Process of warming a dental composite material and kit of parts

Abstract

The invention relates to a process of warming a dental composite material, the process comprising the steps of inserting an application device having the shape of a syringe into an opening of a heating device, the application device comprising a compartment having a proximal end, a distal end, an inner surface, an inner diameter and an axial length Lc, a piston assembly with a proximal end and a distal end, the piston assembly being moveably located in the compartment, a dispensing section with a nozzle located at the distal end of the compartment having an opening less than 3 mm in diameter, the dispensing section being an integral part of the application device, a backplate section located at the proximal end of the compartment, a pressure plate located at the proximal end of the piston assembly, the dental composite material being located in the compartment of the application device, the dental composite material having a viscosity in the range of 5 to 20 kPa*s at 5 23°C, the heating device comprising a housing with an opening for receiving the application device, a heating element, a temperature sensor, a controller, warming the dental composite material located in the compartment of the application device up to a temperature not higher than 70°C.

Description

[0001] PROCESS OF WARMING A DENTAL COMPOSITE MATERIAL AND KIT OF PARTS

[0002] Field of the Invention

[0003] The invention relates to a process of warming a dental composite material located in a compartment of an application device by using a heating device and a related kit of parts.

[0004] The application device has the shape of a syringe and allows the dispensing and application of several portions of the dental composite material after warming.

[0005] Background

[0006] Dental materials, in particular dental composite material, are widely used for restoring defect dental tooth structure in the mouth of a patient.

[0007] Dental materials often contain polymerizable (meth)acrylate components, filler and an initiator system suitable for hardening the dental material by applying radiation.

[0008] In particular, dental composite materials typically have a high filler load which is needed for achieving adequate mechanical properties after hardening of the material.

[0009] The high filler load usually results in a high viscous material which needs to be adequately stored before use to avoid undesired polymerization.

[0010] As suitable packaging devices screw tubes and so-called capsules (single dose application) are often proposed.

[0011] Both packaging devices allow the extrusion of the stored dental composite material through a nozzle.

[0012] However, due to the high viscosity of the dental composite material high extrusion forces are typically required.

[0013] The high extrusion forces can either be achieved by using a screw thread with an adequate piston or by using a suitable applier.

[0014] Packaging devices for storing dental material are described in various patent documents.

[0015] 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.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] Similarly, appliers for dispensing dental composite materials from packaging devices are also described in the patent literature.

[0020] US 6,790,037 Bl (Orecchia) describes a viscous material dispenser for applying a viscous dental material from a carpule, cartridge or capsule. The dispenser includes a locking mechanism mounted on the syringe type dispenser to securely retain the carpule, cartridge or capsule within the syringe type dispenser while the viscous material is being applied from the syringe type dispenser.

[0021] 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.

[0022] For reducing the application force, it has also been suggested to warm the dental composite materials and thus reduce the viscosity.

[0023] US 2023 / 0301750 Al (Richter et al.) describes a heating device for heating a dental material and a method for controlling the temperature of a dental material.

[0024] WO 2024 / 057265 Al (Solventum) describes a heating device for heating a dental material, the heating device comprising a housing comprising a wall and a top opening formed within the wall and a heating element at least partially received through the top opening of the housing, the heating element comprising a base and a pyramidal portion extending from the base in a direction away from the top opening of the housing.

[0025] WO 2021 / 053408 Al (3M) describes a heating device for heating a dental material. The heating device has a body and a socket. The socket is removably received within the body and has a socket wall that forms a receptacle for positioning a container for the dental material therein. The body has a light source for emitting light toward the socket wall in a direction toward the receptacle. The socket wall is at least partially transmissive for infrared light.

[0026] US 11,730,566 B2 (Frontein et al.) describes a method for treating a dental material comprising the steps of providing a device comprising a radiation-curable dental material in a first temperature range, and irradiating the provided device with radiation of a second wavelength, preferably with IR light of a wavelength in the range of 600 nm to 50,000 nm, in order to heat the dental material and reduce the viscosity of the dental material by means of heating to a desired viscosity or less.

[0027] EP 1 151 728 Al (Friedman) describes a method and a heating assembly for enhancing the cure of photocurable dental restorative composites containing unreactive monomers and filler upon exposure to light radiation characterized by preheating the photocurable dental restorative composites to an elevated temperature above ambient prior to said exposure to light radiation during clinical usage.

[0028] Another approach which was suggested is the application of ultrasound.

[0029] US 2011 / 0143303 Al (Da Rold Marco et al.) describes a vibrating applicator for applying a dental composite material onto a tooth. The applicator has an elongated body and a tip that is coupled to the elongated body to apply the dental composite material onto the tooth. The applicator further has a vibrating apparatus for vibrating the tip and a sensor for sensing a condition of the dental composite material. A controller is operatively coupled to the vibrating apparatus and to the sensor and is configured to automatically vary an output frequency of the vibrating apparatus in response to the condition sensed by the sensor.

[0030] However, none of these options is fully satisfying.

[0031] Using a screw tube for dispensing a dental composite material into a small tooth cavity is not really possible. The screw tube is too large and the amount of dental composite material to be dispensed cannot be adequately controlled. Furthermore, two hands are needed if a screw tube is used that has a smaller outlet bore than inner cartridge diameter. If the outlet diameter is as large as the inner cartridge diameter, it is not suitable to fill a smaller cavity.

[0032] Using an applier for dispensing a dental composite material from a dental capsule may reduce the force needed during the dispensing process, but due to the size of the applier the application process is still cumbersome. And the disinfection of the applier is an additional working step.

[0033] Using a dental capsule with a larger opening of the dispensing nozzle may reduce the force needed for the application of the dental composite material, as well, but does not really allow the precise application of a small quantity of material. Reducing the viscosity by applying ultrasound typically only works for a time period where the ultrasound is applied. This only can be achieved by using an expensive applier with an inbuilt ultrasound generator. Furthermore, the use of capsule appliers typically reduces the visual access to the dental cavity.

[0034] Reducing the viscosity by applying heat usually works only for a small amount of material as it has to be ensured that all of the dental composite material which is needed is adequately and homogeneously heated to the desired temperature.

[0035] Further, in particular the repeated application of heat on a dental composite material may have a negative impact on the properties of the remaining dental composite material stored in the application device. In particular the shelf life may be negatively affected. of Invention

[0036] Thus, there is still a desire for a multidose delivery and application device for dental composite materials that can be used for applying the dental composite material directly into the tooth cavity of a patient to be treated without the need of an additional applier.

[0037] Ideally, the dispensing of the dental composite material from the application device should be easily possible.

[0038] One or more of the above-mentioned objects are addressed by the invention described in the present text and claims.

[0039] According to one aspect the invention is directed to a process for of warming a dental composite material, the process comprising the steps of inserting an application device having the shape of a syringe into an opening of a heating device, the application device comprising a compartment having a proximal end, a distal end, an inner surface, an inner diameter and an axial length Lc, a piston assembly with a proximal end and a distal end, the piston assembly being moveably located in the compartment, a dispensing section with a nozzle located at the distal end of the compartment having an opening in the range of 1.5 to less than 3 mm in diameter, the dispensing section being an integral part of the application device, a backplate section located at the proximal end of the compartment, a pressure plate located at the proximal end of the piston assembly, the dental composite material being located in the compartment of the application device, the dental composite material having a viscosity in the range of 5 to 20 kPa*s at 23°C, the heating device comprising a housing with an opening for receiving the application device, a heating element, a temperature sensor, a controller, warming the dental composite material located in the compartment of the application device up to a temperature not higher than 70°C, as described in the present text and claims.

[0040] A further aspect the invention is directed to a kit of parts comprising a heating device, at least one application device containing a dental composite material, an instruction for use outlining a process of warming the dental composite material, wherein the heating device, the application device, the dental composite material and the process of warming are as described in the present text and claims.

[0041] Unless defined differently, for this description the following terms shall have the given meaning: “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.

[0042] “Distal” means the opposite of proximal. For a syringe assembly, the front or dispensing end is the distal end of the syringe assembly.

[0043] “Section” means a portion or area of an assembly or device.

[0044] 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.

[0045] 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.

[0046] A ’’dental composite material” is a dental material intended for restoring a defect tooth, in particular for filling a tooth cavity. Dental composite materials usually have a high filler load (e.g. above 70 wt.%) and also show a high viscosity.

[0047] As used herein, "(meth)acryl" is a shorthand term referring to "acryl" and / or "methacryl”. For example, a "(meth) acryloxy" group is a shorthand term referring to either an acryloxy group (i.e., CH2=CH-C(O)-O-) and / or a methacryloxy group (i.e., CH2=C(CH3)-C(O)-O-). 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.

[0048] The terms “warming” and “heating” are used interchangeably and refer to an increase of temperature of a subject.

[0049] “Configured to” is at least as restrictive as “adapted to” and requires actual design intention to perform the specific function rather than mere physical capability of performing such a function.

[0050] ''Controller" refers to one or more microcomputers, processors, application-specific integrated circuits, or any other suitable programmable circuit or combination of circuits.

[0051] “Ambient conditions” mean the conditions which the composition described in the present text is usually subjected to during storage and handling. Ambient conditions may, for example, be a pressure of 900 to 1,100 mbar, a temperature of 10 to 40 °C and a relative humidity of 10 to 100 %. In the laboratory ambient conditions are typically adjusted to 20 to 25 °C and 1,000 to 1,025 mbar (at maritime level).

[0052] 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.).

[0053] 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.).

[0054] 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”.

[0055] 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’.

[0056] Fig. 1 shows an embodiment of the application device for use in the process described in the present text.

[0057] Fig. 2 shows an application device having been inserted in the opening of a heating device.

[0058] Fig. 3 shows a cross-sectional view of an embodiment of the application device.

[0059] It has been found that the process and the respective compositions and devices as described in the present text are advantageous for a couple of reasons.

[0060] The application device comprises a backplate section and a pressure plate which enables the practitioner to handle the application device like a normal syringe.

[0061] The shape of the application device allows for a reliable warming of the dental composite material stored in the compartment of the application device.

[0062] Further, the slim size and shape of the application device allows for a reasonable fast heating of the dental composite material on the one hand and for storing a larger amount of dental composite material on the other hand and thus allowing a so-called multi-dose application treatment.

[0063] There is also no need for an additional attachment or socket which is usually needed for ensuring an adequate heat transmission from the heating elements of the heating device to the outer surface of the application device.

[0064] Further, due to the presence of a nozzle at the dispensing section the dispensing and application of the dental composite material to a tooth surface in the mouth of a patient to be treated is more convenient and more precise.

[0065] After warming, the extrusion force needed for dispensing the dental composite material from the compartment is reduced to an acceptable and convenient level for the practitioner.

[0066] Thus, the dental composite material can be dispensed without the need for an additional mechanical dispensing device, such as caulking gun.

[0067] Further, the shape of the application device does not require the whole compartment of the application device to be heated, the heating of only a portion thereof is often sufficient.

[0068] It was surprisingly found that the dental composite material can already be dispensed from the application device if only the front portion of the compartment is heated.

[0069] This can be beneficial since dental composite materials are typically limited in the time they withstand elevated temperatures. Thus, a repeated heating of a dental composite material is usually to be avoided.

[0070] This is because a repeated heating and / or heating to a higher temperature may cause “stress” in the dental composite material or cause an undesired degradation of the dental composite material which may have a negative impact on the desired physical properties later.

[0071] The invention relates to a process of warming a dental composite material.

[0072] This process comprises the steps of inserting an application device containing a dental composite material into an opening of a heating device, and warming the dental composite material up to a temperature not higher than 70°C or not higher than 65°C. The warmed dental composite material then has a reduced viscosity which enables the dispensing of the material from the application device with less extrusion forces.

[0073] It turned out that is already sufficient if only a portion of the dental composite material is heated, e.g. the warming of the dental composite material only over a length of not more than 30% of the axial length Lc of the compartment.

[0074] This can be achieved, e.g. if the application device is inserted into the opening of the heating device over a length of not more than 30% of the axial length Lc of the compartment.

[0075] To avoid an undesired so-called “stressing” of the dental composite material, the warming is typically done for not longer than 10 min or not longer than 8 min or not longer than 5 min. It can already be sufficient, if the warming is done for only 1 to 3 min.

[0076] It was found that such a shortened time period for an adequate heating step can be achieved, if the ratio of axial length of the compartment to inner diameter of the compartment is in the range of 80 / 3 to 40 / 8.

[0077] A thin wall thickness of the compartment may further contribute to a shortened time period for the heating step as the heat transfer from the heating elements of the heating device to the dental composite material becomes more efficient.

[0078] The application device described in the present text comprises a compartment, a piston assembly, a dispensing section with a nozzle, a backplate section and a pressure plate.

[0079] 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.

[0080] The compartment is cylindrical and typically tube-shaped.

[0081] The compartment comprises an inner surface and an outer surface.

[0082] The compartment can be characterized by having a proximal end, a distal end, an inner diameter and an axial length.

[0083] The length and diameter of the compartment essentially defines the volume of the application device which is available for receiving the dental material to be stored.

[0084] The volume of the compartment is typically within a range of 0.4 ml to 5 ml.

[0085] The inner diameter of the compartment is typically within the range of 3 to 8 mm or 3 to 5 mm.

[0086] The outer diameter of the compartment is typically within the range of 4 to 10 mm or 4 to 8 mm.

[0087] The wall thickness of the compartment is typically within the range of 0.5 to 2 mm.

[0088] The ratio of axial length of the compartment to inner diameter of the compartment is typically in the range of 80 / 3 to 40 / 8. That is, the compartment typically has the shape of a small lengthy tube. 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. Further, it was found that such a shape is advantageous for ensuring an effective heat transfer from the heat elements of the heating device to the dental composite material and also allows for the warming of only a portion of the dental composite material stored in the compartment.

[0089] The compartment comprises a dispensing section through which the dental composite material can be dispensed.

[0090] The dispensing section is located at the distal end of the compartment.

[0091] The dispensing section is an integral part of the application device. That is, the dispensing section cannot be simply separated from the compartment or exchanged by another dispensing element. Both parts, the compartment and the dispensing section are made out of the same material.

[0092] The dispensing section comprises a dispensing nozzle.

[0093] The dispensing section may comprise a curved nozzle or may comprise a tapered nozzle oriented from the distal end of the compartment in an angle of 30 to 60° with respect to the axial length of the compartment.

[0094] If present, the tapered section of the nozzle may comprise a conical inner surface.

[0095] The opening of the dispensing section is less than 3 mm or up to 2.5 mm or up to 2 mm. The opening of the dispensing section is typically in a range of 1.5 to less than 3 mm.

[0096] The ratio of the opening of the nozzle to the inner diameter of the compartment is typically in a range of 2 / 8 to less than 3 / 3 or in a range of 2 / 8 to 2.5 / 3.

[0097] Such a ratio was found to be beneficial as the opening is small enough for allowing a precise application of the dental composite material to a dental situation in the mouth of a patient but large enough from an extrusion force perspective of view.

[0098] If desired, the opening of the nozzle may be protected by a removable cap.

[0099] Within the compartment, in particular at the rear or proximal end of the compartment, a piston assembly is inserted, which is in sliding engagement with the inner surface of the compartment. That is, the piston assembly is movable within the compartment.

[0100] The piston assembly is also for partially sealing the rear end of the compartment and may have means of venting air when seating the piston into the compartment after filling the dental composite material.

[0101] The piston assembly typically comprises a piston body, which typically has a cylindrical shape.

[0102] During use of the application device, the front end of the piston body is in contact with the dental composite material stored in the compartment.

[0103] The piston further may comprise a piston rod.

[0104] The piston rod is connected to or is attachable to the proximal end of the piston body.

[0105] Once attached to the piston assembly, the piston rod should remain in its attached position to the piston body during use of the application device. If desired, the piston assembly and the piston rod can be made of one part. Thus, both parts, the piston body and the piston rod can be sections of one single plunger.

[0106] A pressure plate is located at the proximal end of the piston assembly.

[0107] The pressure plate typically forms an integral part of the piston rod.

[0108] The pressure plate is for receiving pressure exerted by the practitioner during use of the application device. The pressure is typically exerted by a thumb of the practitioner.

[0109] The shape of the pressure plate is not particularly limited.

[0110] For design reasons, the shape of the pressure plate may be similar to the shape of the backplate section.

[0111] The backplate section of the application device typically comprises a flat surface area in proximal direction.

[0112] The backplate section also comprises an opening for a piston rod.

[0113] In proximal direction, the backplate section may be shaped circular, elliptical, quadratic, rectangular, or triangular wherein the comers may be rounded.

[0114] For good handling purposes, a triangular shape can be advantageous.

[0115] The backplate section usually functions as a finger plate section.

[0116] Further, the backplate section may comprise a seal Al surrounding the opening in the backplate section in the direction to the piston rod.

[0117] Seal Al is for sealing the opening in the backplate section to the piston rod.

[0118] Seal Al comprised by the backplate section of the application device does typically not exceed the flat surface area of the backplate section.

[0119] That is, the proximal surface of seal Al and the flat surface area of the backplate section typically form a uniform surface without grooves or recesses.

[0120] Seal Al is typically a liquid-tight seal, preferably in the form of a lip seal, but not an air-tight seal.

[0121] The heating device described in the present text comprises a housing, a heating element and a temperature sensor. The heating device also comprises a controller.

[0122] The housing is configmed to house the components of the heating device, such as electronics, power supply, controller, etc. The housing can be of a one-piece construction or a multi-piece construction.

[0123] The housing of the heating device comprises one or more (e.g. at least 2 or at least 3 or least 4) openings for receiving one or more application devices. The openings are top openings formed within the wall of the housing. A heating device with more than one opening allows for the simultaneous or sequential heating of different application devices which may comprise dental composite materials with different chemical compositions and / or color.

[0124] The diameter of the opening is typically in the range of 5 to 15 mm and is thus rather small.

[0125] The opening can extend through the housing by a certain distance, e.g. a length of up to 15 cm, up to 10 cm or up to 5 cm.

[0126] The heating elements of the heating device may comprise the following elements alone or in combination: one or more infrared LEDs; an electrically heatable metal block.

[0127] Infrared light is defined as light having a wavelength in the range of 800 nm to 1500 nm, in particular in the range of 850 to 1,000 nm. The light power of the LEDs is typically in the range of 5 to 20 W or 10 to 18 W.

[0128] Using infrared LEDs can be advantageous as they exhibit a minimized heat capacity so that the LEDs cool down almost immediately after deactivation.

[0129] Suitable materials for the metal block comprise aluminium, copper, etc.

[0130] The temperature sensor is for determining temperature and ensuring that the temperature of the dental composite material during the warming step does not exceed the desired temperature. The temperature sensor is adjusted to the desired temperature (e.g. 70°C or less).

[0131] Suitable temperature sensors include a thermistor, IR temperature sensor, thermophile, thermocouple, or a resistance temperature detector (RTD).

[0132] The temperature sensor is typically communicably coupled to the controller.

[0133] The controller is typically adapted to interrupt the heating operation upon receiving a signal from the temperature sensor. The controller can be configured to limit the heating of the dental composite material to more than 70°C.

[0134] Typically, the temperature of the outer surface of the compartment of the application device is determined. The temperature of the outer surface of the compartment is an indicator for the temperature of the dental composite material stored in the compartment.

[0135] The heating device may further comprise a timer function for activating and automatically deactivating the heating operation after a predefined time.

[0136] If infrared LEDs are used as heating elements, a predefined time may be in the range of 5 to 30 s, or 10 to 20 s.

[0137] The heating device may further comprise a rechargeable battery for powering the heating element. This would allow the operating of the heating device in a wireless manner. The heating device may further be connectable to an external power source for recharging the battery. Suitable heating devices which can generally be used are also described in the following references, which are herewith incorporated by reference: WO 2021 / 053408 Al (3M), WO 2024 / 057265 Al (Solventum), US 2023 / 301750 Al (3M).

[0138] The application device described in the present text is intended for storing and dispensing a dental composite material.

[0139] The dental composite material is located in the compartment of the application device.

[0140] The dental composite material is typically a curable material, in particular a radiation-curable material, and may comprise polymerizable components, in particular polymerizable components comprising ethylenically unsaturated groups, such a (meth)acrylate moieties.

[0141] The dental composite material typically comprises filler. The filler is typically present in an amount of at least 70 wt.% with respect to the weight of the dental composite material.

[0142] The dental composite material may further comprise an initiator suitable for curing the polymerizable components.

[0143] Compared to other dental materials, a dental composite material has a high viscosity, which is in the range of 5 to 20 kPa*s at 23°C.

[0144] Further or alternative embodiments of the invention are described below.

[0145] Embodiment 1

[0146] The process as described in the present text characterized by the following features: the warming of the dental composite material being done for no longer than 10 min, the application device being inserted into the opening of the heating device over a length of not more than 30% of the axial length Lc of the compartment, the volume of the compartment being in the range of 1 to 5 ml, the dispensing section comprising either a curved nozzle, or a tapered nozzle oriented from the distal end of the compartment in an angle of 30 to 60° with respect to the axial length of the compartment, the process not comprising the use of a dispensing device in addition to the application device, the dental composite material located in the compartment of the application device being warmed without using a further attachment.

[0147] Embodiment 2

[0148] The process as described in the present text characterized by the following features: the warming of the dental composite material being done for no longer than 10 min, the application device being inserted into the opening of the heating device over a length of not more than 30% of the axial length Lc of the compartment, the volume of the compartment being in the range of 1 to 5 ml, the dispensing section comprising a tapered nozzle oriented from the distal end of the compartment in an angle of 30 to 60° with respect to the axial length of the compartment, the process not comprising the use of a dispensing device in addition to the application device, the dental composite material located in the compartment of the application device being warmed without using a further socket, the application device not comprising a lubrication layer on the inner surface of the compartment.

[0149] Embodiment 3

[0150] The process as described in the present text characterized by the following features: the warming of the dental composite material being done for no longer than 10 min, the warming of the dental composite material being done only over a length of not more than 30% of the axial length Lc of the compartment, the application device being inserted into the opening of the heating device over a length of not more than 30% of the axial length Lc of the compartment, the volume of the compartment being in the range of 1 to 5 ml, the dispensing section comprising either a curved nozzle, or a tapered nozzle oriented from the distal end of the compartment in an angle of 30 to 60° with respect to the axial length of the compartment, the process not comprising the use of a dispensing device in addition to the application device, the dental composite material located in the compartment of the application device being warmed without using a further attachment.

[0151] Embodiment 4

[0152] The process as described in the present text characterized by the following features: the warming of the dental composite material being done for no longer than 10 min, the warming of the dental composite material being done only over a length of not more than 30% of the axial length Lc of the compartment, the application device being inserted into the opening of the heating device over a length of not more than 30% of the axial length Lc of the compartment, the volume of the compartment being in the range of 1 to 5 ml, the dispensing section comprising either a curved nozzle, or a tapered nozzle oriented from the distal end of the compartment in an angle of 30 to 60° with respect to the axial length of the compartment, the ratio of axial length of the compartment to inner diameter of the compartment being in a range of 80 / 3 to 40 / 8, the process not comprising the use of a dispensing device in addition to the application device. It was found that the dental composite material located in the compartment of the application device can be warmed without using a further socket or receptacle when inserting the application device into the opening of the heating device.

[0153] In the prior art such a socket or element is often recommended to ensure a proper alignment of the application device in the heating device and / or for improving the heat transfer from the heating elements to the dental material.

[0154] Further, it was found that the inner surface of the compartment of the application device does not need to comprise a lubrication layer, which may help to reduce the friction between the dental composite material and the inner wall of the compartment.

[0155] There is also typically no need for a further dispensing device (such as a caulk gun) in addition to the application device.

[0156] It was found that after warming the dental composite material can already be dispensed from the application device by simply exerting pressure on the pressure plate located at the proximal end of the piston assembly of the application device.

[0157] The application device described in the present text is not for applying materials intramuscular or intravenous of a human being.

[0158] Similarly, the application device is not for sampling body fluids (e.g., blood) from a human being. Further, the outer surface of the compartment of the application device does typically not comprise grooves or ridges. Due to the absence of grooves and / or ridges the compartment is easier to clean.

[0159] In addition, the outer surface of the compartment does typically not comprise a label containing information about the dental material to be stored or dispensed from the application device.

[0160] Due to the absence of a label which is typically adhesively fixed to the outer surface of the compartment, the risk that the label is detached during use and / or during a disinfecting step becomes zero. Further, due to the absence of a label the heat transfer during the warming step is not negatively affected.

[0161] The application device itself and its parts are typically produced by injection-moulding. Alternatively, the application device and its parts can be produced by 3d-printing.

[0162] The application device and its individual parts are typically made out of plastic, preferably materials which can be injection moulded.

[0163] The material the application device and / or its parts are made of is typically selected from PP (polypropylene), PE (polyethylene), PA (polyamide), PBT (polybutadiene terephthalate), PET (polyethylene terephthalate), COC (cycloolefin-copolymer).

[0164] To prevent an undesired curing of the material stored in the application device, 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). The material of the application device may also form a light filter which provides a first transmittance of light within a first wavelength range, and a second transmittance of light within a second wavelength range, wherein the first transmittance is below 5% over the first wavelength range, the second transmittance is above 20% over the second wavelength range, with the second wavelength range at least partially covering the wavelength range of visible light, and wherein the first and second wavelength ranges are each within the spectrum of visible light ranging from about 380 nm to about 750 nm; see e.g., US 9,498,309 B2 (Boehm et al.).

[0165] If desired and for further protecting the material from light during storage, the application device can comprise a removable cap at the dispensing section.

[0166] The production and / or assembly of the application device 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 placing of the dental material can be done at a different location.

[0167] According to one embodiment, the application device is assembled out of the following individual parts: the piston body, the piston rod, the pressure plate, the compartment with the backplate section and the nozzle, the optional cap for sealing the nozzle.

[0168] The invention also relates to a kit of part comprising the heating device as described in any of the preceding claims, at least one application device containing a dental composite material, and an instruction for use outlining a process of warming the dental composite material, wherein the heating device, the application device, the dental composite material and the process of warming are as described in the present text and claims.

[0169] Described is also a method of using the application device for treating a dental situation in the mouth of a patient.

[0170] The method typically comprises the following steps: applying at least a portion of the dental composite material being located or stored in the compartment of the application device to the dental situation to be treated, applying radiation to the applied portion of the dental material.

[0171] The following description of the figures is given to illustrate the invention.

[0172] Reference signs and possible and preferred ranges or dimensions of the application device are further described in the table below.

[0173] Fig. 1 shows an embodiment of the application device for use in the process described in the present text.

[0174] The application device comprises a compartment (20) with a dispensing section (30) and a backplate section (40). The dispensing section (30) comprises a nozzle (31), the opening of which is protected by a cap (32).

[0175] The backplate section (40) comprises a plate (42), which may be a used for labelling. Plate (42) and the proximal surface of the backplate section (40) form a flat surface area.

[0176] The application device further comprises a piston assembly comprising a piston body (not shown) and a piston rod (80) which is partially inserted into the compartment (20) through an opening (41) in plate (45).

[0177] The piston assembly further comprises a pressure plate (90).

[0178] Fig. 2 shows an application device (10) having been inserted in one opening (210) of a heating device. The compartment of the application device has only been inserted to about 1 / 3 of the axial length of the compartment Lc. In this embodiment, the heating device comprises 6 openings (210). The heating device further contains a housing (220), heating element (not shown), a temperature sensor (not shown) and a controller (not shown).

[0179] Fig. 3 shows a cross-sectional view of an embodiment of the application device.

[0180] The application device (10) comprises a compartment (20) which contains a dental composite material (100) and portions of the piston assembly (60).

[0181] The compartment has a distal end (21) and a proximal end (22), an outer surface (23) and an inner surface (24)

[0182] The application device (10) further comprises a backplate section (40) into which a plate (42) with a flat surface is inserted.

[0183] The piston assembly comprises a piston rod (80) to which is attached in proximal direction a pressure plate (90). In distal direction of the piston rod (80) there is located a piston body (70) which is hollow. In distal direction the piston body (70) is in contact with a dental composite material (100). Shown is also a nozzle (31) at the dispensing section.

[0184] The above specification, examples and data provide a description of the manufacture and use of the compositions and methods of the invention.

[0185] 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.

[0186] 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 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 of thereof.

[0187] The following examples are given to illustrate the invention.

[0188] Methods

[0189] Extrusion Force

[0190] 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 (application device with material stored therein) 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 material from the application device at ambient conditions (23°C). During this process the applied force is recorded.

[0191] Viscosity

[0192] If desired, viscosity can be measured using a Physica MCR 301 Rheometer (Anton Paar, Graz, Austria) with a plate / plate geometry under controlled shear rate at 23 °C. The diameter is 15 mm, the separation gap between the plates 0.5 mm. The shear rate is ramped from 1,000 s'1to 0.001 s’1. Determination of Temperature

[0193] If desired, the warming of the dental composite material can be determined by using a commercially available non-contact temperature measuring devices (e.g. a device measuring the infrared radiation).

Claims

Claims1. A process of warming a dental composite material, the process comprising the steps of inserting an application device having the shape of a syringe into an opening of a heating device, the application device comprising a compartment having a proximal end, a distal end, an inner surface, an inner diameter and an axial length Lc, a piston assembly with a proximal end and a distal end, the piston assembly being moveably located in the compartment, a dispensing section with a nozzle located at the distal end of the compartment having an opening in the range of 1.5 to less than 3 mm in diameter, the dispensing section being an integral part of the application device, a backplate section located at the proximal end of the compartment, a pressure plate located at the proximal end of the piston assembly, the dental composite material being located in the compartment of the application device, the dental composite material having a viscosity in the range of 5 to 20 kPa*s at 23°C, the heating device comprising a housing with an opening for receiving the application device, a heating element, a temperature sensor, a controller, warming the dental composite material located in the compartment of the application device up to a temperature not higher than 70°C.

2. The process according to any of the preceding claims, wherein the warming of the dental composite material is done only over a length of not more than 30% of the axial length Lc of the compartment.

3. The process according to any of the preceding claims, wherein the application device is inserted into the opening of the heating device over a length of not more than 30% of the axial length Lc of the compartment.

4. The process according to any of the preceding claims, wherein the warming of the dental composite material is done for no longer than 10 min.

5. The process according to any of the preceding claims, the dispensing section comprising either a curved nozzle, or a tapered nozzle oriented from the distal end of the compartment in an angle of 30 to 60° with respect to the axial length of the compartment.

6. The process according to any of the preceding claims, the ratio of the opening of the nozzle to the inner diameter of the compartment being in a range of 2 / 8 to less than 3 / 3.

7. The process according to any of the preceding claims, the compartment of the application device being characterized by the following features alone or in combination: volume: 0.4 to 5 ml, wall thickness: 0.5 to 2 mm.

8. The process according to any of the preceding claims, the ratio of axial length of the compartment to inner diameter of the compartment being in the range of 80 / 3 to 40 / 8.

9. The process according to any of the preceding claims, the dental composite material being characterized by the following features alone or in combination: comprising hardenable components, preferably (meth)acrylates components, comprising filler, preferably in an amount of at least 70 wt.% with respect to the weight of the dental composite material, comprising an initiator system suitable for curing the hardenable components of the dental composite material, preferably by radiation.

10. The process according to any of the preceding claims, the heating device being characterized by the following features alone or in combination: comprising at least 2 openings for the application device, the diameter of the opening being in the range of 5 to 15 mm.

11. The process according to any of the preceding claims, the heating elements of the heating device comprising the following elements alone or in combination: an infrared LED, an electrically heatable metal block.

12. The process according to any of the preceding claims, wherein the dental composite material located in the compartment of the application device is warmed without using a further socket.

13. The process according to any of the preceding claims not comprising the use of an applier in addition to the application device.

14. The process according to any of the preceding claims characterized by the following features: the warming of the dental composite material being done for no longer than 10 min, the application device being inserted into the opening of the heating device over a length of not more than 30% of the axial length Lc of the compartment, the volume of the compartment being in the range of 1 to 5 ml, the dispensing section comprising either a curved nozzle, or a tapered nozzle oriented from the distal end of the compartment in an angle of 30 to 60° with respect to the axial length of the compartment, the process not comprising the use of a dispensing device in addition to the application device, the dental composite material located in the compartment of the application device being warmed without using a further socket.

15. A kit of parts comprising the heating device as described in any of the preceding claims, at least one application device containing a dental composite material, an instruction for use outlining a process of warming the dental composite material, the heating device, the application device, the dental composite material and the process of warming being as described in any of the preceding claims.

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