capsule of  FIG. 1  in assembled condition; 
         FIG. 3  is a view similar to  FIG. 2  with the capsule in activated condition; 
         FIG. 4  is a view of the capsule of  FIG. 2  in a separated condition after mixing has taken place; 
         FIG. 5  is a transverse sectional view similar to  FIG. 1  of a further embodiment of the capsule in accordance with the present invention; 
         FIG. 6  is a transverse sectional view of the capsule of  FIG. 5  in assembled condition; 
         FIG. 7  is a view similar to  FIG. 6  with the capsule in activated condition; and 
         FIG. 8  is a view of the capsule of  FIG. 5  in a separated condition after mixing has taken place. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In  FIGS. 1 and 2  of the accompanying drawings there is shown a dental capsule  10 , having a main body  12  and a removable cap  14 , arranged to engage with an end of the body  12 . 
     The body  12  has an internal circumferential flange  16 . The cap  14  has an inner end  15  which engages with one side of the flange  16  as shown in  FIG. 2 . The cap  14  and the adjacent end of the body  12  form part of a chamber  17  containing a dental powder component  13 , in use as seen in  FIGS. 2 and 3 . 
     Further, a liquid containing pouch  18  is mounted within a chamber  20 . The chamber  20  has an outer open end  22  and a partially closed inner end  24  as shown in  FIG. 2  containing a relatively small aperture  25 . The chamber  20  engages with a side of the flange  16  opposite that engaged by the cap  14 . The pouch  18  is mounted in the chamber  20  as will be described. 
     As shown in  FIG. 1 , the pouch  18  comprises a pair of opposed layers  26  which are typically formed of film. As shown one layer  26  is flat and the other is recessed so that the pouch  18  defines a volume  19  containing a liquid component  28 . However, the volume  19  could be defined by the other layer  26  being recessed or by both layers  26  being recessed. The volume  19  is sized so as to hold an amount of liquid component compatible with the amount of the powder component in the chamber  17 . 
     Edges  27  of the layers  26  forming the pouch  18  may be ultrasonically welded or laser welded or heat sealed together. Thus, the edges  27  of the layers  26  are then joined together to form a hermetic seal around the liquid containing volume  19 . 
     The layers  26  may be made from mono, di or tri layered film. Film with more than three layers can be used. The flat layer  26  may be made thinner or weaker than the recessed layer  26 . 
     The pouch  18  is retained in place initially by a restraining cup  30  which has an open inner end  32  and a closed outer end  34  as shown in  FIGS. 1 and 2 . As shown the cup  30  engages with the chamber  20 . The inner end  32  of the cup  30  together with the inner end  24  of the chamber  20  sandwiches the edges  27  of the layers  26  in the assembled condition of the capsule  10  as can been seen in  FIG. 2 . 
     As shown, the chamber  17  is defined by the cap  14 , the flange  16  and the inner end of the chamber  20 . 
     Further, the cup  30  contains a freely mounted or unrestrained member  36  which is disposed in the volume between the outer end  34  of the cup  30  and the pouch  18 . The member  36  may be a solid member which fits snugly in the cup  30 . The member  36  may be made of plastics material. The member  36  is smaller longitudinally than the volume defined by the cup  30  and the pouch  18  and is therefore able to move reciprocally within the cup  30  when the capsule  10  is placed in a vibratory mixer. 
     In use, the capsule  10  in assembled condition is inserted in a vibratory dental mixer of known type. As the capsule  10  is vibrated the unrestrained member  36  is moved reciprocally in the volume between the outer end  34  of the cup  30  and the pouch  18 . Thus, the unrestrained member  36  impacts the adjacent layer  26  of the pouch  18  repeatedly. This causes the adjacent layer  26  to be depressed. Further this action causes hydraulic pressure of the liquid component  28  in the pouch  18  to be increased so that the layer  26  of the pouch  18  adjacent the aperture  25  in the inner end of the chamber  20  is ruptured at the aperture  25  as shown in  FIG. 3 . This creates a path for the liquid component  28  to contact powder in the cap  14  for mixing in the chamber  17 . Generally, a mixing time of 5 to 15 seconds such as about 10 seconds is sufficient for the liquid component  28  in the pouch  18  to be forced into the chamber  17 . 
     After mixing the cap  14  may be removed manually as shown in  FIG. 4  so that mixed dental paste  38  can be accessed. 
     The capsule  50  of  FIGS. 5 to 8  is an embodiment which is similar to that of  FIGS. 1 to 4  and like reference numerals denote like parts. 
     In the capsule  50  the flange  16  supports a partition  52  containing a central aperture  54 . The partition  52  forms an inner end of the chamber  17  and is integrally formed with the flange  16 . Further, a layer  26  of the pouch  18  is disposed adjacent the aperture  54 . 
     In this embodiment the pouch  18  is retained in place initially by a retaining cup  30  which has an open inner end  32  and a closed outer end  34 . The inner end  32  of the cup  30  engages with the partition  52  as shown in  FIG. 6  and sandwiches the edges  27  of the layers  26 . In this embodiment the chamber  17  is defined by the cap  14 , the flange  16  and the partition  52 . 
     In this embodiment, construction of the capsule is very similar to that of the embodiment of  FIGS. 1 to 4 . In this case a layer  26  of the pouch  18  adjacent the aperture  52  is ruptured as shown in  FIG. 7 . 
     The mixed dental paste  38  in this activated capsule can be retrieved in similar manner to that of  FIGS. 1 to 4  by manually removing the cap  14  as shown in  FIG. 8 . 
     Modifications and variations as would be apparent to a skilled addressee are deemed to be within the scope of the present invention.

Technology Category: 1