WO2025032410A1

WO2025032410A1 - Dental article with application device, lubricant composition and dental material

Info

Publication number: WO2025032410A1
Application number: PCT/IB2024/057151
Authority: WO
Inventors: Andreas J. Boehm; Marc Peuker
Original assignee: Solventum Intellectual Properties Company
Priority date: 2023-08-08
Filing date: 2024-07-23
Publication date: 2025-02-13

Abstract

The invention relates to a dental article (10) comprising an application device (20) with a compartment (30) having an inner surface (31) with a structured surface area comprising recesses (32), a piston assembly (40) moveably located in the compartment (30), the piston assembly comprising a piston body (41), a dispensing section (50) located at the distal end of the compartment, a lubricant composition (60) located at least in the recesses of the structured surface area (32), a dental material (70) being located in the compartment in contact with the lubricant composition (60).

Description

DENTAL ARTICLE WITH APPLICATION DEVICE, LUBRICANT COMPOSITION AND DENTAL MATERIAL

Field of the Invention

The invention relates to a dental article comprising an application device with a compartment, a lubricant composition and a dental material, wherein the dental material is in contact with the lubricant composition during the dispensing process of the dental material stored in the compartment of the application device.

Background

Dental materials, in particular dental composite material, are widely used for restoring defect dental tooth structure in the mouth of a patient.

Dental materials often contain polymerizable (meth)acrylate components, filler and an initiator system suitable for hardening the dental material by applying radiation.

In particular, dental composite materials typically have a high filler load which is needed for achieving adequate mechanical properties after hardening of the material.

The high filler load usually results in a high viscous material which needs to be adequately stored before use to avoid an undesired polymerization.

As suitable packaging devices screw syringes and so-called composite capsules are often proposed. Both packaging devices allow the extrusion of the stored dental composite material through a nozzle to a dental surface to be treated.

However, due to the high viscosity of the dental composite material high extrusion forces are typically required. The high extrusion forces can either be achieved by using a screw thread with an adequate piston or by using a suitable applier.

Packaging devices for storing dental material are described in various documents.

US 5,603,701 (Fischer) describes a syringe apparatus for delivering solid, yet pliable materials, such as dental composites. The syringe apparatus comprises an unthreaded barrel means for containing the material. The unthreaded barrel means has an inlet end, an outlet end, and an enlarged finger grip at the inlet end. The syringe apparatus also comprises means for slidably engaging the finger grip of the barrel means, the engaging means having a threaded throughbore. The syringe apparatus further comprises a plunger means for movement through the barrel means.

US 4,863, 072 (Perler) describes an apparatus for the delivery of light-curable composite dental filling material comprises a tubular composite reservoir, plunger and slider. The slider is free to move longitudinally along the reservoir but is matingly mounted to facets on the outside surface of the reservoir to prevent angular movement of the slider relative to the reservoir. The plunger consists of a shaft threaded to mate with the threaded inside diameter of the composite reservoir. US 11,351,009 B2 (Clark et al.) describes a capsule for use in a dental composite dispenser, comprising a hollow body with a wall defining an interior space of the body, the body including a proximal end and a distal end having a dispensing orifice; a first composite resin positioned in the interior space of the body; and a second composite resin positioned in the interior space of the body, wherein the first composite resin has a first viscosity, the second composite resin has a second viscosity less than the first viscosity, wherein no barrier is positioned between the first composite resin and the second composite resin, wherein the second composite resin is configured to be extruded through the dispensing orifice prior to the first composite resin, and wherein the first composite resin and the second composite resin are in contact before use of the capsule in the dental composite dispenser.

US 2022/023538 Al (Boehm et al.) describes a syringe for storing and dispensing a first and a second component of a material. The syringe has a first chamber containing the first component and a second chamber containing the second component. The syringe further has an empty blank chamber that spaces the first and second chamber from each other.

US 2016/296962 Al (Maxa) describes devices for dispensing compositions, the device having a tip (72) including an inner tapered funnel portion (74); a hollow barrel (84) including an outer tapered surface portion (86), an inner surface, an open front end, and an open back end opposite the front end; and a piston (16), where the outer tapered surface portion of the barrel aligns and releasably engages with the inner tapered funnel portion of the tip, and where the piston is in sliding engagement with the barrel.

Similarly, appliers for dispensing dental composite materials from packaging devices are also described in the literature.

US 6,790,037 Bl (Orecchia) describes a viscous material dispenser for applying a viscous dental material from a capule, cartridge or capsule. The dispenser includes a locking mechanism mounted on the syringe type dispenser to securely retain the capule, cartridge or capsule within the syringe type dispenser while the viscous material is being applied from the syringe type dispenser.

US 10,016,257 B2 (Pauser) describes a pen-like dispenser for dispensing a dental material has a handle and a cover which are attached for rotation relative to each other about a longitudinal axis of the dispenser, and a cartridge for holding the dental material and a screw plunger for extruding the dental material from the cartridge by screwing action.

For reducing the application force, it has also been suggested to warm the dental composite materials and thus reduce the viscosity.

Devices and processes for warming dental composite materials are e.g., described in WO 2021/053408 Al (3M), WO 2020/025485 Al (Voco).

Further, it was observed that the application of high forces to high viscous dental composite materials may cause a so-called “run-on” of the dental composite material even after the dispensing is completed, because during the extrusion process the high viscous dental composite material often expands the cartridge in length and diameter and needs an appropriate time to relax after the extrusion force has been applied by the screw/thread.

Common to all devices is that the dispensing of the dental material from those devices is often cumbersome as the dental material is typically sticky and high viscous.

For reducing the friction during the dispensing process it has also been proposed to apply a lubricant on the inner surface of the device. However, when extruding the dental composite material from the packaging device, the lubricants are often extruded as well. This may have an undesired impact on the properties of the dental composite material during and after curing.

None of the solutions known to the practitioner so far is fully satisfying.

Summary of Invention

There is still a need for an improved dental article or application device suitable for storing and dispensing dental materials.

In particular, there is a need for an application device for storing and dispensing dental materials having a high viscosity.

Thus, one object of the invention is to provide an article or device which allows the dispensing of in particular high viscous dental materials more easily, preferably with less exertion.

Ideally, it should be possible to dispense the dental material from the article or the device without the need for supplemental gadgets or devices.

It was found that during the dispensing of dental material from a device containing a lubrication material on its inner surface for reducing friction, the lubrication material often starts accumulating at the distal end of the device.

The accumulated lubrication material is then often dispensed from the device together with the dental material. This may have an undesired impact on the overall performance and physical properties of the dental material after hardening.

Thus, it would also be desirable that the dispensing of the dental material from the application device does not negatively affect the overall performance of the dental material during use.

One or more of these objects are addressed by the present invention.

The invention relates a dental article, a process of production, a process for dispensing and a kit of parts as described in the present text and the claims.

In one aspect the invention relates to a dental article (10) comprising an application device (20) with a compartment (30) having an inner surface (31) with a structured surface area comprising recesses (32), a piston assembly (40) moveably located in the compartment (30), the piston assembly comprising a piston body (41), a dispensing section (50) located at the distal end of the compartment, a lubricant composition (60) being located at least in the recesses of the structured surface area (32), a dental material (70) being located in the compartment in contact with the lubricant composition (60).

The invention also relates to a process for producing such a dental article, the process comprising the steps of providing the application device (20) described in the present text, applying the lubricant composition (60) described in any of the proceeding claims into the recesses (32) of the structured surface area of the inner surface (31) of the compartment (30) of the application device (20), placing the dental material (70) described in any of the proceeding claims into the compartment (30) in contact with the lubricant composition (60), inserting the piston assembly (40) described in any of the proceeding claims into the compartment (30).

The invention also relates to a process of dispensing the dental material from the dental article.

Another aspect of the invention is directed to a kit of part comprising the dental article (10) described in the present text and the following items alone or in combination: dental curing light, dental etchant, dental primer, dental adhesive, dental cement.

Unless defined differently, for this description the following terms shall have the given meaning: A “dental article” means an article which is to be used in the dental or orthodontic field, especially a dental article being suitable for supporting the restoration of a dental tooth.

A “dental material” means a material intended to be used in dental practice. More particularly, dental materials include dental composite materials, dental cements, dental adhesives, dental crown and bridge materials. Those materials are typically used for restoring a dental tooth. Examples of dental restorations include crowns, bridges, inlays, onlays, veneers, facings, copings, crown and bridged framework, and parts thereof.

Dental materials are typically hardenable compositions, which can be hardened at ambient conditions, including a temperature range of 15 to 50°C or 20 to 40°C within a time frame of 30 min or 20 min or 10 min. Higher temperatures are not recommended as they might cause pain to the patient and may be detrimental to the patient's health. Dental materials are typically provided to the practitioner in comparable small volumes, that is volumes in the range of 0.1 to 100 ml or 0.5 to 50 ml or 1 to 30 ml.

A “hardenable or curable or polymerizable component” is a component which can be cured or solidified in the presence of a photo-initiator by radiation-induced polymerization or by using a redox-initiator system. A hardenable component may contain one, two, three or more polymerizable groups. Typical examples of polymerizable groups include unsaturated carbon groups, such as a vinyl group. An example is a (methyl)acrylate group.

As used herein, “hardening” or “curing” a composition are used interchangeably and refer to polymerization and/or crosslinking reactions including, for example, photo -polymerization reactions and chemical-polymerization techniques (e. g., ionic reactions or chemical reactions forming radicals effective to polymerize ethylenically unsaturated compounds) involving one or more materials included in the composition.

An “initiator or initiator system” is a component or a combination of components being able to start the curing process of a hardenable component.

“Proximal” means a part of a body or article that is closer to the practitioner during use. For a syringe assembly, the rear end receiving the plunger or piston is the proximal end of the syringe assembly.

“Distal” means the opposite of proximal. For a syringe assembly, the front or dispensing end is the distal end of the syringe assembly.

As used herein, “a”, “an”, “the”, “at least one” and “one or more” are used interchangeably. Also herein, the recitations of numerical ranges by endpoints include all numbers subsumed within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.).

Adding an “(s)” to a term means that the term should include the singular and plural form. E.g., the term “additive(s)” means one additive and more additives (e.g., 2, 3, 4, etc.).

Unless otherwise indicated, all numbers expressing quantities of ingredients, measurement of physical properties such as described below and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about”.

The terms “comprise” or “contain” and variations thereof do not have a limiting meaning where these terms appear in the description and claims. “Consisting essentially of’ means that specific further components can be present, namely those which do not materially affect the essential characteristic of the article or composition. “Consisting of’ means that no further components should be present. The term “comprise” shall include also the terms “consist essentially of’ and “consists of’.

Brief Description of Figures

Fig. 1 shows a perspective view of an embodiment of the dental article.

Fig. 2 shows a schematic axial cross-sectional view of the dental article.

Fig. 3A shows a schematic axial cross-sectional view of the dental article with one option for a ridge/groove design.

Fig. 3B shows a schematic axial cross-sectional view of the dental article with another option for a ridge/groove design.

Fig. 4A shows an enlarged view of the proximal end of the dental article with one option for a back side seal.

Fig. 4B shows an enlarged view of the proximal end of the dental article with another option for a back side seal. Detailed Description

It has been found that the application device described in the present text has a couple of advantageous properties.

The dental article is not only suitable for storing dental materials but also facilitates the dispensing of the dental material stored in the dental article during use.

The lubricant composition on the inner surface of the compartment is suitable for reducing the friction of the dental material on the inner surface of the compartment.

This enables the dispensing of the dental material from the article without the need of supplemental equipment such as a caulk-gun like application device.

The presence of a structured surface area with recesses where the lubricant composition is located helps to further reduce friction between the dental material stored in the compartment of the application device and the piston assembly on the one hand and the inner surface of the compartment on the other hand. Depending on the formation of the structured surface area a huger amount of lubricant composition can be stored.

Further, as the lubricant composition is mainly located in the recesses of the structured surface area, most of the lubricant composition remains in place during the dispensing process of the dental material.

Thus, the dental material can be dispensed with less efforts, and the risk of contamination of the dental material during the dispensing process is reduced.

Further advantages can be seen in that the dental material can be dispensed from the application device by the practitioner with using only one hand. Thus, the need for additional dental assistance can be reduced.

Aside from that, if desired the dental material can be dispensed directly into a cavity of a tooth and the content or volume of the dental material stored in the device is sufficiently large for filling big cavities or multiple cavities. Thus, there is no need for placing a new capsule, which is filled with dental material, into a dental composite dispenser as it is currently suggested in the prior art.

The invention is directed to a dental article comprising an application device, a dental material and a lubricant composition.

The application device comprises a compartment, a piston assembly, and a dispensing section.

The compartment can be characterized by having a proximal end, a distal end, an inner diameter D_c and an axial length L_c.

The length and diameter of the compartment essentially defines the volume of the packaging device which is available for receiving the dental material to be stored in the packaging device.

The volume of the compartment is typically in a range of 0.1 ml to 100 ml or 0.5 to 50 ml or 1 to 30 ml.

The inner diameter of the compartment is typically in the range of 2 to 25 mm. The outer diameter of the compartment is typically in the range of 4 to 30 mm.

The wall-thickness of the compartment is typically in the range of 0.5 to 2 mm.

The ratio of length to inner diameter of the compartment is typically in the range of 25/1 to 3/1.

Such a ratio was found to be useful as it provides a good balance between the diameter available for transferring force to the dental material during the extrusion process and handling of the dental product by the practitioner.

The compartment is typically tube-shaped.

Overall, the application device may have the shape of a syringe with a tubular hollow barrel with a front end and a rear end opposite the front end.

The compartment comprises an inner surface. The inner surface comprises a structured surface area. The structured surface area comprises recesses.

The configuration and/or arrangement of the recesses is not particularly limited. However, the recesses should be designed or shaped to allow the application and/or placement of the lubricant composition.

Recesses resulting from the presence of the following features alone or in combination was found to be advantageous: (a) surface roughness, (b) ridges; (c) grooves.

A surface roughness Ra in the range of 5 to 50 pm or 10 to 40 pm was found to be useful. Such a surface roughness can be obtained e.g., by sandblasting of the inner surface of the compartment.

If present, the ridges extend from the inner surface of the compartment in radial direction into the compartment.

If present, the grooves are present in the inner surface of the compartment.

If present, the ridges and/or grooves are typically symmetrically arranged on the inner surface of the compartment.

However, the arrangement of the ridges and/or grooves on the inner surface of the compartment is not particularly restricted, either.

The direction can be axial, that is in the direction from the proximal end of the compartment to the distal end.

However, also a radial arrangement on the inner surface of the compartment is possible.

The ridges and/or grooves may also be arranged helically.

However, an axial arrangement in proximal/distal direction can be preferred as it may facilitate the application of the lubricant composition into the recesses. Such an arrangement is also more cost effective to manufacture e.g., by injection moulding.

The structured surface area may extend at least over 50% or 60% or 70% or 80% or 90% of the axial length L_c of the compartment.

The structured surface area may extend from a seal located at the proximal opening of the compartment to the distal opening. The depth or height DR of the grooves or recesses is typically in a range of 0.05 to 0.5 mm or 0.1 to 0.3 mm.

Such a dimension was found to be advantageous as it still allows the dispensing of the dental material through the dispensing section of the application device without running the risk that the dental material flows back through the recesses in proximal direction.

Typically, there are at least 3, 4 or 5 ridges and/or grooves.

There is no particular upper limit for the number of ridges and/or grooves, however, typically there are not more than 80, 70 or 60 ridges and/or grooves.

Thus, a number of ridges and/or grooves in the range of 3 to 80, or 4 to 70, or 5 to 60 can be preferred.

Such a number of grooves and/or ridges was found to be suited for appropriately storing the lubricant composition on the one hand and for providing a sufficient guidance for the piston assembly during the dispensing process of the dental material.

The compartment typically comprises at least one seal.

One seal (seal Al) is typically located at and surrounding the proximal opening of the compartment.

Seal Al may contribute to the avoiding of an undesired leaking or dispensing of the lubricant composition from the dental article during use in proximal direction.

The presence of a seal in proximal direction is often preferred as the risk of an undesired leaking of the lubricant composition in this direction due to the advanced movement of the piston assembly during use is often higher and the contamination of a piston rod during use can be reduced.

Seal Al located at the proximal opening of the compartment can be a lip seal or a gap seal, wherein using a gap seal is sometimes preferred as it may be better suited to seal the proximal opening.

For enabling a tight seal, seal Al may partially extend into the inner area of the compartment in distal direction (e.g., up to 5% of the axial length of the compartment). A seal with such a shape may act as a kind of plug or stopper for the lubricant composition.

The gap seal can be made of only one part but may also comprise two parts which may be made from different materials.

For enabling a tight seal, the gap seal is often made of a material which is softer than the material of the compartment and/or piston assembly.

However, for simplifying the production process of the application device, it is also possible that the lip seal is made of the same material the compartment is made of. The lip seal can be a part of or an extension of the compartment in proximal direction. Within the compartment, in particular at the rear or proximal end of the compartment, a piston assembly can be inserted, which is in sliding engagement with the inner surface of the compartment. That is, the piston assembly is movable within the compartment.

The piston assembly is also for sealing the rear end of the compartment and for transferring pressure to the dental material during the extrusion or dispensing process.

The piston assembly comprises a piston body, which typically has a cylindrical shape with a diameter D_PB.

During use of the dental article, the front end of the piston body is in contact with the dental material.

The piston assembly may further comprise a piston rod.

If present, the piston rod is connected to or is attachable to the proximal end of the piston body. Once attached to the piston assembly, the piston rod should remain in its attached position during use of the dental article.

If desired, the piston assembly and the piston rod, if present, can be made of one part. Thus, both parts, the piston body and the piston rod can be sections of one single plunger.

The dental article typically also comprises a dispensing section through which the dental material can be dispensed.

The dispensing section is located at the distal end of the compartment.

The dispensing section may be tapered and/or comprises a dispensing nozzle. The tapered section may comprise a conical inner surface.

The dispensing nozzle may be releasably engaged or attached to the compartment.

Both parts, the compartment and the dispensing section can be made out of the same material.

The dispensing section does not have a structured inner surface. The inner surface of the dispensing section is smooth.

At the distal end the opening of the compartment is typically narrower than the maximal inner diameter of the compartment. This may help to reduce the risk that portions of the lubricant composition simply flow out at the distal end during the dispensing process. Narrower means that the diameter at the distal end typically corresponds to or has a diameter of at most the diameter of the dental material strand stored in the compartment.

The dental article further comprises a lubricant composition.

During storage the lubricant composition is located on the inner surface of the compartment, in particular in the recesses of the structured surface area.

Typically, the thickness of the layer of the lubricant composition is in a range of 1 to 500 pm or 5 to 300 pm. If desired, the thickness of the layer can be determined with a microscope by cutting the application device and inspecting the interface of the dental material and the inner wall of the compartment.

The viscosity of the lubricant composition is typically in the range of 1 to 10,000 Pa*s or 10 to 1,000 Pa*s or 20 to 800 Pa*s at a temperature of 25°C and a shear rate of 10 s'¹, wherein a range of 10 to 1,000 Pa*s or 20 to 800 Pa*s is sometimes preferred.

Such a viscosity was found to be useful as it facilitates the coating of the inner surface of the compartment of the packaging device during production.

The viscosity is sufficiently low for enabling a homogenous coating and sufficiently high for reducing the risk that the lubricant composition drops or flows down from the inner surface of the compartment of the packaging device.

Regarding its chemical properties and/or chemical composition, the lubricant composition is compatible with the dental material.

The lubricant composition may comprise a monomer with an ethylenically unsaturated group and optionally a filler.

The monomer typically has a molecular weight in the range of 130 to 1,200 g/mol or 130 to 1,000 g/mol or 130 to 800 g/mol or 130 to 600 g/mol.

The lubricant composition may comprise (meth)acrylate monomers, that is, components which can be copolymerized with other polymerizable components which are typically present in a dental material.

The lubricant composition may further comprise fdler. One or more fillers can be present. Adding a filler can be beneficial e.g., for adjusting the rheological properties like viscosity.

The lubricant composition may fiirther comprise an initiator. One or more initiators may be present. Suitable initiators which can be present include photo-initiator systems and/or redox-initiator systems.

The dental article further comprises a dental material.

The dental material is located in the compartment of the dental article.

The dental material is in contact with the lubricant composition. That is, the lubricant compositions functions as an interface between the inner surface of the compartment and the dental materials stored therein.

The lubricant layer is surrounding the dental material in the area where the dental material would otherwise be in direct contact with the inner surface of the compartment of the dental article.

The dental material is different with respect to its chemical composition from the lubricant composition.

The dental material stored in the dental article of the present text is a material comprising polymerizable components, in particular ethylenically unsaturated groups. The dental material may further comprise filler. The filler of the dental material can be same as or different from the filler which may be present in the lubricant composition.

The dental material may further comprise an initiator. The initiator can be same as or different from the initiator which may be present in the lubricant composition.

The dental article can be further characterized by the following features alone or in combination:

(a) The inner diameter of the compartment D_c is larger than the diameter of piston body D_PB.

(b)The axial length of the compartment L_c is larger than the inner diameter of the compartment D_c at least by a factor of 5.

(c) The volume of the lubricant composition VLC located in the recesses is lower than the volume of the dental material VDM at least by a factor of 4 or 6 or 8.

(d)The viscosity of the dental material ViscDM is larger than the viscosity of the lubricant composition ViscLc.

(e) The ratio of depth or height of the grooves or recesses D_R to the inner diameter of the compartment Dc is typically in a range of 1/10 to 1/200, or 1/20 to 1/100.

A combination of the following features is often preferred: (b) and (c); or (b) and (d); or (b), (c) and (d); or (c) and (e); or (b), (c), (d) and (e).

In one aspect, the dental article can be characterized by the following features in combination:

The axial length of the compartment L_c is larger than the inner diameter of the compartment D_c at least by a factor of 5.

The volume of the lubricant composition VLC located in the recesses is lower than the volume of the dental material V_DM at least by a factor of 4.

The viscosity of the dental material ViscDM is larger than the viscosity of the lubricant composition Visc c.

The ratio of depth or height of the grooves or recesses DR to the inner diameter of the compartment D_c is typically in a range of 1/10 to 1/200.

The lubricant composition comprises polymerizable components.

The dental material comprises polymerizable components and an initiator system for curing the polymerizable components.

The invention is also directed to a process of producing the dental article described in the present text.

Such a process typically comprises the following steps: providing the application device as described in the present text, applying a layer of lubricant composition as described in the present text into recesses of the structured surface area of the inner surface of the compartment of the application device, placing a dental material as described in the present text into the compartment in contact with the lubricant composition, inserting a piston assembly as described in the present text into the proximal end of the tube-shaped compartment.

The application device itself is typically produced by injection-molding. Alternatively, the application device can also be produced by 3d-printing.

The lubricant composition can be applied by spraying or coating with an appropriate coating device e.g., a sponge impregnated with the lubricant composition.

The application device and its individual parts are typically made out of plastic, preferably materials which can be injection molded. The material of the application device is typically selected from PP (polypropylene), PE (polyethylene), PA (polyamide), PBT (polybutadiene terephthalate), PET (polyethylene terephthalate), COC (cycloolefin-copolymer).

To prevent an undesired curing of the dental material during storage, the material of the application device, and in particular the material of the compartment is typically non-transparent to visible light (380 to 750 nm).

If desired and for further protecting the dental material from light during storage, the dental article can comprise a removable cap at the dispensing section.

The production and/or assembly of the dental article can be done at different times and/or locations. E.g., the producing of the application device can be done at one location and the placings of the lubricant composition and the dental material can be done at a different location.

The invention is also directed to a process of dispensing the dental material from the dental article described in the present text.

The process for dispensing comprises the steps of optionally removing a cap from the dispensing section of the dental article, applying an extrusion force to the piston assembly and/or the dental material located at the proximal end of the compartment of the dental article, the extmsion force being typically in a range of 5 to 150 N, or in a range of 5 to 60N.

The force to be applied is in a range which can be provided by a practitioner without big efforts and without the need for using additional gadgets such as a caulking gun or specific packaging devices such as screw syringes.

By moving the piston assembly in distal direction, the dental material stored in the tube-shaped compartment is dispensed.

The dental article described in the present text can also be used in a method for treating a dental situation in the mouth of a patient, the method comprising the steps of applying at least a portion of the dental material located in the compartment of the dental article to the dental situation in the mouth of a patient to be treated, applying radiation to the applied portion of the dental material.

The invention is also directed to a kit of parts comprising the dental article described in the present text and the following items in addition alone or in combination: dental curing light, dental etchant, dental primer, dental adhesive, dental cement.

Dental adhesives are typically acidic dental composition with a rather low viscosity (e.g., 0.01 to 3 Pa*s at 25°C). Dental adhesives directly interact with the enamel or dentin surface of a tooth. Dental adhesives are typically one-part compositions, are radiation-curable and comprise ethylenically unsaturated component(s) with acidic moiety, ethylenically unsaturated component(s) without acidic moiety, water, sensitizing agent(s), reducing agent(s) and additive(s).

Examples of dental adhesives are described in US 2020/0069532 Al (Thalacker et al.) and US 2017/0065495 Al (Eckert et al.). Dental adhesives are also commercially available, e.g., 3M™ Scotchbond™ Universal (3M Oral Care).

Suitable dental primers are described in US 6,126,922 (Rozzi et al.) and WO 00/69393 Al (3M). Dental primers are also commercially available, e.g., 3M™ Transbond™ XT Primer (3M Oral Care).

Dental cements which can be added to the kit include in particular self-adhesive resin cements, which contain an acidic polymerizable component (e.g., a (meth)acrylate component bearing a phosphoric or carboxylic acid moiety), polymerizable components without an acidic moiety, an initiator system and filler.

Suitable dental cements are also commercially available, such as RelyX™ Unicem 2, RelyX™ Universal or RelyX™ Luting Plus (3M Oral Care).

Suitable dental curing lights are described in US 10,758,126 B2 (Geldmacher et al.) or US 10,231,810 B2 (Gramann et al). Dental curing lights are also commercially available, e.g., 3M™ Elipar™ S10 or 3M™ Elipar™ DeepCure S LED curing light (3M Oral Care).

The instruction for use describes how the dental product should be used in daily practice, e.g., outlining the application steps and optional curing conditions.

The dental article described in the present text is not for applying materials intramuscular or intravenous of a human being. Similarly, the dental article is not for sampling body fluids (e.g., blood) from a human being.

The following description of the figures is given to illustrate the invention.

Reference signs and possible and preferred ranges or dimensions of the dental article are further described in the table below.

Fig. 1 shows a perspective view of an embodiment of the dental article (10). At the distal end of the application device (20) there is a dispensing section (50). Shown is also a piston rod (44) for transferring pressure on the piston assembly located within the compartment of the application device (not shown).

Fig 2 shows a schematic axial cross-sectional view of the dental article (10). The dental article (10) comprises a compartment (30) with an inner surface (31), a proximal opening (33) and a distal opening (34). The compartment has a maximal inner diameter D_c (35) and an axial length L_c (36). The inner surface is structured (not shown). On the inner surface (31) there is located a lubrication composition (60) which is in contact with a dental material (70). The dental material (70) extends essentially from the distal opening (34) to the front end of a piston assembly (40) which has been inserted in the compartment (30). The lubricant composition (60) extends essentially from the distal opening (34) to the proximal opening (33) of the compartment (30). At the proximal opening (33) of the compartment (30) there is a seal A (37).

At the distal end the compartment is slightly narrower than the maximal inner diameter (35) of the compartment so that the lubricant composition (60) is not able to simply flow out at the distal end during the dispensing process.

Fig 3A shows a schematic radial cross-sectional view of the dental article with one option for a ridge/groove design in proximal/distal direction. On the inner surface of the compartment (30) a lubrication composition (60) is located. The lubrication composition (60) is mainly located in recesses (32) which result from ridges (38) extending from the inner surface (31) radially into the compartment up to a height DR (39). Six ridges are shown. The lubrication composition (60) is in contact with the dental material (70).

Fig 3B shows a schematic radial cross-sectional view of the dental article with another option for a ridge/groove design. The dental article contains a dental material (70) which is contact with a lubrication composition (60), which is mainly located in ridges (38). In this embodiment, about thirty -two ridges are shown.

Fig 4 A shows an enlarged view of the proximal end of the dental article (10) with one option for a seal A (37), which in this embodiment has the shape of a lip seal. Shown is also the lubrication composition (60) and a piston assembly (40) located within the compartment.

Fig 4B shows an enlarged view of the proximal end of the dental article with another option for a seal A (37), which in this embodiment has the shape of a gap seal extending into the compartment in distal direction. The gap seal comprises two separate parts which can be made from two different materials. However, it is also possible that the gap seal is made of only one part. Shown is also the lubrication composition (60) and a piston assembly (40) located within the compartment. The complete disclosures of the patents, patent documents, and publications cited herein are incorporated by reference in their entirety as if each were individually incorporated. Various modifications and alterations to this invention will become apparent to those skilled in the art without departing from the scope and spirit of this invention.

The above specification, examples and data provide a description of the manufacture and use of the compositions and methods of the invention.

The invention is not limited to the embodiments disclosed herein. One skilled in the art will appreciate that many alternative embodiments of the invention can be made without departing from the spirit and scope thereof.

If desired, the viscosity of the lubricant composition and/or dental material described in the present text can be measured with a Physica MCR 301 (Anton Paar Germany GmbH, Ostfildem- Schamhausen). Flowable composites and monomers can be measured at 25.0°C with a shear rate of 10/s with a 15 mm plate/plate system and a gap of 0.2 mm.

If desired, extrusion force can be measured with a universal testing machine from ZwickRoell: Zwick 010, Load cell Xforce K, Nominal Force lOkN, testing speed 0.25 mm/s.

The sample to be tested (packaging device with lubricant composition and dental material) is placed vertically in a sample holder in a universal testing machine, the front outlet is pointing downwards. On top of the syringe’s plunger, the bolt with its attached load cell of the testing machine is applied to press out the dental material from the application device at ambient conditions (23°C). During this process the applied force is recorded.

If desired, the surface roughness Ra can be determined according to EN ISO 4287:2010-07 e.g., using a profilometer Mahr S2 (Mahr GmbH) applying the stylus method. The surface roughness is given in pm. A length of the test track of about 1 cm is considered sufficient.

Claims

1. A dental article (10) comprising an application device (20) with a compartment (30) having an inner surface (31) with a structured surface area comprising recesses (32), the structured surface area (32) extending over at least 50% of the axial length L_c of compartment (30), a piston assembly (40) moveably located in the compartment (30), the piston assembly comprising a piston body (41), a dispensing section (50) located at the distal end of the compartment, a lubricant composition (60) being located at least in the recesses of the structured surface area (32), a dental material (70) being located in the compartment in contact with the lubricant composition (60).

2. The dental article (10), in particular according to claim 1, the dental article comprising an application device (20) with a compartment (30), the compartment having an inner surface (31) with a structured surface area comprising recesses (32), a proximal opening (33), a distal opening (34), a maximum inner diameter D_c (35), and an axial length L_c (36), a piston assembly (40) moveably located in the compartment (30), the piston assembly (40) comprising a cylindrical piston body (41) with a diameter D_PB (42), and optionally a piston rod (44) connected to or attachable to the piston body (41), a dispensing section (50) located at the distal opening (33) of the compartment (30), a lubricant composition (60) with a volume VLC and a viscosity Visci.c. the lubricant composition being located on the structured surface area (32) of the inner surface of the compartment (30), and a dental material (70) with a volume VD and a viscosity ViscDM, the dental material comprising polymerizable components and being located in the compartment (30) in contact with lubricant composition (60).

3. The dental article according to any of the preceding claims, the application device comprising a seal A (37) surrounding the proximal opening (33) of compartment (30).

4. The dental article according to any of the preceding claims, seal A being a lip seal, or a gap seal.

5. The dental article according to any of the preceding claims, the lubricating composition (60) comprising polymerizable components.

6. The dental article according to any of the preceding claims, the dental material (70) comprising an initiator system for curing polymerizable components.

7. The dental article according to any of claims 2 to 6, the structured surface area (32) having a roughness Ra in the range of 5 to 50 pm.

8. The dental product according to any of the preceding claims, the recesses (32) of the structured surface area resulting from the presence of at least one of the following: surface roughness, ridges, grooves.

9. The dental product according to claim 8, the recesses (32) resulting from the presence of grooves and/or ridges, and the grooves and/or ridges being symmetrically arranged on the inner surface (31) of compartment (30).

10. The dental article according to any of claims 8 to 9, the recesses (32) resulting from the presence of grooves and/or ridges, wherein at least 3 ridges and/or grooves (32) are present.

11. The dental article according to any of claims 2 to 10 characterized by the following equations alone or in combination: a) De > D_PB; b) Lc / D_c > 5; c) VLC / V_D > 50; d) ViscDM > ViscLc-

12. A process of producing the dental article described in any of the preceding claims, the process comprising the steps of providing the application device (20) described in any of the proceeding claims, applying the lubricant composition (60) described in any of the proceeding claims into the recesses (32) of the structured surface area of the inner surface (31) of the compartment (30) of the application device (20), placing the dental material (70) described in any of the proceeding claims into the compartment (30) in contact with the lubricant composition (60), inserting the piston assembly (40) described in any of the proceeding claims into the compartment (30).

13. The dental article according to any of claims 1 to 11 for use in a method for treating a dental situation in the mouth of a patient, the method comprising the steps of applying at least a portion of the dental material (70) located in the compartment (30) of the dental article to the dental situation to be treated, applying radiation to the applied portion of the dental material.

14. The dental article for use according to the preceding claim, the applying step of at least one portion of the dental material (70) comprising the step of applying an extrusion force to the dental material (70) located at the proximal end of the compartment (30) of the dental article (10), the extrusion force being preferably in a range of 5 to 150 N.

15. A kit of parts comprising the dental article (10) described in any of claims 1 to 11 and the following items alone or in combination: dental curing light, dental etchant, dental primer, dental adhesive, dental cement.