UNIT DOSE PACKAGE

Abstract

A unit dose package for a dental composition, comprising: (a) a rigid support member having a proximal end and a distal end, the rigid support member supporting one or more storage compartments for the dental composition and providing fluid flow communication between the one or more storage compartments and one or more discharge orifices, wherein the one or more storage compartments each have a volume of 10 l to 1000 l, and (b) a discharge conduit having a longitudinal axis extending from a proximal end to a distal end, the discharge conduit being rotatably attached to the distal end of the rigid support member for rotation around its longitudinal axis, wherein the attachment of the discharge conduit (b) and the rigid support member (a) is provided by two-component injection molding;
whereby fluid flow communication between the discharge conduit and the one or more storage compartments may be established by rotating the discharge conduit around its longitudinal axis relative to the rigid support member from a first position to a second position and whereby the fluid flow communication between the discharge conduit and the one or more storage compartments may be interrupted by rotating the discharge conduit around its longitudinal axis relative to the rigid support member from the second position to the first position, wherein the one or more storage compartments are provided by flexible films made of composite material films, which are attached to the rigid support member.

Claims

1. A unit dose package for a dental composition, comprising: (a) a rigid support member having a proximal end and a distal end, the rigid support member supporting one or more storage compartments for the dental composition and providing fluid flow communication between the one or more storage compartments and one or more discharge orifices, wherein the one or more storage compartments each have a volume of 10 l to 1000 l, and (b) a discharge conduit having a longitudinal axis extending from a proximal end to a distal end, the discharge conduit being rotatably attached to the distal end of the rigid support member for rotation around its longitudinal axis, wherein the attachment of the discharge conduit (b) and the rigid support member (a) is provided by two-component injection molding; whereby fluid flow communication between the discharge conduit and the one or more storage compartments may be established by rotating the discharge conduit around its longitudinal axis relative to the rigid support member from a first position to a second position and whereby the fluid flow communication between the discharge conduit and the one or more storage compartments may be interrupted by rotating the discharge conduit around its longitudinal axis relative to the rigid support member from the second position to the first position, wherein the one or more storage compartments are provided by flexible films made of composite material films, which are attached to the rigid support member.

2. The unit dose package according to claim 1, wherein the composite films are selected from polyethylene/aluminum/polyethylenterephthalate (PE/Al/PET), polypropylene/aluminum/polyethyleneterephthalate(PP/Al/PET), polyethylene/aluminum/oriented polyamide (PE/Al/oPA), polypropylene/aluminum/oriented polyamide (PP/Al/oPA).

3. The unit dose package according to claim 1, wherein the flexible films made of composite material films are attached to the rigid support member by a plastic welding process.

4. The unit dose package according to claim 1, wherein the discharge conduit is received in a rotation symmetrical recess of the rigid support member, wherein one or more discharge orifices are provided.

5. The unit dose package according to claim 1, wherein the recess portion is a cylindrical recess portion having one or more discharge orifices at the cylindrical side walls thereof

6. The unit dose package according to claim 1, wherein the discharge conduit comprises a discharge channel extending from the distal end to the proximal end the front side of which is closed, whereby the fluid flow communication is provided at the proximal end by one or more orifices provided at the side wall of the discharge channel.

7. The unit dose package according to claim 1, wherein the discharge conduit comprises a first member attached to the rigid support member and a second member attached to distal end of the first member so that permanent fluid flow communication is provided between the first member and the second member.

8. The unit dose package according to claim 5, wherein the discharge conduit further comprises a third member attached to the second member so that permanent fluid flow communication is provided between the third member and the second member is provided.

9. The unit dose package according to claim 5, wherein the second member may be rotated relative to the first member around the longitudinal axis of the discharge conduit.

10. The unit dose package according to claim 1, wherein the discharge conduit comprises a static mixer.

11. The unit dose package according to claim 1, wherein the support member further comprises one or more orifices at the proximal end, which provide fluid flow communication with the one or more storage compartments during filling of the unit dose package system, preferably wherein the one or more orifices at the proximal end of the support member are sealed by a cap.

12. The unit dose package according to claim 1, which contains a dental composition having a dynamic viscosity of at most 1 Pas (23 C.).

13. The unit dose package according to claim 10, wherein the dental composition is a dental adhesive containing one or more solvents selected from alcohols, ketones and water; or comprising a dispensing tip provided with an application system selected from a sponge, a flock and a brush.

14. The unit dose package according to claim 1, wherein the support member and at least a first member of the discharge conduit are made by two component injection molding, whereby at least the first member of the discharge conduit and the support member are made of different resin materials.

15. The unit dose package according to claim 1, wherein the unit dose package is capable of dispensing a dental composition selected from the group consisting of a dental adhesive composition, a desensitizer, a pit and fissure sealant and a protective varnish.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0021] FIG. 1 is a perspective side view of a preferred embodiment of the unit dose package according to the present invention.

[0022] FIG. 2 is a cross-sectional side view of the preferred embodiment of the unit dose package according to the present invention shown in FIG. 1.

[0023] FIG. 3 is a cross-sectional view of a preferred embodiment of the rigid support member and of the discharge conduit of the unit dose package of the present invention.

[0024] FIG. 4 is a cross sectional view of a preferred embodiment of the unit dose package of the present invention.

[0025] FIG. 5 is a top view of the rigid support member with the discharge conduit in the activated state for the unit dose package according to the present invention.

[0026] FIG. 6 is a top view of the rigid support member with the discharge conduit in the not activated state for the unit dose package according to the present invention.

[0027] FIG. 7 is a perspective view of the rigid support member of the unit dose package in a preferred embodiment of the unit dose package according to the present invention.

[0028] FIG. 8 is a cross-sectional view of the storage compartments in a preferred embodiment of the unit dose package of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] The present invention provides a unit dose package for a dental composition. The dental composition is preferably a dental composition having a low viscosity. In particular a dental composition having a dynamic viscosity at 23 C. of at most 1 Pas, preferably of at most 100 mPas, more preferably of at most 50 mPas. The dental composition contains preferably one or more solvents selected from water, alcohols or ketones. The dental composition is preferably one selected from a dental adhesive, a desensitizer, a pit and fissure sealant and a protective varnish. Preferably the dental composition is a dental adhesive, more preferably a dental adhesive containing one or more solvents selected from alcohols, ketones and water. In a preferred embodiment the dental composition is a dental adhesive containing one or more solvents selected from 1-propanol, 2-propanol, ethanol, t-butanol, methylethylketone, acetone and water. In a more preferred embodiment of the present invention the dental composition is a dental adhesive containing acetone.

[0030] The unit dose package according to the present invention may preferably hold a dental composition that may be a one-component dental composition. The unit dose package according to the present invention may also hold a dental composition being a two component composition or multiple component composition, whereby the two or multiple components of the dental composition are stored in separate storage compartments in the unit dose package and mixed when the two or multi-components dental composition is dispensed.

[0031] The unit dose package for a dental composition comprises a rigid support member having a proximal end and a distal end. The rigid support member supports one or more storage compartments for the components of the dental composition. The rigid support member further provides fluid flow communication between the one or more storage compartments and one or more discharge orifices. In the case the unit dose package comprises more than one storage compartment, the storage compartments are separated before activation of the unit dose package.

[0032] The unit dose package for a dental composition further comprises a discharge conduit having a longitudinal axis extending from a proximal end to a distal end. The discharge conduit is rotatably attached to the distal end of the rigid support member for rotation around its longitudinal axis. Preferably, the attachment of the discharge conduit and the rigid support member is provided by two-component injection molding. Accordingly, the rigid support member is preferably made of polyethylene or polypropylene resin material. The discharge conduit is preferably made of a material selected from polyamide resin or PBT resin.

[0033] According to the present invention, fluid flow communication between the discharge conduit and the one or more storage compartments may be established by rotating the discharge conduit around its longitudinal axis relative to the rigid support member from a first position to a second position.

[0034] Moreover, according to the present invention, fluid flow communication between the discharge conduit and the one or more storage compartments may be interrupted by rotating the discharge conduit around its longitudinal axis relative to the rigid support member from the second position to the first position.

[0035] The one or more storage compartments of the unit dose package of the present invention are provided by flexible films attached to the rigid support member.

[0036] The discharge conduit may be received in a rotation symmetrical recess of the rigid support member, wherein one or more discharge orifices are provided.

[0037] According to a preferred embodiment, the discharge conduit may be received in a recess portion which is a cylindrical recess portion having one or more discharge orifices at the cylindrical side walls thereof.

[0038] Preferably, the discharge conduit comprises a discharge channel extending from the distal end to the proximal end the front side of which is closed, whereby the fluid flow communication is provided at the proximal end by one or more orifices provided at the side wall of the discharge channel.

[0039] The discharge conduit may further comprise a first member attached to the rigid support member and a second member attached to distal end of the first member so that permanent fluid flow communication is provided between the first member and the second member.

[0040] In a preferred embodiment of the present invention, the discharge conduit further comprises a third member attached to the second member so that permanent fluid flow communication is provided between the third member and the second member.

[0041] The second member may be rotated relative to the first member around the longitudinal axis of the discharge conduit, whether the second member is attached to a third member or not.

[0042] Preferably, the discharge conduit comprises a static mixer.

[0043] According to a preferred embodiment, the support member may further comprise one or more orifices at the proximal end which provide fluid flow communication with the one or more storage compartments during filling of the unit dose package system.

[0044] The one or more orifices at the proximal end of the support member may be sealed by a cap.

[0045] According to a preferred embodiment, the unit dose package contains a dental composition having a dynamic viscosity of at most 1 Pas (23 C.), preferably of at most 100 mPas (23 C.).

[0046] According to a preferred embodiment, the dental composition contains one or more solvents. The solvents may be selected from water, alcohols or ketones. The dental composition is preferably selected from a dental adhesive, a desensitizer, a pit and fissure sealant and a protective varnish.

[0047] According to a preferred embodiment of the unit dose package for a dental composition, the dental composition is a dental adhesive containing one or more solvents selected from water, alcohols and ketones. In a more preferred embodiment of the unit dose package of the present invention, the dental composition is a dental adhesive, preferably a dental adhesive containing one or more solvents selected from t-butanol, ethanol, 1-propanol, 2-propanol, water, methylethylketone and acetone. More preferably, the dental composition is a dental adhesive containing acetone.

[0048] The present invention provides a process for the preparation of a unit dose package of the present invention, wherein the support member and at least a first member of the discharge conduit are made by two component injection molding, whereby at least the first member of the discharge conduit and the support member are made of different resin materials.

[0049] Further the present invention provides the use of the single unit dose of the present invention for dispensing a dental composition selected from a dental adhesive composition, a desensitizer, a pit and fissure sealant and a protective varnish. In a preferred embodiment the unit dose package of the present invention is used for dispensing dental adhesives.

[0050] FIG. 1 shows a perspective side view of a unit dose package 10 for a dental composition according to a preferred embodiment of the present invention. The unit dose package comprises a rigid support member 11.

[0051] The rigid support member 11 may be made of any material suitable for storing and dispensing a dental composition. Preferably, the rigid support member 11 is made of a plastic material. A preferred example of a plastic material is selected from polyethylene (PE) or polypropylene (PP). In view of the nature of the dental compositions in the unit dose package, the selection of the material of the rigid support member 11 is relevant for fulfilling the requirements such as with regard to the shielding of the dental composition against environment, the sealing property of the material in view of the low viscosity, solvents and components in the dental composition, and the stabilization of the dental composition by oxygen transferred from the environment into the dental composition.

[0052] The rigid support member 11 has a proximal end 110 and a distal end 111. The proximal end may be associated with a cap 14. The distal end 111 is associated with a discharge conduit 13.

[0053] The rigid support member 11 supports one or more storage compartments 12 for the dental composition and provides fluid flow communication between the one or more storage compartments 12 and one or more discharge orifices 114. The volume of the one or more storage compartments 12 is not particularly limited as long as a unit dose package having favourable handling and sealing properties may be provided. The one or more storage compartments each have a volume of 10 l to 1000 l, preferably 20 l to 450 l, still more preferably 30 l to 200 l, and still more preferably 50 l to 100 l.

[0054] The one or more storage compartments 12 are provided by flexible films attached to an outer shell of the rigid support member 11. The nature of the flexible films is not particularly limited as long as the flexible films provide good barrier properties against the moisture and the oxygen and ensure good sealing properties. The flexible films are made of composite films. Preferably, the flexible films are composite films selected from polyethylene/aluminum/polyethylenterephthalate (PE/Al/PET), polypropylene/aluminum/polyethyleneterephthalate(PP/Al/PET), polyethylene/aluminum/oriented polyamide (PE/Al/oPA), polypropylene/aluminum/oriented polyamide (PP/Al/oPA). The use of a composite film comprising aluminum provides for light protection without the need of colouring the films. The flexible films made of composite material films are attached to the rigid support member by a plastic welding process. Plastic welding relates to a welding process for semi-finished plastic materials is described in ISO 472 (Plastics-Vocabulary, ISO 472 International Organization for Standardization, Switzerland, 1999) as a process of uniting softened surfaces of materials, generally with the aid of heat (except solvent welding). Welding of thermoplastics is accomplished in three sequential stages, namely surface preparation, application of heat and pressure, and cooling. The plastic welding process used according to the present invention is preferably a heat sealing process. Heat sealing is a process of sealing one thermoplastic to another similar thermoplastic using heat and pressure. The direct contact method of heat sealing utilizes a constantly heated die or sealing bar to apply heat to a specific contact area or path to seal or weld the thermoplastics together. Preferably, the flexible films made of composite material films are attached to the rigid support member without using an adhesive.

[0055] The rigid support member comprises a discharge conduit 13 having a longitudinal axis extending from a proximal end 130 to a distal end 131. The discharge conduit 13 is rotatably attached to the distal end 111 of the rigid support member 11 for rotation around its longitudinal axis.

[0056] The fluid flow communication between the discharge conduit 13 and the one or more storage compartments 12 may be established by rotating the discharge conduit 13 around its longitudinal axis relative to the rigid support member 11 from a first position to a second position. The fluid flow communication between the discharge conduit 13 and the one or more storage compartments 12 may be interrupted by rotating the discharge conduit 13 around its longitudinal axis relative to the rigid support member 11 from the second position to the first position.

[0057] When the discharge conduit closes the discharge orifices of the rigid support member the passage of fluids from the one or more storage compartments to the discharge conduit is not possible. This state of the unit dose package is also indicated as non-activated state. In the non-activated state the filling with the dental composition of the one or more storage compartments is possible.

[0058] When the discharge conduit opens the discharge orifices of the rigid support member, the passage of fluids from the one or more storage compartments to the discharge conduit is possible. Thus, fluid communication between the one or more storage compartments and the discharge conduit is established. This state of the unit dose package is also indicated as activated state. In the activated state the dispensing of the dental composition is possible.

[0059] As shown in FIGS. 2 and 3, according to a preferred embodiment, the discharge conduit 13 is received in a rotation symmetrical recess 115 of the rigid support member 11, wherein one or more discharge orifices are provided 114. Preferably, the discharge conduit 13 is received in a recess portion 115 which is a cylindrical recess portion having one or more discharge orifices 114 at the cylindrical side walls 116 thereof.

[0060] According to a preferred embodiment of the present invention, the discharge conduit 13 comprises a discharge channel 136 extending from the distal end 131 to the proximal end 130 the front side of which is closed, whereby the fluid flow communication is provided at the proximal end 130 by one or more orifices 114 provided at the side wall 116 of the discharge channel 136.

[0061] Preferably, the discharge conduit 13 comprises a first member 132 attached to the rigid support member 11 and a second member 133 attached to the distal end of the first member 132 so that permanent fluid flow communication is provided between the first member 132 and the second member 133. The second member may be attached to the first member by means of a slot and key system.

[0062] The discharge conduit 13 may further comprise a third member 134 attached to the second member 133 so that permanent fluid flow communication is provided between the third member 134 and the second member 133. The third member may be attached to the second member by means of a slot and key system.

[0063] The third member may be an elongated part which may comprise at its free end a dispensing tip. The dispensing tip may be provided with every appropriate application system, such as a sponge, a flock or a brush. The application system may be glued to the dispensing tip with, for example, an epoxy resin. The application system may also be shaped as a ball having, for example, tiny hair made of thermoplastic materials and be co-molded.

[0064] The second member 133 may be rotated relative to the first member 132 around the longitudinal axis of the discharge conduit 13, whether the second member is attached to a third member or not.

[0065] As shown in FIG. 3, the discharge conduit 13 may comprise a static mixer 135. The static mixer mixes the materials stored in the one or more storage compartments as they are dispensed from the cartridge. The static mixer may be any static mixer as long as it provides continuous mixing of the materials. Preferably the static mixer has a cylindrical or squared housing. More preferably the static mixer has a cylindrical housing. In a preferred embodiment of the present invention, the static mixer has a cylindrical housing with helical sections.

[0066] In the FIG. 3 the discharge conduit in the not activated state is shown, i.e. the discharging channel between the one or more storage compartments and the discharge conduit is closed and the fluid flow communication between the one or more storage compartments and the discharge conduit is interrupted.

[0067] The discharge conduit 13 may be provided with an actuation member 137, which facilitates the rotation of the discharge conduit 13 around its longitudinal axis relative to the rigid support member 11. The actuation member may provide also visual evidence of the state, activated or non-activated, of the unit dose package.

[0068] As shown by FIGS. 5 and 6, according to a preferred embodiment, the transition from the activated state to the non-activated state is provided by a 90 rotation of the discharge conduit 13 around its longitudinal axis relative to the rigid support member 11.

[0069] FIGS. 5 and 6 show respectively the activated state, in which one of the discharge orifices to the discharge conduit is open, and the non-activated state, in which one of the discharge orifices to the discharge conduit is closed.

[0070] According to a preferred embodiment, the unit dose package further comprises a tactile and/or acoustic feedback, which provides the user with confirmation of the activation of the unit dose package. A tactile feedback may be a system which offers resistance when the unit dose package is used for the first time. A tactile feedback may be a slot and key system. A tactile and/or acoustic feedback may also indicate to the user whether the unit dose package was already opened and/or manipulated.

[0071] According to a preferred embodiment, the rigid support member 11 further comprises one or more orifices 113 at the proximal end 110 which provide fluid flow communication with the one or more storage compartments 12 during filling of the unit dose package 10.

[0072] FIG. 7 shows a preferred embodiment of the unit dose package 10 of the present invention. At the proximal end 110 of the rigid support member 11 are shown two orifices 113, which are provided, respectively, one for filling the storage compartment with the dental composition and the other one for discharging the air contained in the storage compartment.

[0073] In case the unit dose package 10 comprises two storage compartments 12, when the one or more discharge orifices 114 of the rigid support member 11 are closed, it is possible to fill the two storage compartments 12 in parallel by injecting in each storage compartment the dental composition through one of the two orifices 113 of each storage compartment. At the same time of the filling, the air contained in the storage compartments is discharged through the second other orifices 113 of each storage compartment.

[0074] For example by means of a cannula having a diameter of about 0.5 mm it is possible to fill through one of the orifices the corresponding storage compartment. At the same time, the air present in the compartment can escape through the air discharging orifice. In this way a unit dose package not containing air is produced. By the absence of air which, because of the extrusion of the liquid, does not stay compressed in the storage compartment, and due to the irreversibly deformable flexible foils, no recirculation effect of the air appears.

[0075] FIG. 8 shows a preferred embodiment of the unit dose package of the present invention. The rigid support member supports two storage compartments 12 which are separated by a partition wall 117.

[0076] According to a preferred embodiment, the one or more orifices 113 at the proximal end 110 of the rigid support member 11 are sealed by a cap 14. The cap has preferably a number of pins corresponding to the number of orifices 113 at the proximal end 110 of the rigid support member.

[0077] The present invention also provides a process for the preparation of a unit dose package 10. The support member 11 and at least a first member of the discharge conduit 13 are made by two component injection molding, whereby at least the first member of the discharge conduit and the support member are made of different resin materials.

[0078] The discharge conduit 13 preferably is made of a plastic material having a melting point higher than polyethylene (PE) or polypropylene (PP). Preferably the plastic material of the discharge conduit is selected from polyamide (PA) and polybutyleneterephthalate (PBT). In a preferred embodiment of the present invention the discharge conduit is made of polyamide.

[0079] The rigid support member is preferably made of a plastic material selected from polyethylene (PE) and polypropylene (PP). In a preferred embodiment of the present invention the rigid support member is made of polyethylene.

[0080] According to a preferred embodiment, in the first step of the process for the preparation of a unit dose package according to the present invention the discharge conduit including the discharge channel is moulded. In a second step of the process the rigid support member is produced by moulding around the discharge conduit.

[0081] Subsequently a piston or a stamp having the same shape of the discharge channel is inserted in said discharge channel of the discharge conduit. At the same time the one or more discharging orifices in the rigid support member are produced.

[0082] By cooling of the plastic material, the rigid support member shrinks on the enclosed part of the discharge conduit and forms a proportionately thick and mechanically stable connection. Because of the incompatibility between the plastic materials chosen for the support member and the discharge conduit, there are no interactions between them and neither fusion of one of them. After removal of the injection molding system, the support member and the discharge conduit are in the activated state. By rotation of the discharge conduit around its rotational axis relative to the rigid support member the discharge channel is closed.

[0083] The unit dose package is used for dispensing a dental composition selected from a dental adhesive composition, a desensitizer, a pit and fissure sealant and a protective varnish. Preferably the unit dose package is used for dispensing dental adhesives, more preferably dental adhesives containing one or more solvents selected from t-butanol, ethanol, 1-propanol, 2-propanol, water, acetone, methylethylketone. In a preferred embodiment of the present invention, the unit dose package of the present invention is used for dispensing dental adhesives containing acetone.