Slotted plunger

1. Plunger, for use in a receptacle for holding material to be discharged having flat front and rear faces with a discharge opening on the front face, comprising a plunger body having a rear flat face and a front flat face, wherein the rear face and the front face of the plunger largely correspond to the interior of the receptacle front and rear faces, and wherein the plunger body comprises at least two surrounding sealing lips which each have slot-shaped notches at least at one point, which notches permit a gas exchange between the receptacle interior and the outside atmosphere as soon as the plunger has moved into a fitting receptacle.

2. Plunger according to claim 1 , wherein the plunger body has a barrel-shaped construction.

3. Plunger according to claim 1 , wherein the sealing lips each have two slot-shaped notches.

4. Plunger according to claim 2 , wherein the sealing lips each have two slot-shaped notches.

5. Plunger according to claim 1 , wherein the slot-shaped notch or notches of one sealing lip are arranged offset to the slot-shaped notch or notches of the other sealing lip.

6. Plunger according to claim 2 , wherein the slot-shaped notch or notches of one sealing lip are arranged offset to the slot-shaped notch or notches of the other sealing lip.

7. Plunger according to claim 3 , wherein the slot-shaped notch or notches of one sealing lip are arranged offset to the slot-shaped notch or notches of the other sealing lip.

8. Plunger according to claim 4 , wherein the slot-shaped notch or notches of one sealing lip are arranged offset to the slot-shaped notch or notches of the other sealing lip.

9. Plunger according to claim 1 , wherein the front face of the plunger has a cross-sectional surface that corresponds essentially to the inside diameter of the receptacle.

10. Plunger according to claim 2 , wherein the front face of the plunger has a cross-sectional surface that corresponds essentially to the inside diameter of the receptacle.

11. Plunger according to claim 3 , wherein the front face of the plunger has a cross-sectional surface that corresponds essentially to the inside diameter of the receptacle.

12. Plunger according to claim 5 , wherein the front face of the plunger has a cross-sectional surface that corresponds essentially to the inside diameter of the receptacle.

13. A method for closing receptacles containing pasty masses and discharging the masses from these receptacles wherein the receptacles have flat front and rear faces with a discharge opening on the front face comprising inserting a plunger body into the receptacle, wherein the plunger body has a rear flat face, a front flat face, wherein the rear face and the front face of the plunger largely correspond to an interior of the receptacle, and wherein the plunger body has at least two surrounding sealing lips which each have slot-shaped notches at least at one point, and wherein the notches permit a gas exchange between the receptacle interior and the outside atmosphere.

14. Method according to claim 13 , wherein the receptacle has a predominantly cylindrical interior.

15. Method according to claim 13 , wherein the plunger body has a barrel-shaped construction.

16. Method according to claim 13 , wherein the sealing lips each have two slot-shaped notches.

17. Method according to claim 13 , wherein the slot-shaped notch or notches of one sealing lip are arranged offset to the slot-shaped notch or notches of the other sealing lip.

18. Method according to claim 13 , wherein the front face of the plunger has a cross-sectional surface that corresponds essentially to the inside diameter of the receptacle.

19. Receptacle having a flat front face, an outlet on the front face and a plunger displaceably disposed therein which comprises a plunger body having a rear flat face and a front flat face, wherein the flat front face faces the outlet,

wherein the plunger body comprises at least two surrounding sealing lips, each sealing lip having a slot-shaped notch at least at one point, and which, as soon as the plunger is moved into the receptacle, permit a gas exchange of the receptacle interior with the outside atmosphere.

20. Receptacle according to claim 19 , containing a dental material.

21. Receptacle according to claim 20 , wherein the dental material is selected from pasty glasionomer cements, composites, or compomers.

22. A dental material dispensing assembly including:

a receptacle for pasty dental material, and

a plunger slideably disposable in the receptacle to forceably push the dental material out of the receptacle, said plunger including:

a plunger body with a flat forcer engaging face at a rear end thereof which in use is opposite a flat face at a front end thereof engageable with the dental material and wherein the front face of the plunger body largely corresponds with a face of an interior of the receptacle, and

at least two axially spaced sealing lips surrounding the plunger body and adapted in use to engage interior surface sections of the receptacle,

wherein each of said sealing lips have at least one slot shaped axially extending recess which in use permits gas exchange between the interior of the receptacle which in use contains the dental material and surrounding atmosphere.

23. A dispenser assembly according to claim 22 , wherein the dental material is selected from pasty glasionomer cements, composites, or compomers.

24. A dispenser assembly according to claim 22 , wherein the sealing lips each have two slot-shaped notches.

25. A dispenser assembly according to claim 24 , wherein the slot-shaped notch or notches of one sealing lip are arranged offset to the slot-shaped notch or notches of the other sealing lip.