Mixing and application capsule for producing a dental preparation

A mixing and application capsule for producing and discharging a dental preparation is disclosed. In order to prevent a liquid loss, a mixing and application capsule for producing a dental preparation is proposed according to the invention, which has: a capsule body (31) with a mixing chamber (32) for receiving a mixing component (41) and for mixing the dental preparation (43) from the mixing component (41) and a fluid (42) and with an outlet opening (33) for discharging the dental preparation (43), a first plunger body (11) which can be displaced in the capsule body (31), delimits the mixing chamber (32) in the capsule body (31) and has a channel (19) to guide the fluid (42) from a cavity (22) into the mixing chamber (32) and a projection (12), and a second plunger body (21) which can be displaced in the capsule body (31) relative to the first plunger body (11) and has the cavity (22) to receive the fluid (42), the cavity (22) being configured to receive the projection (12) of the first plunger body (11).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to German Application no. 10 2009 016 862.1, filed Apr. 8, 2009, which is incorporated herein by reference in its entirety.

BACKGROUND

The present invention relates to a mixing and application capsule for producing a dental preparation.

Mixing and application capsules allow a mixing of solid and fluid components in order, for example, to produce a dental preparation, which is then applied from the mixing and application capsule in the oral cavity of the patient. In order to produce glass ionomer cement, for example, a powder component is mixed with a liquid component. Various methods are known in the prior art to accommodate the liquid which is mixed on activation of the mixing and application capsule with the powdery component in order to produce the dental preparation.

The liquid is accommodated, for example, in a foil pouch, which is opened by bursting. The foil pouch is then squeezed out in order to press the liquid out of it and feed it to the powdery component. This method has the disadvantage that with a pouch which is very long in relation to the pouch diameter, in particular, the foil produces folds when being squeezed together, in which an indeterminate liquid residue remains. The result is that the dental preparation compound is mixed with too little fluid, so it does not have the desired properties. Therefore, either the size of the foil pouch and thus the liquid quantity are limited or else the dosage is imprecise. The diameter of the foil pouch cannot generally be varied as desired as the capsule would have to have a correspondingly larger diameter. A capsule with a larger diameter is, however, disadvantageous on application in the oral cavity of a patient. Also, the squeezing-out tongs used when squeezing out the mixing and application capsule are generally adapted for small capsule diameters.

A variation is that a foil pouch is arranged laterally on or at the capsule body. A pouch of this type may therefore have a significantly larger diameter and liquid quantity. However, the disadvantage exists that a separate activation tool is necessary to open the foil pouch and to bring its content in the capsule in contact with the powder (i.e. to activate the capsule). Also, proportionally more liquid remains in a pouch with a large diameter.

A further example of accommodating a liquid in a mixing and application capsule for producing a dental preparation is described in U.S. Pat. No. 6,386,872 B1. Arranged in the interior of the capsule body are a first and a second plunger, in the intermediate space of which a liquid is arranged. The first plunger delimits the mixing chamber in the interior of the plunger body, in which the powdery component is arranged. The plunger wall between the mixing chamber and liquid chamber has a desired breaking point. If the second plunger is pushed in the direction of the mixing chamber, a projection of the second plunger breaks through the desired breaking point of the wall of the first plunger, so the liquid flows into the mixing chamber in order to be mixed there with the powdery component. After the activation, for example in that the capsule is pressed by hand onto a table surface, the capsule has to be clamped into a mixing apparatus, which mixes the powder and liquid to form a paste by means of shaking movements.

The capsule is then clamped in squeezing-out tongs, with the aid of which the two plungers are moved further forward. The paste is discharged in the process through the cannula and, for example, used to fill a cavity of a tooth to be treated.

The arrangement according to U.S. Pat. No. 6,386,872 B1 has the disadvantage that diffusion losses of the liquid exist and the mixing and application capsule is therefore not suitable to be stored over a relatively long time period. The seal between the first and the second plunger is a sliding seal. If the seal is selected to be smooth-running, so a displacement of the second plunger relative to the first plunger is possible manually, there is an insufficient seal and the liquid can evaporate between the first and second plunger. If the seal is selected to be so tight that evaporation of the liquid through the seal is virtually completely avoided, the second plunger can only be displaced relative to the first plunger with the application of a large force which requires special tools and is no longer possible manually. Furthermore, a similar problem of liquid evaporation exists for the seal between the first plunger and the capsule body. The powdery component in the mixing chamber is hygroscopic and therefore tends to absorb moisture entering through the seal between the first plunger and capsule body. This also impairs the long-term storability of the mixing and application capsule. In addition, the thin-walled desired breaking point region of the wall of the first plunger is easy for the liquid to penetrate. The powdery component can therefore not only absorb moisture from the liquid via the seal between the first plunger and capsule body, but also through the desired breaking point region of the wall of the first plunger.

Further examples, also with a sliding seal are to be found, for example, in EP 1 226 790 or also in JP 2001340356.

WO 03/028871 A1 discloses a mixing capsule for a two-component mixing with a cylindrical container part and a spray nozzle molded onto the end face. A plunger is axially displaceably guided in the container part. Provided in the end face of the plunger is an opening adjoined by a liquid receptacle with a burstable wall or membrane. When the capsule is not activated, the membrane seals the opening. The cavity between the end faces of the container part and the plunger forms a mixing chamber. A movable activating part is provided in the mixing chamber. The activating part can be displaced by means of an activating pin sealing the spray nozzle in the non-activated state. In the activated state of the capsule, the activating part is substantially completely received in the liquid receptacle.

SUMMARY OF THE INVENTION

The invention is based on the object of providing a mixing and application capsule which eliminates the above-mentioned disadvantages of the prior art.

According to the invention, the object is achieved by a mixing and application capsule for producing a dental preparation, the mixing and application capsule having:a capsule body with a mixing chamber for receiving a mixing component and for mixing the dental preparation from the mixing component and a fluid and with an outlet opening for discharging the dental preparation,a first plunger body which can be displaced in the capsule body, delimits the mixing chamber in the capsule body and has a channel to guide the fluid from a cavity into the mixing chamber and a projection, anda second plunger body which can be displaced in the capsule body relative to the first plunger body and has the cavity to receive the fluid, the cavity being configured to receive the projection of the first plunger body.

The invention is based on the idea that the first plunger body is a double plunger, the projection of the first plunger of the double plunger being configured to press out a content of the cavity and the delimitation to the mixing chamber being configured as a second plunger of the double plunger. The mixing and application capsule is preferably configured as a telescopic cylinder, the first plunger body being a first cylinder and the second plunger body being a second cylinder, the first cylinder being telescopically displaceable in the capsule body and the second cylinder being telescopically displaceable in the first cylinder. On activation of the mixing and application capsule, a relative movement is carried out between the first and second plunger body, the projection of the first plunger body acting as a ram and filling up the cavity of the second plunger body in such a way that its content is pressed out. Correspondingly, the projection of the first plunger body is preferably a ram, which is configured such that if the ram is introduced into the cavity a content located in the cavity is displaced and the cavity is emptied. It is further preferred for the positive shape of the projection of the first plunger body to correspond to the negative shape of the cavity receiving the liquid or for the negative shape of the cavity receiving the liquid to correspond to the positive shape of the projection of the first plunger body. When discharging the dental preparation, the end of the first plunger body delimiting the mixing chamber acts as a plunger to push out the mixed dental preparation from the capsule body. Accordingly, a preferred mixing and application capsule according to the invention has: a capsule body with a mixing chamber for receiving a mixing component and for mixing the dental preparation from the mixing component and a liquid and with an outlet opening for discharging the dental preparation, a liquid container with a cavity for receiving the liquid and a double plunger body, which is arranged between the mixing chamber and the liquid container, and a channel for guiding the liquid from the cavity into the mixing chamber, the double plunger body at the first end facing the liquid container being configured to push a liquid arranged in the cavity out of the cavity so the liquid is removed into the channel, and wherein the double plunger body at the second end facing the mixing chamber is configured to push a dental compound produced in the mixing chamber out of the outlet opening.

Owing to the configuration according to the invention of the mixing and application capsule, a particularly tight liquid barrier is achieved. The capsule according to the invention provides the advantage that the liquid, which is arranged in a cavity in the second plunger body, cannot evaporate through the seal between the first and second hollow body. A smooth-running manual displaceability of the second plunger body relative to the first plunger body is also ensured. The mixing and application capsule according to the invention also provides the advantage that the liquid is prevented from diffusing through the first plunger body and mixing with the component in the mixing chamber, as the side facing the powder is, for example, sealed with a barrier layer foil and is therefore not permeable.

A further advantage of the mixing and application capsule according to the invention is that the foil sealing the cavity tears open abruptly when opened depending on the embodiment, so the liquid is sprayed at a high speed into the powder component. Incomplete emptying of the liquid can thus be avoided.

A further advantage of the mixing and application capsule according to the invention is that the use of a deformable foil pouch can be dispensed with. As, on activation of the mixing and application capsule according to the invention, the projection of the first plunger body is received in the cavity of the second plunger body, the fluid is completely pressed out of the cavity. The mixing ratio can thus be adhered to very precisely. The liquid quantity is also less severely limited as the cavity in the second plunger body can be selected to be correspondingly deep.

A further advantage of the mixing and application capsule according to the invention is that no separate tool is required for activation as the activation takes place by applying a pressure to the second plunger body.

Furthermore, the handling of the mixing and application capsule is particularly simple as the two plunger bodies are displaced in one and the same direction within the mixing and application capsule according to the invention to activate the mixing and application capsule and then discharge the dental preparation. This advantage is achieved, in particular, in that the end of the first plunger body delimiting the mixing chamber, when the dental preparation is discharged, acts as a plunger to push the mixed dental preparation out of the capsule body.

The cavity is preferably configured to receive a liquid capsule. A liquid capsule is preferably a hermetically sealed body. A configuration of this type of the mixing and application capsule according to the invention is particularly advantageous as the components, capsule body, first and second plunger body can be configured identically for a large number of different liquid capsules. Different liquid capsules may have different liquids or different liquid quantities.

The second plunger body is preferably configured as a liquid capsule. This embodiment is particularly advantageous as capsule bodies and first plunger bodies can be configured as standard components thus enabling production which is advantageous in terms of time and cost. The second plunger body may be configured differently for different mixing purposes, i.e. it may, for example, have different liquids or different liquid quantities.

The liquid capsule is preferably sealed with a foil. The liquid capsule is particularly preferably hermetically sealed with an easily tearable foil. This is particularly advantageous to already allow an opening of the liquid capsule even with light pressure on the second plunger body.

The foil preferably has at least one layer, which is at least partly a metal layer. It is preferable if the foil is impermeable to gas. A central region of the foil preferably has a metal layer. The metal layer preferably consists of a hard, easily tearable aluminum. A radial region of the foil preferably has a metal layer. The foil is preferably sealably coated on at least one side. The sealing layer preferably has a heat-seal lacquer. These embodiments used in a combined manner or alternatively have the advantage that the foil is used as a liquid barrier in particular to a component in the mixing chamber. In particular, an evaporation through the foil can be particularly effectively avoided in this manner.

The liquid capsule preferably at least partly has metal. Metal is advantageously used as an evaporation and volatilization barrier for the liquid. It is therefore preferred for the liquid capsule to be manufactured at least partially from metal. Furthermore, the inner layer is preferably also sealably coated, for example with a heat-seal lacquer. Other barrier layer materials or multi-layer upper structures with at least one barrier layer are also conceivable. Depending on the liquid used, possible examples as barrier layers are polyvinyl alcohol, ceramic fillers or other materials, which the person skilled in the art will accordingly choose for the purpose.

The mixing and application capsule, in particular the first plunger body, has a resistor element for the controlled prevention of displacement of the first plunger body into the capsule body. The displacement of the first plunger body is preferably controlled in such a way that the displacement of the first plunger body is only possible when the projection of the first plunger body is introduced into the cavity of the second plunger body or is introduced so far into the cavity of the second plunger body that the cavity is emptied. The resistor element is preferably realized in that the external diameter of the plunger body is at least partially larger than the internal diameter of the capsule body. An arrangement of this type advantageously means that the first plunger body cannot be inserted into the capsule body unintentionally. It is preferred for the larger external diameter to be configured by at least one tab, the tab preferably projecting from the capsule body. It is also preferred for the tab to engage in an annular groove in the interior of the capsule body. The first capsule body preferably has a tab rim at the end which receives the second plunger body. The tab rim preferably has radially outwardly bent tabs, or radially outwardly projecting tabs and tabs oriented parallel to the longitudinal axis of the first plunger body. On activation of the mixing and application capsule according to the invention, by applying a first force, the second plunger body is pushed into the first plunger body. A second force is preferably necessary to bend the tab and release or allow the displaceability of the first plunger body, the second force preferably being greater than the first force. Particularly preferably, the capsule body has an annular notch, in order to receive the tab or the tabs. Particularly preferably, the second plunger body, at its end which projects from the capsule body, has an indentation, which receives the tab, so a displacement of the first plunger body is only released if the tab is latched in the indentation, i.e. the second plunger body is introduced, in particular completely, into the first plunger body. A mixing and application capsule according to the invention is particularly preferably configured according to the invention in such a way that the first plunger body is configured as a sleeve for receiving the second plunger body, the first plunger body has radially outwardly bent tabs projecting out of the capsule body at the end which receives the second plunger body, the second plunger body has an indentation, the indentation is configured as an annular gap, and the tabs and annular gap are configured as a pairing in such a way that the displacement of the first plunger body is not possible until the tab is arranged in the annular gap. It is advantageously thus ensured that the liquid in the cavity of the second plunger body is completely pushed out therefrom in a first step before the dental compound produced is discharged in a further step.

A further preferred configuration to prevent the unintentional displacement of the first plunger body during activation, i.e. during the pressing out of the liquid, is the provision of correspondingly expediently selected friction conditions.

The capsule body preferably has a venting device for removing a gas from the mixing chamber of the capsule body. A venting device of this type is preferably configured as a gas-permeable filter membrane, which is impermeable to the mixing component in the mixing chamber and is arranged in at least a part of the outer wall of the plunger body. A filter membrane of this type is described, for example, in US 2004/0104133 A1, the disclosed filter membrane of which is referred to here. It is furthermore preferred for the seal between the capsule body and first plunger body to have venting slots. The venting slots are preferably arranged on the outer surface of the first plunger body and interrupt an annular sealing element of the first plunger body. Such configurations are preferred as the air in the interior of the capsule body can be removed particularly rapidly, so entry of the liquid into the mixing chamber is facilitated. This slotted seal is preferably configured several times one behind the other, the slots being offset with respect to one another, so a type of labyrinth seal is produced.

The projection of the first plunger body is preferably configured to open the liquid capsule. It is preferred for the projection of the first plunger body to be configured to puncture, push open, cut open, break open, and/or punch open the foil. This embodiment of the mixing and application capsule according to the invention is advantageous as an opening of the liquid capsule and a pressing out of the liquid is achieved in one movement in the method step of pressing the second plunger body into the first plunger body.

The projection of the first plunger body preferably has means for punching out a region of the foil, which opposes the channel. By means of this embodiment of the mixing and application capsule according to the invention it is particularly advantageously achieved that only the relevant region of the foil for transferring the liquid from the cavity into the mixing chamber, namely that which opposes the channel, is opened. A loss of liquid in the radial direction is thus avoided.

A mixing and application capsule for producing a dental preparation is particularly preferred which has: a capsule body with a mixing chamber for receiving a mixing component and for mixing the dental preparation from the mixing component and a fluid and with an outlet opening for discharging the dental preparation, a first plunger body which can be displaced in the capsule body, delimits the mixing chamber in the capsule body and has a channel to guide the fluid from a cavity into the mixing chamber and a projection, and a second plunger body which can be displaced in the capsule body and has the cavity to receive the fluid, the cavity being configured to receive the projection of the first plunger body, wherein the mixing and application capsule also has a cannula pivoting element at the outlet opening for applying the dental preparation, the capsule body having a gas-permeable filter membrane and/or the seal between the capsule body and first plunger body having venting slots for removing a gas from the mixing chamber of the capsule body, the second plunger body being configured as a liquid capsule and the liquid capsule being sealed with an aluminum foil, the aluminum foil being sealably coated on at least one side, the first plunger body having at least one tab rim with radially outwardly bent tabs projecting out of the capsule body and the second plunger body having an indentation at its end projecting out of the capsule body, the indentation being configured to receive the bent tabs, the first plunger body having an edge recess, which is configured to receive an edge projection of the second plunger body, and wherein the projection of the first plunger body has pins for punching out a region of the foil, which opposes the channel.

As an alternative to the cannula pivoting element shown here, another opening mechanism is conceivable, for example, as described, for example, in DE19906887C1.

The projection of the first plunger body preferably has a blade for cutting open the foil, the blade being arranged along the periphery of the projection. The projection of the first plunger body preferably has elevations extending radially from the channel to the blade to assist the outflow of the liquid into the channel. Such configurations of the mixing and application capsule according to the invention offer the advantage that a long region of the foil is simultaneously cut open and the liquid can be rapidly removed from the cavity through the channel. The risk of a loss of liquid is thus avoided.

A mixing and application capsule according to the invention for producing a dental preparation is particularly preferred which has: a capsule body with a mixing chamber for receiving a mixing component and for mixing the dental preparation from the mixing component and a fluid and with an outlet opening for discharging the dental preparation, a first plunger body which can be displaced in the capsule body, delimits the mixing chamber in the capsule body and has a channel to guide the fluid from a cavity into the mixing chamber and a projection, and a second plunger body which can be displaced in the capsule body and has the cavity to receive the fluid, the cavity being configured to receive the projection of the first plunger body, wherein the mixing and application capsule also has a cannula pivoting element at the outlet opening for applying the dental preparation, the capsule body having a gas-permeable filter membrane and/or the seal between the capsule body and first plunger body having venting slots for removing a gas from the mixing chamber of the capsule body, the second plunger body being configured as a liquid capsule and the liquid capsule being sealed with an aluminum foil, the aluminum foil being sealably coated on at least one side, the first plunger body having at least one tab rim with radially outwardly bent tabs projecting out of the capsule body and the second plunger body having an indentation at its end projecting out of the capsule body, the indentation being configured to receive the bent tabs, the first plunger body having an edge recess, which is configured to receive an edge projection of the second plunger body, and wherein the projection of the first plunger body has a blade for cutting open the foil and elevations extending radially from the channel to the blade, the blade being arranged along the periphery of the projection.

The second plunger body preferably has a projection in order to open the liquid capsule. The projection of the second plunger body is preferably conical. The projection of the second plunger body is preferably configured to puncture, push open, cut open, break open and/or punch open the foil. The projection of the first plunger body and the projection of the second plunger body are preferably configured to open the foil by the action of force on both sides. An arrangement of this type provides the advantage that the liquid capsule is opened in the direction in which the liquid has to flow in order to enter the mixing chamber. Owing to the movement of the projection of the second plunger body in the direction of the mixing chamber, the movement of the fluid is correspondingly initiated, whereby liquid losses are further avoided.

A further advantage of this configuration is that the liquid channel of the first plunger body on complete displacement of the second plunger body is filled by the projection of the second plunger body and the liquid quantity possibly remaining in the liquid channel is significantly reduced.

It is to be regarded as a further advantage that the liquid channel, from this aspect, may have larger dimensions without the liquid quantity remaining in the channel being increased. This, in particular, provides advantages if the first plunger is produced as an injection-molded part, because very small and, in relation to the diameter, very long channels, bring about premature tool wear. The process reliability in the production of the first plunger body is correspondingly higher.

The projection of the first and/or second plunger body is preferably configured to open the liquid capsule, in particular to puncture it. If projections of both the first and the second plunger body are used to open the liquid capsule, this provides the advantage that a particularly reliable and rapid opening is made possible and a particularly rapid outflow of the liquid through the channel into the mixing chamber can be achieved. Liquid losses in the radial direction can thus be avoided. Furthermore, with a puncturing of the liquid capsule, a very targeted opening process is achieved, so it can be established very precisely by the producer where the liquid capsule is to be punctured to ensure a rapid and loss-free outflow of the liquid into the mixing chamber.

The channel is preferably configured to receive the projection of the second plunger body. An arrangement of this type is particularly advantageous as the projection of the second plunger body, by introduction into the channel, ensures that no liquid residues remain in the channel. A precise mixing ratio of the fluid and component in the mixing chamber can thus be better adjusted. Furthermore, a simple manufacturing of the first plunger body by the injection-molding method is made possible as the channel is already inserted during the injection-molding production and does not have to be drilled in retrospectively.

A mixing and application capsule according to the invention for producing a dental preparation is particularly preferred which has: a capsule body with a mixing chamber for receiving a mixing component and for mixing the dental preparation from the mixing component and a fluid and with an outlet opening for discharging the dental preparation, a first plunger body which can be displaced in the capsule body, delimits the mixing chamber in the capsule body and has a channel to guide the fluid from a cavity into the mixing chamber and a projection, and a second plunger body which can be displaced in the capsule body and has the cavity to receive the fluid, the cavity being configured to receive the projection of the first plunger body, wherein the mixing and application capsule also has a cannula pivoting element at the outlet opening for applying the dental preparation, the capsule body having a gas-permeable filter membrane and/or the seal between the capsule body and first plunger body having venting slots for removing a gas from the mixing chamber of the capsule body, the second plunger body being configured as a liquid capsule and the liquid capsule being sealed with an aluminum foil, the aluminum foil being sealably coated on at least one side, the first plunger body having at least one tab rim with radially outwardly bent tabs projecting out of the capsule body and the second plunger body having an indentation at its end projecting out of the capsule body, the indentation being configured to receive the bent tabs, wherein the first plunger body has an edge recess configured to receive an edge projection of the second plunger body, wherein the second plunger body has a conical projection in order to puncture, push open, cut open, break open, and/or punch open the liquid capsule, and the channel being configured to receive the conical projection of the second plunger body. It is particularly preferred in this embodiment that the projection of the first plunger body and the projection of the second plunger body are configured and cooperate with one another to open the foil by the action of force on both sides.

The first plunger body preferably has an edge recess, which is configured to receive an edge projection of the second plunger body. The edge recess is preferably configured to guide the edge projection. The edge recess and edge projection preferably form a seal between the cavity and an outer region of the mixing and application capsule. An embodiment of this type of the mixing and application capsule according to the invention provides the advantage that a volatilization of the fluid in the edge regions of the first and second plunger body can be further reduced. Furthermore, this provides the advantage that mechanical guidance of the second plunger body is provided during the introduction into the first plunger body.

The second plunger body preferably has a peripheral projection, which is configured as a protrusion, and which, on the one hand, is used as a seal between the first and second plunger and, on the other hand, together with a shoulder, in particular in the interior of the first plunger body, means that the second plunger body does not unintentionally slide out during storage and transportation.

A mixing and application capsule according to the invention for producing a dental preparation is particularly preferred, which has: a capsule body with a mixing chamber for receiving a mixing component and for mixing the dental preparation from the mixing component and a fluid and with an outlet opening for discharging the dental preparation, a first plunger body which can be displaced in the capsule body, delimits the mixing chamber in the capsule body and has a channel to guide the fluid from a cavity into the mixing chamber and a projection, and a second plunger body which can be displaced in the capsule body and has the cavity to receive the fluid, the cavity being configured to receive the projection of the first plunger body, wherein the mixing and application capsule also has a cannula pivoting element at the outlet opening for applying the dental preparation, the capsule body having a gas-permeable filter membrane and/or the seal between the capsule body and first plunger body having venting slots for removing a gas from the mixing chamber of the capsule body, the second plunger body having a liquid capsule and the liquid capsule being sealed with an aluminum foil, the aluminum foil being sealably coated on at least one side, the first plunger body having at least one tab rim with radially outwardly bent tabs projecting out of the capsule body and the second plunger body having an indentation at its end projecting out of the capsule body, the indentation being configured to receive the bent tabs, the first plunger body having an edge recess, which is configured to receive an edge projection of the second plunger body, and wherein the projection of the first plunger body is convex or rounded or hemispherical and the base of the liquid capsule, i.e. the wall of the liquid capsule opposing the foil, is concave or rounded or hemispherical.

It is further preferred that the capsule body, first, second plunger body and/or the liquid capsule are cylindrical. It is particularly preferred for their elements, in particular recesses, projections, cavity, liquid capsule, resistor element, venting device, means for punching out and/or blade, as described above in detail are configured and/or arranged rotationally symmetrically.

The channel is preferably arranged parallel to the longitudinal axis of the first plunger body. The channel is preferably also arranged in the centre of the first plunger body. It is further preferred for the channel to be arranged in an edge region of the first plunger body. It is particularly preferred for the channel to have means for preventing discharge of the mixing component. A means of this type is preferably arranged at the end of the channel facing the mixing chamber. The means is also preferably a tapering in the interior of the channel.

It is also preferred for the mixing and application capsule according to the invention to have a cannula pivoting element, which is coupled to the outlet opening, in order to apply the dental preparation.

The channel preferably has means to prevent the mixing component from the mixing chamber entering the channel. These means particularly preferably prevent undesired entry of the mixing component into the channel. It is furthermore preferred that a means of this type is arranged between the first plunger body and the capsule body, for example as a foil, which separates the mixing chamber from the first capsule body. It is preferred in particular for the means for preventing the entry of the mixing component from the mixing chamber into the channel to be a check valve, a flexible check flap, a porous structure, a narrow gap and/or a membrane which can be torn open. With a configuration of this type it is advantageously achieved that the first mixing component, in particular the powder component, remains in the mixing chamber until activation by mixing with the fluid, or is protected from outer influences, and the desired mixing ratio determined by the producer coincides as well as possible with the actual mixing ratio in fact achieved in the mixing chamber.

The outlet opening preferably has a cannula, which has means on its inside for arranging an extension. It is preferred, in particular, for the outlet opening and/or the cannula to have means which allow an attachment of a thin extension, in particular. The cannula is preferably straight or (optionally partially) bent. It is preferred for the cannula to have, on its inside, devices which allow the attachment or insertion of a separate very thin extension. This extension may, for example, latch in non-detachably by means of a snap-on mechanism or be held by friction. Such extensions are used, for example, for root canal fillings, but tend to be a hindrance during activation or mixing, because they are mechanically sensitive. For this reason, it is recommended to attach an extension of this type only after mixing.

The outlet opening of a mixing and application capsule according to the invention is preferably configured for connection to a cannula (or another device for discharging the dental preparation), i.e. it does not have a cannula. A modular construction of this type is advantageous as the cannula (and optionally the thin extension) can be selected individually depending on the purpose and site of use.

DETAILED DESCRIPTION

FIG. 1illustrates an embodiment of a mixing and application capsule for producing a dental preparation43with a capsule body31, a first plunger body11configured as a passage plunger and a second plunger body21configured as a liquid container. The capsule body31is substantially cylindrical and has, at its first end, a cap34, on which a cannula33is rotatably arranged by means of an articulated joint35. The cannula joint arrangement33,35is preferably configured as a cannula pivoting element. In a first position (as shown inFIGS. 1 and 2ato2c), the cap34and the cannula33are rotated by means of the articulated joint35in such a way that the inside of the cannula33is not connected to the mixing chamber32of the capsule body31. In a second position, the cap34and cannula33are arranged by means of the articulated joint35(as explained below with reference toFIG. 2d) in such a way that the dental compound43mixed in the interior of the capsule body31can be discharged through the cannula33.

Arranged in the interior of the capsule body31is the mixing chamber32, which is configured as a cavity and, in the filled state of the mixing and application capsule, has a powdery component41, which, mixed with liquid42, forms the dental preparation43. The mixing chamber32is delimited at the first end of the capsule body31by the cap and cannula arrangement33,34and, at the second end, configured to be open, of the capsule body31is delimited by the passage plunger11. Moreover, the component41may not only be powdery, but instead may also be paste-like, liquid or fluid.

The passage plunger11is displaceably arranged along the longitudinal axis of the capsule body31. It is used for pressing out the dental compound produced in the mixing chamber32through the cannula33. The passage plunger11has a channel19for guiding a fluid42, which is configured as a through-channel. A fluid in the sense of this application is a substance, which does not oppose a sheer stress however small with any resistance, as applies, in particular, to gases and liquids. In the embodiment shown inFIG. 1, the through-channel19is configured along the central longitudinal axis of the passage plunger11. The through-channel19forms the connection between the mixing chamber32and the second plunger body21, which has a cavity22to receive the fluid42. The through-channel19is configured to prevent the powdery component42entering the channel or passing through it. The channel19may have corresponding means or be configured correspondingly narrow.

Such means for preventing powder entering the channel may, for example, be a sponge-like, porous mass or a check flap or a check valve or a thin membrane, which tears open during activation.

The second plunger body configured as a liquid container21is arranged on the side of the passage plunger11remote from the mixing chamber32. The liquid container21has an, in particular, sealable or sealably coated cavity22, in which the liquid42is arranged, which is used for mixing the dental preparation43in combination with the powdery component41. The cavity22of the liquid container21is hermetically sealed by a foil23. The foil23is preferably an aluminum foil, which is sealably coated on at least one side. The sealing layer preferably consists of a heat-sealing lacquer, but may also be a laminate layer.

The passage plunger11has a projection12as a ram, which, with regard to the form and/or the volume corresponds to the cavity22. The projection12has at least one pin13, which is used to cut open or punch out the foil23of the liquid container21.

The cavity22of the liquid container21is delimited laterally by a radial projection or edge projection24, which forms the edge region of the liquid container21and the side wall of the cavity22. The edge projection24is used to guide the liquid container21during displacement along the longitudinal axis of the capsule body31and is received in a correspondingly formed edge recess14in the edge region of the passage plunger11.

A liquid loss from the liquid container21is avoided according to the invention as three sides of the liquid container21are so thick-walled that a liquid loss through the walls does not occur. A liquid loss through the relatively thin-walled foil23is prevented by the foil23being manufactured at least partially from metal. In the case, a layer of the foil23is, for example, configured as a metal layer and/or specific regions of the foil23have a metal fraction. The liquid42may, according to the invention, be stored in this manner over a long time period in the cavity22, without risking evaporation of the liquid or other volatilization.

Since virtually no liquid can escape from the cavity22, the purity of hygroscopic powder41in the mixing chamber32also remains guaranteed over a long time period. A mixing and application capsule is generally stored in a hermetically sealed receptacle, such as a blister or a tubular pouch. According to the invention, a long storability of the mixing and application capsule is achieved.

The dental preparation43mixed from the powdery and the liquid component41,42has properties which are precisely adjusted by the producer, as virtually no liquid residues remain in the cavity22when the cavity22is pushed over the projection12. As no sliding seal delimits the fluid42of the mixing and application capsule according to the invention, a liquid loss via a seal of this type can also be avoided and the sliding seals between the liquid container21and passage plunger11and between the passage plunger11and capsule body31can be configured to be correspondingly smooth-running as they are only used at the moment of activation and therefore are not in contact with liquid during storage. It is possible to activate the capsule with a low application of force.

It is also possible to accommodate a large liquid quantity in a liquid container21, which in a case such as this is configured correspondingly long (and analogously with this, the projection12of the passage plunger11), without the diameter of the mixing and application capsule having to be enlarged, which would lead to a non-manageability during application in the oral cavity of the patient. As the activation and the discharge of the dental preparation43takes place by the application of force in only one direction, i.e. along the longitudinal axis of the mixing and application capsule, the use of the mixing and application capsule according to the invention is possible with the aid of only one tool and in a particularly simple manner and in a short time.

The operation of the mixing and application capsule according to the embodiment shown inFIG. 1by activation and discharge of the dental preparation is shown inFIGS. 2ato2d. The mixing and application capsule ofFIGS. 2ato2dhas the capsule body31, the passage plunger11and the liquid container21. A liquid42is arranged in the cavity22of the liquid container21, the cavity22being sealed by a foil23. The powder41is arranged in the mixing chamber32of the capsule body31, which is delimited, on the one hand, by the flap and cannula arrangement33,34and, on the other hand, the passage plunger11.

The operation of the mixing and application capsule according to the invention will now be described starting withFIG. 2a.FIG. 2ashows the starting situation described above. In a first method step (FIG. 2b), pressure is exerted on the liquid container21in the direction of the passage plunger11along the longitudinal axis of the capsule body31. By bringing pins13of the projection12of the passage plunger11into contact with the foil23of the liquid container21, the pins13pierce the foil23and, on further displacement of the liquid container21, punch out a part region of the foil23. The liquid cavity22is opened. As the pins13are arranged close to the through-channel19, the liquid42flows off directly through the through-channel19into the mixing chamber32of the plunger body31.

By further displacement of the liquid container21in the direction of the passage plunger11, the projection12of the passage plunger11is introduced into the cavity22of the liquid container21, it displaces the liquid42out of the cavity22and pushes it into the through-channel19and the mixing chamber32of the capsule body31. Since the liquid container21is laterally delimited by the edge region24, which is introduced in recesses19in the passage plunger11, a liquid loss in the edge region and via the seal between the passage plunger11and the liquid container5can be avoided. It is of assistance here that the single escape possibility for the air located in the edge recess14is provided through the channel19and this air entrains the liquid42with it. The air thus introduced into the mixing chamber and the air, which is displaced by the entering liquid42escape through the venting devices of the first plunger and/or the venting device of the capsule body.

If the projection12is completely introduced into the cavity22, in which the liquid42was situated in the starting position, the first method step ends. The liquid quantity provided by the producer is now located in the mixing chamber32of the capsule body31. The mixing then takes place in a mixing apparatus. These mixing apparatuses are generally conventional in the dental practice and give the capsule an intense shaking movement, which is frequently directed substantially parallel to the longitudinal axis of the capsule. The capsule is clamped for this purpose in a receiving fork and held tight by a spring force. The clamping points are the cap34and liquid container21. This means that, in each case, in the reversing position of the shaking movement, in each case, apart from the spring force of the receiving fork, an acceleration force also acts on the liquid container21and any incomplete liquid emptying during mixing is further improved. Depending on the type of receiving fork and the mixing apparatus, it is moreover possible for the activation to take place during the clamping and/or during the mixing. Manual activation can in this case be dispensed with.

The next method step for using the mixing and application capsule if used to discharge the mixed paste43(FIG. 2d). For this purpose, the articulated joint35is brought into the second position, so the cannula33forms a connection between the mixing chamber32and outer region of the mixing and application capsule. By exerting further pressure on the liquid container21, the liquid container21, and simultaneously the passage plunger11, are displaced in the direction of the mixing chamber32and the volume thereof is reduced. Simultaneously, the mixing chamber32is further vented by means of the venting device of the capsule body31or passage plunger11if the air does not discharge from the cannula. The mixed paste43is then discharged through the cannula33and can be applied.

FIG. 3ashows a detailed view of the region C ofFIG. 1, in which the region between the liquid container21, passage plunger11and capsule body31is shown. The notch36is used here to receive a radially outwardly bent tab17abetween the capsule body31and passage plunger11, as will be described below. As is shown inFIG. 3a, the liquid container21has a protrusion26, which strikes against a step of the interior of the passage plunger11in such a way that the liquid container21is prevented from sliding out of the passage plunger11. Furthermore, the step and protrusion arrangement can be used to prevent a discharge of liquid when the foil23is opened and the liquid flows out of the cavity22.

FIG. 3bshows a semi-cut-open detailed view of the passage plunger11. The passage plunger11according to the embodiment shown inFIG. 1has a through-channel19, which is located in the centre of the projection12. Furthermore, two or four pins13are shown inFIG. 3b, which are used to punch out a central region of the foil23of the liquid container21.FIG. 3balso shows a tab rim, which is used as a resistor element in order to ensure the two-step operation described in regard toFIGS. 2ato2d, i.e. the activation and discharge. The tab rim has radially outwardly bent tabs17aand tabs17bconfigured parallel to the longitudinal axis of the passage plunger11.

FIGS. 3cto3eshow further detailed views of the passage plunger11ofFIG. 1according to the axes shown.

FIG. 4shows a further embodiment of the mixing and application capsule according to the invention. Statements and descriptions for components, which have already been described above with the same reference numerals, apply analogously below.

The embodiment shown inFIG. 4differs from the embodiment ofFIG. 1by the configuration of the passage plunger11and liquid container21. The liquid container21has, in its interior, a projection, which is configured as a pin25. The pin25, with regard to the configuration and/or volume, substantially corresponds to the through-channel19of the passage plunger11. The through-channel19of the passage plunger11is conical in the embodiment ofFIG. 4in order to receive the pin22. Other cross sections, such as, for example, pyramid-shaped, cylindrical or star-shaped are also possible.

FIGS. 5ato5dshow the activation of the mixing and application capsule ofFIG. 4and the discharge of the mixed paste43through the cannula33. In this case, the sequence inFIGS. 5ato5ddiffers from that ofFIGS. 2ato2dwith regard to the activation of the mixing and application capsule. InFIG. 5a, the starting state is shown, in which a powder41is arranged in the mixing chamber of the plunger body31, which has the passage plunger11in its interior, and the liquid container21is arranged on the side of the passage plunger11remote from the mixing chamber32. The cavity22of the liquid container21has liquid42and is sealed with a foil23. The pin25is arranged in the interior of the cavity22of the liquid container21. By the application of force on the liquid container21, the latter is pushed onto the passage plunger11. The projection12of the passage plunger11acts as a resistance here, which opposes the foil23of the liquid container21and dents it in the centre in the direction of the cavity.

By exerting further pressure on the liquid container21, the pin25opens or perforates the foil23in the region of the through-channel19, as shown inFIG. 5b. The liquid can now discharge from the cavity22through the through-channel19. By further insertion of the liquid container21into the passage plunger11, the cavity22is taken up by the projection12, so the cavity22is emptied of liquid. The pin25pushes the liquid through the through-channel19into the mixing chamber32. A mixing of the powder41and the liquid42takes place in the mixing chamber32, as described above, for example in a mixing apparatus and the mixed paste43can be discharged from the mixing and application capsule. Instead of powder41, a liquid or pasty substance may alternatively be located in the mixing chamber32in this or another embodiment and is mixed with the liquid42with or without the aid of a mixing apparatus.

FIG. 6shows a further embodiment of the mixing and application capsule according to the invention. The embodiment ofFIG. 6differs from those ofFIGS. 1 and 4with regard to the configuration of the passage plunger11and the liquid container21. The liquid container21of the embodiment ofFIG. 6is configured to receive a liquid capsule50. The interior of the liquid capsule50is preferably coated with sealing lacquer. In the embodiments ofFIGS. 1,4and9, the cavity22is configured as a liquid capsule integrated with the liquid container21. It is, however, also possible for the embodiments ofFIGS. 1,4and9to be equipped or operated with a separate liquid capsule50. The liquid capsule50is hermetically sealed with a foil23relative to the projection12of the passage plunger11. The liquid capsule50may consist here, for example, of a barrier material, such as, for example, aluminum, and has, on its inside, a sealable layer. Liquid losses through diffusion are completely ruled out in this embodiment (in particular virtually). The projection12of the passage plunger11is configured according to the embodiment ofFIG. 6with a round, convex hemispherical surface, so the opening of the foil23does not take place by means of a punching out or cutting open but by means of pushing open.

The advantage of the separate metallic liquid capsule is: the liquid capsule50can be produced economically by the deep-drawing method, whereas the container21with its comparatively complex geometry can be produced as an injection-molded part.

Compared with the prior art, as described, for example, in DE 3920537A1, the advantage is produced here that the liquid capsule50does not have to be deformed to empty the liquid, so it can have a substantially higher wall thickness and therefore can be deep-drawn substantially deeper in relation to the diameter. Furthermore, because of the deformation of the thick wall thickness of the liquid capsule50, which does not take place during the activation, no folds can form, in which an unspecific quantity of liquid would remain.

The activation of the mixing and application capsule of the embodiment ofFIG. 6and the discharge of the mixed paste43is shown inFIGS. 7ato7d. In starting stage, the capsule body31, passage plunger11and liquid container21with the liquid capsule50are in an arrangement as shown inFIG. 7a. The liquid42is arranged in the liquid capsule50and the powder41is arranged in the mixing chamber of the capsule body31. By applying force onto the liquid container21, the projection12of the passage plunger11breaks through the thin foil23and the liquid of the cavity22obtains access to the through-channel19. The liquid runs the through the through-channel19and blends with the powder41in the mixing chamber32. The projection12is completely pushed into the liquid capsule50, so liquid residues from the cavity22of the liquid capsule50are pushed through to the concave hemispherically formed base thereof and pressed into the mixing chamber32. After mixing the liquid42with the powder41, pressure is exerted on the liquid container21and the passage plunger11, so the mixed paste43discharges through the cannula33.

FIG. 8ais a detailed view of the region C ofFIG. 6. Similarly to as shown inFIG. 3a, the liquid container21has an outer radial projection as a protrusion26, which engages with a step of the passage plunger11to avoid the liquid container21sliding out and to achieve an additional sealing with respect to the edge recess14. Also as inFIG. 3a, the capsule body31has an annular notch36to receive a resistor element17a. It is also shown inFIG. 8athat the liquid capsule50, which delimits the cavity22, is inserted into the liquid container21.

FIG. 8bshows a semi cut-open detailed view of the passage plunger11of the embodiment ofFIG. 6. The projection12is provided here with a round, hemispherical surface, the through-channel19being arranged in the centre of the projection12along the longitudinal axis thereof.FIGS. 8cto8eshow further detailed views of the passage plunger11ofFIG. 6according to the axes shown.

FIG. 9shows a further embodiment of the mixing and application capsule according to the invention. The embodiment ofFIG. 9differs from those ofFIGS. 1,4and6with respect to the configuration of the passage plunger11and the liquid container21. The projection12of the passage plunger11is cylindrical and has a blade15which extends along the periphery of the projection surface. Arranged on the surface of the projection12facing the foil23are also elevations16, which extend in the radial direction between the through-channel19and blade15.

The liquid container21is configured with a cylindrical cavity22, which has recesses to receive the blade15and the elevations16. The liquid container21is ram-like, i.e. configured with a corresponding profiling in order to receive the projection12, blade15and elevations16in such a way that virtually no cavities remain between the passage plunger11and liquid container21, in which liquid residues could remain.

The operation of the mixing and application capsule ofFIG. 9according to the invention is shown inFIGS. 10ato10d. The starting situation is shown inFIG. 10a, in which the capsule body31has a mixing chamber32with powder41, the liquid container21has a liquid42and the passage plunger11is arranged between the mixing chamber32and liquid container21. To activate the mixing and application capsule, the liquid container21is displaced in the direction of the passage plunger11, so the blade15separates the foil23at its edge region and allows the liquid to flow away out of the cavity22into the through-channel19(FIG. 10b). In order to avoid the foil23sealing the hole of the through-channel19for the liquid42, the liquid container21has channels at its inner surface, through which the liquid42can flow away, even if the foil23is placed on its surface. The channels of the liquid container21in this case correspond substantially to the elevations16of the surface of the projection12of the passage plunger11.

By further action of force on the liquid container21in the direction of the passage plunger11, the cavity22is completely emptied of liquid and the liquid is pressed into the mixing chamber32to blend with the powder41(FIG. 10c). The dental preparation43is produced by mixing the powder41and the liquid42and through a further action of force on the liquid container21and the passage plunger11pushed out through the cannula33as a mixed paste43(FIG. 10d).

FIG. 11ashows a detailed view of the region C ofFIG. 9. Shown in this detailed view is the projection12of the passage plunger11, which has a radial peripheral blade15. Proceeding from the hole of the through-channel19up to the blade15, elevations16are arranged in the radial direction of the projection12.

FIG. 11bshows a semi-cut open detailed view of the passage plunger11of the embodiment ofFIG. 9. The passage plunger11has a cylindrical projection12, in the interior of which is arranged the through-channel19. Arranged on the surface of the projection12facing the liquid container21is an annular blade15. The blade15is preferably funnel-shaped to assist a targeted discharge of the liquid42. Arranged between the blade15and the through-channel19in the radial direction are elevations16for removing the liquid. Furthermore, the elevations16, in combination with the corresponding channels on the inner surface of the liquid container21prevent the foil23from sealing the through-channel19.FIGS. 11cto11eshow further detailed views of the passage plunger11ofFIG. 9according to the axes shown. Instead of the elevations drawn, indentations or channels are alternatively conceivable, which are used for the same purpose.

Furthermore,FIG. 11cshows a protrusion18with venting slots37. This arrangement is implemented twice one behind the other in this example, the venting slots37not being aligned with one another and therefore forming a labyrinth seal.

FIG. 12shows an outer view of the mixing and application capsule according to the invention. The capsule body31is shown, on the first end of which the cap34is located. The second end of the capsule body31is configured open to receive the passage plunger11and the liquid container21. The passage plunger11, as described above, has tabs17bwhich are oriented parallel to the longitudinal axis, i.e. straight, and bent tabs17a, which only allow a displacement of the passage plunger11in the direction of the mixing chamber32if a predetermined force acts on the passage plunger11or the liquid container21. The straight tabs17bcan be seen inFIG. 12, whereas the bent tabs17aare not shown as they engage in the annular notch36of the capsule body. The bent tabs17amean that upon an action of force on the liquid container21along the longitudinal axis of the mixing and application capsule, the liquid container21, in a first step, is pushed onto the passage plunger11, without the passage plunger11being pushed into the mixing chamber32, and in that, in a second step, in which the liquid42is already pressed out of the cavity22by introducing the projection12, the passage plunger11moves into the mixing chamber32. The straight tabs17bare used for better guidance of the liquid plunger21and prevent it from undesired tilting.

FIG. 13shows a detailed view of the region B ofFIG. 9between the capsule body31and the passage plunger11. The passage plunger11has a protrusion18, which is used for sealing between the mixing chamber32and the outer region of the mixing and application capsule. The protrusion18has venting slots37, which allow a pressure compensation to be provided upon a telescoping of the telescopic cylinder between the mixing chamber32and outer region of the mixing and application capsule. The passage plunger11optionally has a plurality of radially arranged protrusions18, which are in each case interrupted by venting slots37, so a venting labyrinth is produced, which is easy for gas to penetrate, but not for the powder or fluid and the dental compound produced.

In addition or alternatively, the mixing and application capsule according to the invention has a gas-permeable membrane, for example in the cap region34, through which a venting of the mixing chamber32takes place on insertion of the liquid plunger21into the passage plunger11and insertion of the passage plunger11into the mixing chamber32. The gas-permeable membrane is, in this case, impermeable to the powdery component41, the fluid42and the mixed dental preparation compound43.

Venting devices such as the venting slot37and/or the venting membrane mean that the pressure built up by activating the mixing and application capsule in the mixing chamber32can rapidly be relieved, so it is made easier for the liquid42to flow into the mixing chamber32. Furthermore, the exertion of force to insert the liquid container21and the passage plunger11is simultaneously reduced. By rapidly removing the air from the interior of the capsule body31both in the mixing chamber32and in the cavity between the passage plunger11and liquid container21it is achieved that the liquid42is not, in particular, distributed in the region between the passage plunger11and liquid container21. This intermediate space remains dry, even if the foil23is not opened in its central region but in a radial region.

FIG. 14ashows a cross section of a mixing and application capsule according to the invention, with the aid of which the operation of the tabs17abent outward is explained. A mixing and application capsule according to the invention has, as is explained above, a capsule body31, a passage plunger11and a liquid container21. The cap and cannula arrangement33,34is used to discharge the dental preparation43produced. The region between the capsule body31, passage plunger11and liquid container21is shown in detail inFIG. 14b.

With the arrangement shown inFIG. 14bof the resistor elements17aarranged projecting radially outwardly, the passage plunger11is prevented during the activation process of being displaced unintentionally into the mixing chamber32even if the liquid42in the cavity22has not yet been completely pressed out. A plurality of outwardly bent tabs17aare arranged at the rear end of the passage plunger11, i.e. at that end of the passage plunger11which is remote from the mixing chamber32. The straight tabs17b, which are oriented parallel to the longitudinal axis of passage plunger11, are used, in particular, to guide the passage plunger11inside the capsule body31.

If the liquid container21is displaced in the direction of the passage plunger11, the outwardly bent tabs17ahinder the passage plunger11from entering further into the capsule body31. It is achieved, by means of the outwardly bent tabs17a, that the external diameter of the passage plunger11is at least partially larger than the internal diameter of the plunger body31. In the embodiment shown inFIGS. 14ato14cand15ato15c, the bent tabs17aproject into the outer area of the mixing and application capsule. However, an annular groove may optionally be arranged in the interior of the capsule body31, in which the bent tabs17aengage in the same manner as is illustrated inFIG. 14bat the outer region of the plunger body31.

The bent tabs17ain the indentation27of the liquid container21only obtain space to release the movement of the passage plunger11into the mixing chamber32when the liquid container21has been inserted completely into the passage plunger11. The indentation27is preferably configured as a reduced diameter at the rear end of the liquid container21. In this case, the arrangement of the indentation27on the liquid container21corresponds to the state when the projection12has emptied the cavity22. The straight tabs17bare used both to guide the passage plunger11inside the capsule body31and also to guide the liquid container21inside the passage plunger11.

According to the invention, further embodiments are provided, in which the through-channel19is arranged parallel to the longitudinal axis of the passage plunger11. It is also possible to configure the through-channel19in another orientation inside the passage plunger11in order to transfer the liquid42from the cavity22into the mixing chamber32of the capsule body31. Other geometric configurations of the projection12than those shown in the figures, and in a corresponding manner, of the cavity22, are conceivable, such as, for example, pyramid-shaped, cylindrical, conical forms. The opening of the foil23preferably takes place by punching out, pushing open, cutting open or other opening mechanisms, which are based on the pressure effect on the liquid container21relative to the passage plunger11. An opening of the foil23may take place in the centre or else in the edge regions. It is optional for the embodiments ofFIGS. 1,4and9to have a liquid capsule50or for the liquid container21ofFIG. 6to be used without a separate liquid capsule50.