Two-part dental sealant, method of application with syringe device, and kit

Abstract

The invention relates to a two-part dental sealant, a method of application with a syringe device, and a kit. Specifically, the present invention provides a method of administering a two-part dental sealant, the method comprising providing a syringe device (1) comprising a cartridge (10) comprising a first chamber and a second chamber. The first chamber comprises a first portion of a dental sealant comprising a (meth) acrylate resin and an oxidation curing agent. The second chamber comprises a second portion of the dental sealant comprising a (meth) acrylate resin and a reducing curing agent that reacts with the oxidizing curing agent of the first chamber. The first portion and / or the second portion of the dental sealant further comprise a single component or components that neutralize acids and promote remineralization. The syringe device comprises a dispensing nozzle (17) comprising a static mixer and an outlet at one end of the cartridge and a plunger (20) at the opposite end of the cartridge. A kit for storing and applying a dental sealant is also described.

Description

[0001] This invention patent application is a divisional application of the invention patent application with international application number PCT / IB2019 / 054644, international application date of June 4, 2019, application number 201980037224.0 which entered the Chinese national phase, and the invention title "Two-part dental sealant, method of application by syringe device and kit". Technical Field

[0002] This invention relates to two-part dental sealants, methods of application using a syringe device, and kits. Specifically, the invention provides a method of applying a two-part dental sealant, the method comprising providing a syringe device (1) including a cartridge (10) comprising a first chamber and a second chamber. The first chamber contains a first portion of the dental sealant comprising (meth)acrylate resin and an oxidizing curing agent. The second chamber contains a second portion of the dental sealant comprising (meth)acrylate resin and a reducing curing agent reacting with the oxidizing curing agent of the first chamber. The first and / or second portions of the dental sealant also contain a single component or multiple components that neutralize acid and promote remineralization. The syringe device includes a dispensing nozzle (17) and a plunger (20), the dispensing nozzle including a static mixer and an outlet located at one end of the cartridge, the plunger located at the opposite end of the cartridge. The invention also describes kits for storing and applying dental sealants. Background Technology

[0003] Sealant is commonly used to prevent tooth decay caused by the buildup of caries-causing microorganisms in a patient's dentition. The areas of the dentition most suitable for sealant treatment are those commonly referred to as pits and fissures. Sealant fills these pits and fissures to achieve a smooth morphology, thus preventing microbial buildup without impairing chewing ability.

[0004] Conventional dental sealants are provided as transparent compositions or compositions containing opaque fillers to impart a white finish. For example, US 4,150,012 discloses a dental composition made of a two-part system, wherein each of the two parts comprises a polymerizable resin and an opaque filler; however, the first container contains a catalyst, and the second container contains an accelerator that reacts with the catalyst in the first container. The dental material is chemically cured (via a redox reaction) and provides an opaque dental material upon curing.

[0005] As another example of dental sealant, US 6,444,725 discloses an aesthetic dental sealant comprising a curable resin, a hardener, and a colorant, wherein the composition has an initial color before being exposed to photochemical irradiation and a final color (e.g., a tooth-like color) different from the initial color after the composition is exposed to photochemical irradiation. Summary of the Invention

[0006] While color application can facilitate accurate application of dental sealants, the industry has found the following methods of applying dental sealants to have advantages: minimizing sealant waste, shortening sealant processing time, and providing other beneficial effects.

[0007] In one embodiment, a method of applying a two-part dental sealant is described. The method includes providing a syringe device comprising a cartridge including a first chamber and a second chamber. The first chamber contains a first portion of the dental sealant comprising (meth)acrylate resin and an oxidizing curing agent. The second chamber contains a second portion of the dental sealant comprising (meth)acrylate resin and a reducing curing agent that reacts with the oxidizing curing agent in the first chamber. The first and / or second portions of the dental sealant also contain a single component or multiple components that neutralize acid and promote remineralization. The syringe device includes a dispensing nozzle and a plunger. The dispensing nozzle includes a static mixer and an outlet located at one end of the cartridge, and the plunger is located at the opposite end of the cartridge. The plunger includes two rods, wherein one end of the rods seals the first and second portions of the dental sealant within the chamber, and the opposite ends of the plunger rods are connected. The method includes manually applying pressure to the plunger to deliver the first and second portions of the dental sealant onto the tooth surface through the static mixer and the outlet of the dispensing nozzle.

[0008] In another embodiment, a kit for storing and applying dental sealant is described, the kit comprising: i) a syringe device including: a) a cartridge comprising a first chamber and a second chamber, The first chamber contains (meth)acrylate resin and an oxidizing curing agent, and The second chamber contains (meth)acrylate resin and a reducing curing agent that reacts with the oxidizing curing agent in the first chamber, and the first and / or second chambers also contain a single or multiple components that neutralize acid and promote remineralization; b) a plunger located at one end of the cartridge, wherein the plunger includes two rods, one end of which seals a first and a second portion of the dental sealant within the chamber, and the opposite ends of the plunger rods are connected. The kit also includes: ii) At least one removable dispensing nozzle, the at least one removable dispensing nozzle comprising a static mixer attached to the opposite end of the cartridge.

[0009] In another embodiment, a two-part dental sealant composition is described, the composition comprising: The first part comprises (meth)acrylate resin and an oxidizing curing agent; and the second chamber part comprises (meth)acrylate resin and a reducing curing agent that reacts with the oxidizing curing agent of the first chamber; wherein the first part and the second part each have a viscosity of not more than 5000 cps, and the two-part dental sealant composition further comprises a single component or multiple components that neutralize acid and promote remineralization. Attached Figure Description

[0010] Figure 1 This is a perspective view of an illustrative syringe; Figure 2 This is a cross-sectional view of an illustrative syringe; Figure 3 This is a cross-sectional view of an illustrative syringe; (referring to US2016 / 0270879) Figure 3 (Variations) Figure 4 This is a side view of an illustrative static mixer. (WO 2016 / 205181) Figure 2 –FN76390) Detailed Implementation

[0011] The present invention describes: a method for applying dental sealant using a syringe device; a kit for storing and applying dental sealant, the kit including a syringe device for receiving two portions of dental sealant and a removable dispensing nozzle attached to the syringe device; and a two-part dental sealant composition.

[0012] Figure 1 An exemplary syringe device 1 suitable for dispensing two portions of dental sealant material is shown. The syringe device includes, for example, a cylindrical cartridge 10, a plunger 20, and a dispensing nozzle 17.

[0013] The cartridge 10 typically has a cylindrical external shape. In a typical embodiment, the cartridge also includes a finger plate 113. The finger plate 113 is shaped to include a flat portion or support point, which prevents the cartridge 10 from tipping over when placed on a flat surface. Thus, when the syringe 1 is placed on a flat surface such as a table, the flat portion of the finger plate 113 of the cartridge 10 prevents the syringe from rolling off the table.

[0014] The syringe 1 cartridge 10 is pre-filled with a two-component dental sealant. One portion of the two-component dental sealant is contained in a first chamber 111, and the second portion of the two-component dental sealant is contained in a second chamber 112.

[0015] like Figure 2As best shown in the cross-sectional view, the syringe 1 has a plunger 20 including a first plunger rod 121 and a second plunger rod 122. One end of each rod 121, 122 is configured to seal a first portion and a second portion of dental sealant within chambers 111 and 112. Opposite ends of the plunger rods are connected at the rear end 16 of the syringe 20.

[0016] The cartridge contains a sufficient amount of two-component dental sealant for sealing one or more teeth. Typically, the amount of two-component dental sealant is sufficient to seal all teeth in a single patient. In some embodiments, the amount of two-component dental sealant is sufficient to seal all teeth in more than one patient, and a removable nozzle is interchanged between patients. In a typical embodiment, the manufacturer pre-fills the syringe with the two-part dental sealant composition. In some embodiments, the (e.g., pre-filled) syringe, the two-part dental sealant composition, and one or more removable dispensing nozzles are packaged into a kit for storing and applying the dental sealant. The kit typically also includes instructions for using the kit and attaching the removable nozzle to the syringe.

[0017] To facilitate use in the oral cavity and minimize waste of dental sealant, the syringe device is relatively small. In some implementations, such as Figure 1 and Figure 2 As shown, the total length of the filled syringe (without nozzle) before engagement with the plunger is no greater than 200 mm, 190 mm, 180 mm, 170 mm, 160 mm, 150 mm, or 140 mm. The total length of the filled syringe (without nozzle) is typically at least 100 mm, 110 mm, 120 mm, or 130 mm. In some embodiments, the total length of the cartridge is typically no greater than 100 mm, 95 mm, 90 mm, 85 mm, 80 mm, or 75 mm. The total length of the cartridge is typically at least 50 mm, 55 mm, 60 mm, or 65 mm. The length of the inner chamber is less than the total length of the cartridge. In some embodiments, the total length of the inner chamber is no greater than 70 mm or 65 mm. The outer diameter of the cartridge is typically no greater than 15 mm, 14 mm, 13 mm, 12 mm, 11 mm, 10 mm, 9 mm, or 8 mm. The outer diameter is typically at least 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, or 7.5 mm. The total internal volume of the cartridge is usually no more than 5cc, 4.5cc, 4cc, 3.5cc, 3cc or 2.5cc.

[0018] In a typical implementation, the first chamber and the second chamber have a volume ratio of approximately 1:1. Other volume ratios may be used. For example, the chamber volume ratio may range from 1:1 to approximately 2:1 or 3:1.

[0019] When the first and second parts are intended to be mixed in a 1:1 volume ratio, the first and second chambers contain approximately half the total volume of the cartridge. Therefore, the total internal volume of each chamber is typically no greater than 2.5cc, 2cc, 1.75cc, 1.5cc, or 1.25cc.

[0020] Figure 3 A cross-sectional view of the syringe 1 passing through the cartridge 10 is shown. The cartridge 10 has two chambers 111, 112 extending through it. In some embodiments, these chambers have a substantially D-shaped cross-section, such as the D-shaped cross-section described in U.S. Patent Publication No. 2016 / 0270879, which is incorporated herein by reference.

[0021] Specifically, the D-shaped perimeter is defined solely by a plurality of circular segments 19a, 19b, 19c, and 19d. (Circular segments 19a, 19b, 19c, and 19d correspond to the first, third, second, and fourth circular segments, respectively.) The circular segment 19a adjacent to the partition wall has a radius different from that of the opposing circular segment 19c adjacent to the outer wall 17. Specifically, circular segment 19a has a larger radius than circular segment 19c. Thus, in one respect, a substantially D-shaped cross-section is achieved, but a more reliable seal is achieved with a cross-section based solely on circular structures compared to a cross-section having one or more straight structures. Furthermore, the circular segments 19a, 19b, 19c, and 19d are joined in such a manner that at the joint of two circular segments, the corresponding tangents passing through the joint on each circular segment coincide. Or, in other words, the circular segments 19a, 19b, 19c, and 19d smoothly merge with each other and together form a closed line defining the perimeter of the cross-section.

[0022] In a preferred embodiment, the radius of the first circular segment can be in the range of 10mm to 20mm, 10mm to 30mm, 10mm to 40mm, or 10mm to 50mm; the radius of the second circular segment can be in the range of 2mm to 5mm, 2mm to 10mm, 2mm to 15mm, or 2mm to 20mm; and the radii of the third and fourth circular segments can be in the range of 0.3mm to 1mm, 0.3mm to 2mm, or 0.3mm to 3mm. In one embodiment, radius 19a is about 14mm, radius 19b is about 1mm, and radius 19c is about 4mm.

[0023] As shown in the figure, two substantially D-shaped cartridges are arranged in a mirror image of each other, such that the cartridge 10 has a generally cylindrical external shape at one end and an outer wall 117 with a partition wall 118 having a substantially uniform wall thickness at the other end. The substantially uniform wall thickness is advantageous for manufacturing the cartridge, for example, by injection molding (e.g., polypropylene).

[0024] In some embodiments, each of plunger rods 121 and 122 is configured for press-fitting into a corresponding chamber of the cartridge. The plunger rod may comprise a material more rigid than the cartridge. In some embodiments, the plunger rod is injection-molded from polypropylene containing 50% glass fiber. The cross-sectional shape of each plunger rod generally corresponds to the cross-sectional shape of the corresponding chamber. Thus, when the chamber has a substantially D-shaped cross-section, the plunger rod also has a substantially D-shaped cross-section.

[0025] In some embodiments, the end portions of the plunger rods 121 and 122 that seal the two portions of dental sealant within the chamber are preferably oversized relative to the cross-sectional shape of the respective chamber, specifically by being expanded in two dimensions through offset. In one embodiment, each plunger rod 121 and 122 has a skirt-type lip seal, as described in more detail in previously cited U.S. Patent Publication No. 2016 / 0270879.

[0026] The chamber and plunger rod can have a variety of other designs and cross-sectional shapes, so that the two-component dental sealant is sealed in the corresponding chamber before use.

[0027] The dispensing nozzle 17 is removably attached to the front end 15 of the cartridge 10. In some embodiments, the nozzle is rotatably attached to the front end of the cartridge 10. The cartridge, nozzle, or a combination thereof includes a valve that provides or blocks fluid communication between the two portions of dental sealant in the cartridge 10 and the dispensing nozzle 17. In some embodiments, the cartridge 10 and nozzle 17 are combined to form a rotary slide valve. Further details regarding the valve are described in WO2018 / 057503 and US 9,427,290; these patents are incorporated herein by reference.

[0028] The dispensing nozzle 17 also includes a cannula 172, which includes a static mixer 40 ( Figure 1 Not shown in the image, but... Figure 2 and Figure 4 (Drawn in the middle).

[0029] The volume and design are selected to maximize mixing and minimize waste. In some embodiments, without a static mixer, the total volume of the dispensing nozzle is typically no greater than 0.25 cc, 0.20 cc, 0.15 cc, or 0.10 cc. In some embodiments, the total volume of the dispensing nozzle is no greater than 0.09 cc, 0.08 cc, 0.07 cc, 0.06 cc, 0.05 cc, 0.04 cc, or 0.03 cc. The cannula has an external width of 2 mm, 2.5 mm, or 3 mm and a length of approximately 75 mm to 150 mm.

[0030] Various static mixers can be used. Figure 4 It shows that it can be arranged in Figure 1 and Figure 2 An illustrative example is a preferred static mixer 40 within a dispensing nozzle. Such static mixers are described in WO2015 / 205181; this patent is incorporated herein by reference. The static mixer 40 has cascaded mixing elements 41a / 41b. Each mixing element 41a / 41b is based on a helical or spiral shape. The structure of such a helical mixing element can be essentially conceived as a planar sheet of material fixed at opposite ends twisted or rolled 180 degrees, although such structures are typically manufactured using other methods (e.g., injection molding). The overall external shape of such mixing elements 41a / 41b is based on a cylindrical helix. Thus, each mixing element has an outer diameter D. Each mixing element has an inlet edge 42a / 42b and an outlet edge 43a / 43b for the material. Regarding the flow F of dental material through the mixing unit, the material enters each mixing element 41a / 41b at the inlet edge 42a / 42b and exits each mixing element 41a / 41b at the outlet edge 43a / 43b. The static mixer 40 has a plurality of mixing elements 41a / 41b arranged in sequence. The inlet edges 42a / 42b and outlet edges 43a / 43b of two adjacent mixing elements 41a / 41b are offset at an angle relative to each other. Therefore, as dental material flows through the mixing unit 40, the flow of the two components of the dental material is separated and its partial diversions are merged multiple times. Thus, the dental material (e.g., its two parts) is mixed. The offset angle between the inlet edges 42a / 42b and the outlet edges 43a / 43b is measured in a plane perpendicular to the longitudinal axis A of the mixing unit and at a point on that longitudinal axis. In this example, the offset angle between the inlet edges 42a / 42b and the outlet edges 43a / 43b is 90 degrees. In other words, the inlet edges 42a / 42b and the outlet edges 43a / 43b of adjacent mixing elements 41a / 41b are arranged intersecting each other.

[0031] As shown in the figure, the mixing unit 40 has right-handed mixing elements 41a and left-handed mixing elements 41b arranged in an alternating sequence along the longitudinal axis A. The right-handed mixing elements 41a and left-handed mixing elements 41b differ in the winding direction of the helix on which the mixing elements 41a / 41b are based.

[0032] In some embodiments, the mixing elements 41a / 41b have an outer diameter D between 1.5 mm and 1.6 mm. Additionally, each mixing element has a length L between 0.6 mm and 1.2 mm, preferably 0.78 mm. The diameter D and length L are preferably the same for all mixing elements 41a / 41b of the mixing unit 40. A specific range of diameter D for the mixing elements 41a / 41b can provide improved mixing.

[0033] The dispensing nozzle head 173 can be rigid or flexible. It can be formed of a thermoplastic material or can be a hollow metal needle. In some embodiments, the nozzle head of the dispensing nozzle is angled, extending from the cannula at an internal angle ranging from 90° to 180°. In some embodiments, the internal angle is at least 95°, 100°, 105°, or 110°. In some embodiments, the internal angle is not greater than 170°, 160°, 150°, 140°, or 130°. In some embodiments, the length of the nozzle head can be in the range of about 5 mm to 15 mm or 5 mm to 20 mm. In some embodiments, the length of the nozzle head is not greater than 14 mm, 13 mm, 12 mm, 11 mm, or 10 mm. The outlet is typically circular, having a narrower diameter than the cannula. In some implementations, the diameter of the outlet is at least 0.5 mm, 0.6 mm, 0.7 mm or 0.8 mm, and up to 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm or 1.5 mm.

[0034] The syringe 1 may optionally include an actuator for progressively engaging the plunger toward the tip of the syringe. Including an actuator is useful for dispensing a predetermined amount (e.g., a single dose) of dental sealant material. This feature allows for the precise application of the correct amount—enough to fill pits and fissures—rather than an excessive amount that would make the presence of the hardened sealant noticeable to the patient during chewing. An example of a syringe with an actuator is further described in WO2017 / 180545; that patent is incorporated herein by reference.

[0035] During use of the syringe device, the nozzle is rotated to open the slide valve, allowing the fluid contained within the chamber to be delivered through the nozzle. Fingers (e.g., index and middle fingers) contact the finger plate 113, and the thumb typically presses against the rear end 16 of the plunger, causing the first plunger rod 121 and the second plunger rod 122 to move toward the front end 15 of the syringe device. Pressure is applied to the rear end of the plunger by hand, thereby delivering a first and second portion of the dental sealant to the tooth surface (e.g., enamel) through the static mixer and outlet.

[0036] The two components are combined with each other by merging in a static mixer. When measured according to the test method described in the embodiments, each of the components preferably has a viscosity of no more than 5,000 cps at 23°C. In some embodiments, the viscosity of each of the components is no more than 4,500 cps, 4,000 cps, 3,500 cps, or 3,000 cps at 23°C. The viscosity of each of the components is typically at least 200 cps, 300 cps, 400 cps, or 500 cps at 23°C.

[0037] Furthermore, the viscosities of the two components are typically similar, for example, differing by no more than 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10% of the viscosity of the material with higher viscosity. When the viscosity and viscosity difference of each component to be mixed are within a suitable range, a sufficiently homogeneous mixture can be dispensed through the outlet. Additionally, the components can be conveyed through a static mixer at relatively low extrusion forces. Such low extrusion forces can typically be generated by a manual operating system.

[0038] In some embodiments, the method of applying a dental sealant also includes conditioning the tooth surface prior to the application of the sealant. Such conditioning may include, for example, acid etching, priming, abrasion, or a combination thereof; as is known in the art.

[0039] Each component of a dental sealant contains a polymerizable resin. The polymerizable resin is typically a mixture of (meth)acrylate monomers. A common acrylic monomer is described in U.S. Patent No. 3,066,112. This type of acrylic monomer is the product of the reaction of bisphenol A or other bisphenols with glycidyl methacrylate, a reaction product commonly referred to in the art as a Bis-GMA monomer. Typically, this monomer is combined with various other monomers (e.g., lower molecular weight, lower viscosity) such as di(meth)acrylate monomers (e.g., tetraethylene glycol dimethacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, etc.) or monofunctional (meth)acrylate monomers (e.g., methyl methacrylate).

[0040] The dental sealants described herein comprise a "redox" curing system. In a redox process, a reducing agent loses electrons and is oxidized, while an oxidizing agent gains electrons and is reduced. The combination of the oxidizing and reducing agents results in the generation of initiating substances (such as free radicals or cations) capable of causing the curable resin to cure (e.g., polymerize and / or crosslink). Typically, the redox pair is activated at temperatures below approximately 40°C.

[0041] Suitable oxidizing agents include peroxide compounds (i.e., peroxy compounds), including hydrogen peroxide, as well as inorganic and organic peroxide compounds (e.g., "peroxy" compounds or salts having a peroxide anion). Examples of suitable oxidizing agents include, but are not limited to: peroxides such as benzoyl peroxide, phthaloyl peroxide, substituted benzoyl peroxide, acetyl peroxide, hexanoyl peroxide, lauroyl peroxide, cinnamoyl peroxide, acetylbenzoyl peroxide, methyl ethyl ketone peroxide, sodium peroxide, hydrogen peroxide, di-tert-butyl peroxide, tetrahydronaphthalene peroxide, urea peroxide, and cumene peroxide; and hydroperoxides such as p-methane hydroperoxide, diisopropylbenzene hydroperoxide, tert-butyl hydroperoxide, methyl ethyl ketone hydroperoxide, and 1-hydroxycyclohexyl hydroperoxide-1.

[0042] Other oxidizing compounds include persulfate compounds (such as ammonium persulfate and potassium persulfate), perborate compounds (such as sodium perborate), perchlorate compounds (such as sodium perchlorate), ozone, ozonides, etc. These oxidants can be used alone or in combination with each other.

[0043] One or more oxidizing agents may be present in the first initiator system in an amount sufficient to provide initiation of the hardening process and the desired curing rate. Based on the total weight of all components of the dental material, dental sealants typically contain at least 0.01 wt%, 0.02 wt%, 0.03 wt%, 0.04 wt%, 0.05 wt%, 0.06 wt%, 0.07 wt%, 0.08 wt%, 0.09 wt%, or 1 wt%, and up to 5 wt%, 5.5 wt%, 6 wt%, 6.5 wt%, 7 wt%, 7.5 wt%, 8 wt%, 8.5 wt%, 9 wt%, 9.5 wt%, or 10 wt% of an oxidizing curing agent. In some embodiments, the dental sealant contains at least 1.5 wt%, 2.0 wt%, 2.5 wt%, 3.0 wt%, 3.5 wt%, 4.0 wt%, 4.5 wt%, or 5 wt% of an oxidizing curing agent.

[0044] The first initiator system also includes a reducing agent having one or more functional groups for activating the oxidant and initiating hardening. These functional groups are typically selected from amines, thiols, or mixtures thereof. If more than one functional group is present, they may be provided as part of the same compound or by different compounds.

[0045] The preferred reducing agent is a tertiary aromatic amine. Examples of usable tertiary amines are:

[0046] Each R group may be H or an organic group that does not adversely affect the initiation of hardening of dental materials. This organic group generally does not sterically or electronically impede the function of the reducing agent. Examples of such compounds are disclosed in WO 97 / 35916, published on October 2, 1997.

[0047] Preferably, R 1 It is an aliphatic group, and R 2 and R 3 Independently comprised (i.e., they may be the same or different) H, aromatic, and / or aliphatic groups (preferably comprising up to 20 carbon atoms). Preferably, R 2 and R 3 Only one of them is an aromatic group. More preferably, R 1 An alkyl group optionally substituted with a hydroxyl group (preferably comprising up to 10 carbon atoms), and R 2 and R 3It is H or an alkyl group optionally substituted with a hydroxyl group (preferably comprising up to 10 carbon atoms). For certain preferred embodiments, R 1 R 2 and R 3 It may also include polymerizable functional groups that react with the functional groups of the resin. Preferably, R 1 R 2 and R 3 At least one of them contains a functional group such as acrylate, methacrylate, acrylamide, vinyl, or other functional groups present in the above resin.

[0048] Preferably, R 4 R 5 R 6 R 7 and R 8 Independently, it is an H or aliphatic group (preferably comprising up to 20 carbon atoms). More preferably, R 4 R 5 R 6 R 7 and R 8 Independently H or an alkyl group optionally substituted with a hydroxyl group (preferably comprising up to 10 carbon atoms). For certain preferred embodiments, R 4 R 5 R 6 R 7 and R 8 It may also include polymerizable functional groups that react with the functional groups of the resin. Preferably, R 4 R 5 R 6 R 7 and R 8 At least one of them contains a functional group such as acrylate, methacrylate, acrylamide, vinyl, or other functional groups present in the above resin.

[0049] Particularly preferred tertiary aromatic amines are N,N-bis(2-hydroxyethyl)-p-toluidine (DHEPT), 2-(4-dimethylaminophenyl)ethanol (DMAPE), and 4-tert-butyldimethylaniline. Other suitable compounds include DMAPEs derived from: difunctional or polyfunctional acid compounds, such as adipic acid, sebacic acid, 1,3,5-benzenetricarboxylic acid, 1,2,4,5-benzenetetracarboxylic acid, etc.; or DMAPEs having difunctional or polyfunctional isocyanates, such as hexamethylene diisocyanate, isoflurane diisocyanate, and "desmodur N-330" (trifunctional isocyanate).

[0050] Tertiary amines may be polymerizable. Particularly preferred polymerizable aromatic tertiary amines include, but are not limited to: adducts of IEM (isocyanoethyl 2-methacrylate) and N,N-bis(2-hydroxyethyl)-p-toluidine (DHEPT-di-IEM or bis-N,N-[2-(2-methacryloyloxyethylaminocarbonyloxy)ethyl]-p-toluidine), adducts of DMAPE and VDM (2-vinyl-4,4-dimethylacrylonitrile) (DMAPE-VDM or 4-[2-(2-acrylamido-2-methylpropionyloxy)ethyl)-N,N-dimethylaniline), adducts of methacrylate diester and DHEPT (DHEPT-diester or bis-N,N-(2-methacryloyloxyethyl)-p-toluidine), and adducts of DHEPT and VDM (DHEPT-di-VDM or bis-N,N-[2-(2-acrylamido-2-methylpropionyloxy)ethyl]-p-toluidine).

[0051] Another preferred reducing agent is a thiol, which may include aromatic and / or aliphatic groups and optionally polymerizable groups. Preferred thiols have a molecular weight greater than about 200 because they have a mild odor. Particularly preferred thiols are isooctyl mercaptoacetate (IOTG) and pentaerythritol tetra(3-mercaptopropionate) (PETMP).

[0052] Tertiary amines and thiols can be used alone or in combination with each other. For example, a first initiator system may contain one tertiary aromatic amine and one thiols, two tertiary aromatic amines, two thiols, a polymerizable tertiary aromatic amine, etc. Other reducing agents such as sulfinic acid, formic acid, ascorbic acid, hydrazine, and their salts may also be used herein to initiate free radical polymerization. However, preferably, the first initiator system comprises tertiary amines, thiols, or mixtures thereof. Such reducing agents can be used as components of both the first and second initiator systems.

[0053] When using two or more reducing agents, they are preferably selected such that at least one reducing agent has a faster activation rate than the others.

[0054] One or more reducing agents may be present in the first initiator system in an amount sufficient to provide initiation of the hardening process and the desired curing rate. Based on the total weight of all components of the dental material, dental sealants typically contain at least 0.01 wt%, 0.02 wt%, 0.03 wt%, 0.04 wt%, 0.05 wt%, 0.06 wt%, 0.07 wt%, 0.08 wt%, 0.09 wt%, or 1 wt%, ranging up to 5 wt%, 5.5 wt%, 6 wt%, 6.5 wt%, 7 wt%, 7.5 wt%, 8 wt%, 8.5 wt%, 9 wt%, 9.5 wt%, or 10 wt% of reducing curing agent. In some embodiments, dental sealants contain at least 1.5 wt%, 2.0 wt%, 2.5 wt%, 3.0 wt%, 3.5 wt%, 4.0 wt%, 4.5 wt%, or 5 wt% of reducing curing agent.

[0055] Small amounts of transition metal compounds can also be added to accelerate the redox curing rate. In some embodiments, the dental sealant preferably contains a secondary ionic salt to enhance the stability of the polymerizable composition, as described in U.S. Patent Publication No. 2003 / 0195273 (Mitra et al.). The concentrations of the oxidizing and reducing curing agents are selected to provide the optimal reaction rate. If the reaction rate is too fast, the dental sealant may cure prematurely in the dispensing nozzle. If the reaction rate is too slow, the total processing time may be prolonged. In some embodiments, the dental sealant cures within 5 minutes, 4 minutes, 3 minutes, 2 minutes, or 1 minute.

[0056] Dental sealants may also include a second initiator system. The second initiator system comprises one or more initiators commonly used in free radical polymerization reactions. The second initiator is preferably a free radical photoinitiator, which can be activated upon irradiation with photochemical radiation (using conventional dental curing light) to initiate the polymerization (or curing) of the free radical polymerizable composition.

[0057] When exposed to light energy with wavelengths between 400 nm and 800 nm, photoinitiators typically generate free radicals for addition polymerization reactions. When dental sealants are photocured by conventional dental curing light, the sealants may also contain rose red or other photobleachable colorants, such that the dental sealant is colored before curing, and the teeth are colored after curing, as described in US 6,444,726, which is incorporated herein by reference. A variety of photoinitiators suitable for dental compositions are known.

[0058] In some implementations, dental sealants also contain sensitizers. These sensitizers can be co-initiated by amine reducing agents.

[0059] Ideally, the sensitizer should be soluble in the monomer and exhibit absorbance in the wavelength range of greater than 400 nm to 800 nm, more preferably from 400 nm to about 500 nm. The sensitizer can also sensitize 2-methyl-4,6-bis(trichloromethyl)-s-triazine using the test procedure described in U.S. Patent 3,729,313, which is incorporated herein by reference. Preferably, in addition to passing this test, the sensitizer may also be selected in part based on storage stability considerations.

[0060] In addition to the colors imparted by dyes or pigments, sensitizers can also impart light-bleachable colors. For example, camphorquinone can impart a yellow color to the material of this invention, and rose red can impart a pale red color to the material.

[0061] Suitable sensitizers may include compounds from the following categories: ketones, coumarin dyes (e.g., coumarin ketones), xanthracene dyes, fluorescent ketone acridine dyes, triazole dyes, thiazole dyes, thiazine dyes, oxazine dyes, acridine dyes, aminoketone dyes, porphyrins, aromatic polycyclic aromatic hydrocarbons, para-substituted aminostyryl ketone compounds, aminotriarylmethanes, cyanine, squaric acid dyes, and pyridine dyes. Xanthracene dyes include those with molecular structures related to xanthracene and color index values ​​ranging from 45,000 to 45,999. Ketones (e.g., monoketones or α-diketones), coumarin ketones, amino aromatic ketones, and para-substituted aminostyryl ketone compounds are preferred sensitizers. For applications requiring high sensitivity, sensitizers containing an ajulolidinyl moiety are preferred.

[0062] For example, preferred categories of ketone sensitizers have the following formula: ACO(X) b B Suitable ketones with the above chemical formulas include monoketones (b=0), such as 2,2-dihydroxybenzophenone, 4,4-dihydroxybenzophenone or 2,4-dihydroxybenzophenone, di-2-pyridyl-ketone, di-2-furanyl ketone, di-2-phenylthioketone, benzoin, fluorenone, chalcone, michle ketone, 2-fluoro-9-fluorenone, 2-chlorothioxanthone, acetophenone, benzophenone, 1- or 2-naphthyl acetophenone, 9-acetylanthracene, 2-acetylphenanthrene, 3-acetylphenanthrene or 9-acetylphenanthrene, 4-biphenylacetophenone, acetophenone, n-phenylbutanone, phenylpentanone, 2-acetylpyridine, 3-acetylpyridine or 4-acetylpyridine, 3-acetylcoumarin, etc. Suitable diketones include aralkyl diketones, such as anthraquinone, phenanthrenequinone, o-diacetylbenzene, m-diacetylbenzene and p-diacetylbenzene, 1,3-diacetylnaphthalene, 1,4-diacetylnaphthalene, 1,5-diacetylnaphthalene, 1,6-diacetylnaphthalene, 1,7-diacetylnaphthalene and 1,8-diacetylnaphthalene, 1,5-diacetylanthracene, 1,8-diacetylanthracene and 9,10-diacetylanthracene, etc. Suitable α-diketone compounds (b=1 and X=CO) include 2,3-butanedione, 2,3-pentanedione, 2,3-hexanedione, 3,4-hexanedione, 2,3-heptanedione, 3,4-heptanedione, 2,3-octanedione, 4,5-octanedione, biphenyl, 2,2'-dihydroxybiphenyl, 3,3'-dihydroxybiphenyl and 4,4'-dihydroxybiphenyl, furozyloyl, di-3,3'-indolylethyldione, 2,3-camphenedione (camphorquinone), diacetyl, 1,2-cyclohexyldione, 1,2-naphthoquinone, acetylnaphthoquinone, etc.

[0063] Dental sealants (e.g., their first and / or second portions) also contain materials that promote remineralization, such as materials that release calcium ions, phosphorus ions (e.g., phosphates), fluoride ions, or combinations thereof. In some embodiments, the dental sealant also contains a calcium-releasing compound, such as calcium salts. Examples of calcium salts include calcium glycerophosphate, calcium carbonate, calcium chloride, calcium butyrate, calcium citrate, calcium gluconate, calcium gluconate, calcium hydroxide, calcium hydroxyapatite, calcium lactate, calcium oxalate, calcium oxide, calcium pantothenate, calcium phosphate, calcium polycarboxylate, calcium propionate, calcium pyrophosphate, and calcium sulfate. In some embodiments, such as with calcium oxide, the calcium-releasing compound also neutralizes acid. Thus, a single component promotes remineralization and neutralizes acid. In other embodiments, the calcium-releasing compound does not neutralize acid. In this embodiment, the dental sealant also contains a separate component that is an alkaline material.

[0064] In some embodiments, dental sealants contain materials that promote remineralization by releasing fluoride ions, such as AlF3, Na2AlF3, and mixtures thereof. Other fluoride-releasing components include silanol-treated fluoroaluminosilicate glass fillers, such as those described in U.S. Patent No. 5,332,429. Sources of organofluorine compounds are also suitable, such as those described in U.S. Patent No. 4,871,786.

[0065] In some implementations, dental sealants contain materials that promote remineralization by releasing phosphorus ions. Suitable phosphorus compounds include P₂O₅, AlPO₄, and mixtures thereof. Some salts, such as calcium glycerophosphate, release both calcium and phosphorus ions.

[0066] The concentration of such components that promote remineralization is typically at least 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5% of the total dental sealant, and generally not more than about 10% by weight. However, higher concentrations may be used when the components that promote remineralization also neutralize the acid.

[0067] The first and / or second part of a dental sealant also contains an alkaline component to neutralize acids. In the case of dental sealants, it is presumed that the alkaline component can neutralize acids originating from bacteria or food sources that come into contact with the cured dental sealant.

[0068] The neutralizing acid component is typically combined with (e.g., the second) portion of a dental sealant containing a polymerizable resin and a reduction curing agent.

[0069] In an advantageous embodiment, the dental sealant comprises an encapsulating material comprising a chemically alkaline core material. In one advantageous embodiment, an inorganic shell material surrounds the core. The shell material and shell thickness can be selected to allow controlled and / or delayed release or reaction of the alkaline core material. In some embodiments, the release of the alkaline core material is intended to increase alkalinity after a delayed period of time. Such encapsulating materials are further described in U.S. Patent Publication No. 2017 / 063829; that patent is incorporated herein by reference.

[0070] Alternatively, dental sealants may contain unencapsulated alkaline chemical materials. Therefore, the following description of "alkaline core" also applies to unencapsulated "alkaline materials".

[0071] Encapsulating fillers comprise a basic core material. The basic (e.g., core) material, as well as the material forming the core (e.g., a compound), is typically solid at 25°C. The basic (e.g., core) material can be a single particle or multiple smaller associated particles. As used herein, the term "associated" refers to a collection of two or more primary particles that are aggregated and / or agglomerated. Similarly, the term "non-associated" refers to a collection of two or more primary particles that are not aggregated and / or agglomerated.

[0072] In some implementations, the basic (e.g., core) material may comprise multiple aggregated particles. The term "aggregate" or "aggregated" refers to strong association between primary particles. For example, primary particles may be chemically bonded to each other. The breakdown of aggregates into smaller particles (e.g., primary particles) typically does not occur during the manufacture and encapsulation of the basic (e.g., core) material, thus keeping the aggregated basic (e.g., core) particles as aggregates. Similarly, the term "non-aggregated" refers to primary particles that do not exhibit strong association with other primary particles.

[0073] In other embodiments, the basic (e.g., core) material may comprise multiple agglomerated particles. As used herein, the term "agglomerated" or "agglomerated" refers to weak association between primary particles. For example, primary particles may be held together by charge or polarity. The agglomeration may break down into smaller particles (e.g., primary particles) during the manufacture and encapsulation of the basic (e.g., core) material. Similarly, the term "non-agglomerated" refers to primary particles that do not exhibit weak association with other primary particles.

[0074] The average (e.g., primary, associated, or agglomerated) particle size of the alkaline (e.g., core) material is typically at least 0.2 micrometers, 0.5 micrometers, 1 micrometer, 2 micrometers, 3 micrometers, 4 micrometers, or 5 micrometers, and typically no greater than 1 mm, 750 micrometers, or 500 micrometers, as measured using, for example, a sedimentation analyzer. In some embodiments, the average (e.g., primary, associated, or agglomerated) particle size of the alkaline (e.g., core) material is typically no greater than 250 micrometers, 200 micrometers, 150 micrometers, 100 micrometers, or 50 micrometers. In some embodiments, the average (e.g., primary, associated, or agglomerated) particle size of the alkaline (e.g., core) material is typically no greater than 45 micrometers, 40 micrometers, 35 micrometers, 30 micrometers, 25 micrometers, or 20 micrometers. Because the shell is typically thin, the encapsulating material may also fall within the average particle size just described.

[0075] The core material is alkaline. Chemically alkaline materials are those that donate electrons, accept protons, and typically provide hydroxyl ions in aqueous solutions.

[0076] A material comprising a core having or exhibiting one or more of the following properties: including containing a sufficient amount of a high pKa component, providing an alkaline pH when added to deionized water (as described in further examples) or providing an alkaline pH when added to an acid buffer (as described in further examples), is considered alkaline.

[0077] Basic materials are used to react with acids and acidic buffer solutions, thereby increasing the pH. The change in pH and the rate of pH change depend on the strength of the basic component, the chemical and physical forms of the basic component, and the amount of the basic component within the basic (e.g., core) material.

[0078] In some embodiments, the basic material (e.g., the core of the encapsulated material) is strongly basic. Strongly basic materials include, and are prepared from, sufficient amounts of strongly basic materials (e.g., compounds) that typically have a pKa in the range of about 11-14. Examples of strongly basic compounds include oxides and hydroxides of alkali metals and alkaline earth metals, as well as strongly basic salts such as alkali metal phosphates. Specific examples of strongly basic (e.g., core) compounds include: oxides and hydroxides of Na, K, Ca, Sr, and Ba; silicates of Na, K, Ca, Sr, and Ba; and aluminates of Na, K, Ca, Sr, and Ba. Based on cation molarity, strongly basic silicates and glasses typically contain at least 1, 2, or 3 moles of a strongly basic (e.g., core) compound (e.g., CaO) per mole of silica. Similarly, based on cation molarity, strongly basic aluminates typically contain at least 1, 2, or 3 moles of a strongly basic (e.g., core) compound (e.g., CaO) per mole of aluminate.

[0079] In some embodiments, the strongly basic material may be a heterogeneous physical mixture of at least one strongly basic compound and a less basic or neutral material. For example, the strongly basic material may be a physical mixture of silica and sodium hydroxide. Sodium hydroxide is a strongly basic material having a pKa of 13.8. A 0.1N aqueous solution of sodium hydroxide has a pH of 13. By weight percentage, one gram of a mixture of 96 wt% silica and 4 wt% sodium hydroxide in one liter of water will provide a 0.1N aqueous solution of sodium hydroxide. When the encapsulating material is a physical mixture, substantially all of the strongly basic compound is accessible during shell degradation. Therefore, in this embodiment, the basic (e.g., core) material may contain a small amount (e.g., at least 1 wt%, 2 wt%, or 3 wt%) of strongly basic material to provide a delayed pH of at least 8.5 or 9 in deionized water (according to the test method described in the examples). However, higher concentrations of chemically basic (e.g., core) materials may be required to provide a delayed pH of at least 8.5 or 9 in acidic buffer solutions. For example, depending on the pKa of the strong base material, the amount of the strong base material can be 5%, 6%, 7%, 8%, 9%, or 10% of the total encapsulated material.

[0080] In other embodiments, the basic material (e.g., the core of the encapsulated material) is a multi-component crystalline compound comprising and prepared from at least one strongly basic material (e.g., a compound) and other components (such as alkaline earth metal silicates). In other embodiments, the basic material (e.g., the core of the encapsulated material) may be characterized as a multi-component amorphous glass prepared from at least one strongly basic material (e.g., a compound). The strongly basic material (e.g., the compound) may be uniformly or non-uniformly distributed in the glass structure. When the basic material (e.g., the core of the encapsulated material) is a molten multi-component material such as glass, the concentration of the strongly basic compound (which can be determined by X-ray fluorescence (XRF) or inductively coupled plasma (ICP)) is typically at least 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, or 50 wt%, ranging up to 75 wt% or greater, based on the total basic (e.g., core) material.

[0081] In some advantageous embodiments, the basic (e.g., core) material comprises and is prepared from CaO with a pKa of 11.6. CaO can be used to provide both a delayed increase in pH and a source of calcium ions. The amount of CaO is typically at least 5 wt%, 10 wt%, 15 wt%, 20 wt%, or 25 wt%, and the amount of Ca can be about 71% of such values ​​in a range of up to 75 wt% or greater. Specific examples of strongly basic multi-component (e.g., core) materials containing CaO include: Portland binder (reported to contain 60 wt% to 70 wt% CaO); tricalcium silicate (containing about 75 wt% CaO); and bioactive glass, such as that available from 3M Advanced Material Division (containing about 25 wt% CaO and about 25 wt% Na2O).

[0082] In other embodiments, the basic material (e.g., the core of the encapsulated material) is weakly basic. The weakly basic material comprises at least one material (e.g., a compound) having a significant amount of at least one pKa in the range of at least 8 but less than 11. In some embodiments, the weakly basic material has a pKa of at least 8.5, 9, 9.5, 10, or 10.5. Examples of weakly basic (e.g., core) compounds include oxides of Cu, Zn, and Fe, as well as weakly basic salts such as NaF, calcium acetate, and hydrogen phosphate.

[0083] Alternatively, the weakly basic (e.g., core) material may contain a small amount of a strongly basic compound or be prepared therefrom. A weakly basic (e.g., core) material alone typically cannot provide sufficient hydroxyl ions to adequately increase the pH of an acidic solution. However, a weakly basic (e.g., core) material alone can provide sufficient hydroxyl ions to adequately increase the pH of water. Furthermore, (e.g., encapsulated) weakly basic (e.g., core) materials may be used in combination with (e.g., encapsulated) strongly basic (e.g., core) materials.

[0084] (For example, encapsulated) alkaline materials are generally not reducing agents in redox curing systems. Encapsulation of the reducing agent will delay the redox curing reaction. Furthermore, since the reducing agent is usually a weak base used in relatively low concentrations, encapsulated reducing agent alone will not provide the desired pH increase.

[0085] In an advantageous embodiment, the basic (e.g., core) material further comprises and is prepared from one or more neutral compounds defined herein as having a pKa of at least 6, 6.5, or 7 and less than 8. In some embodiments, such neutral compounds exhibit low solubility in deionized water, and / or weak acid solutions, and / or weak base solutions. Weak acid solutions typically have a pH less than 7 but greater than 4. Weak base solutions typically have a pH greater than 7 but less than 10. Low solubility is defined as dissolving in less than 100 g / L (i.e., 10% by weight). In some embodiments, dissolving in less than 50 g, 25 g, 5 g, or 1 g per liter. Neutral compounds include, for example, silica, zirconium oxide, titanium dioxide, alumina, and combinations thereof. While a pKa greater than 7 indicates slightly basicity, such basicity is less than that of weakly basic (e.g., core) materials and significantly less than that of strongly basic (e.g., core) materials as described above.

[0086] When a (e.g., core) material contains an alkaline material (e.g., a compound or a combination of an alkaline and neutral material) and is prepared solely from it, the alkalinity of the (e.g., core) material can be estimated based on the weight of that component. Thus, as previously stated, the (e.g., core) material contains a certain amount of an alkaline material (e.g., a compound). However, when the core material also contains an acidic material (e.g., a compound), estimating the alkalinity can be more difficult. Especially for embodiments where it is difficult to estimate the alkalinity of the (e.g., core) material based on its composition or compositional analysis, the alkalinity of the alkaline (e.g., core) material or encapsulated core material can be defined by the pH change of a specified amount of the material in deionized water or an acidic (e.g., buffer solution). These tests can also be used to verify that the (e.g., core) material or encapsulated core material is indeed alkaline.

[0087] For example, fluoroaluminosilicate (FAS) glass is a homogeneous glass structure prepared from approximately 19% by weight of a strongly basic compound (SrO), with the remainder prepared from neutral (SiO2) and other compounds. When tested in deionized water, FAS glass lowers the pH to 6.5 within 15 minutes according to the test method described in previously cited 78772, and is therefore considered a weakly acidic core material.

[0088] In some implementations, the alkalinity of the (e.g., core) material or encapsulated core material can be determined by the pH change of a specified amount (0.25 g) of material in 25 g of deionized water. Unencapsulated alkaline (e.g., core) materials typically change the pH of deionized water from neutral to at least 8.5 or 9. This typically occurs within 1 minute, 2 minutes, 3 minutes, 4 minutes, or 5 minutes, but can take up to an hour or 24 hours.

[0089] In an advantageous embodiment, the alkalinity of the alkaline (e.g., core) material or encapsulating material can be determined by the pH change of a specified amount (0.25 g) of the material in a buffer solution having a pH of 4 (e.g., buffer solution BDH5018), which is a solution of 15 g of deionized water and 10 g of aqueous potassium hydrogen phthalate buffer solution adjusted to pH 4.00 (with hydrochloric acid) at 25°C. This test is referred to herein as a “buffer test.” When a strongly alkaline (e.g., core) material or encapsulating material undergoes a buffer test, it can also reach a pH of at least 8.5 or 9. It should be understood that a larger amount of hydroxyl ions is required to change an acidic solution to an alkaline pH compared to deionized water. Therefore, this pH change can take longer compared to the same material in deionized water. In some embodiments, such a pH change occurs within 5 minutes, 10 minutes, or 15 minutes, but may require 1 hour or 24 hours.

[0090] When tested according to a buffering test, a weakly basic material (e.g., the core) can provide a small increase in pH. For example, the pH can change from 4 to 5. However, when tested according to a buffering test, a weakly basic material (e.g., the core) does not provide enough hydroxyl ions to achieve a pH of at least 8.5 or 9.

[0091] Therefore, when the encapsulated alkaline core material is initially added to the water or buffer solution (i.e., immediately after the material is immersed in water or a buffer solution), it does not change the pH, but the pH subsequently increases at different rates depending on the shell and the alkaline core material.

[0092] In some implementations, the alkaline (e.g., core) material is curable or self-curing when mixed with water, such as in the case of various neutral and synthetic adhesives. Conventional natural adhesives (e.g., Portland) and synthetic adhesives typically contain a large amount of calcium silicate (e.g., 3CaO-SiO2, 2CaO-SiO2), alone or in combination with one or more calcium aluminates (e.g., 3CaO-Al2O3, 4CaO-Al2O3-Fe2O3).

[0093] In some implementations, the encapsulating material is an encapsulating (e.g., dental) filler.

[0094] Encapsulation (e.g., dental) fillers may contain a significant amount of neutral metal oxides having low solubility in water or acidic solutions with a pH of 3-4, as previously described. Neutral metal oxides include, for example, silica, zirconium oxide, titanium dioxide, and alumina. The amount of neutral metal oxide may be at least 10%, 15%, 20%, 25%, or 30% by weight of the total weight of the alkaline (e.g., core) material, ranging up to 50%, 60%, 70%, 80%, or 90% by weight. Calcium silicate and encapsulated calcium silicate may also be characterized as fillers due to their silica content.

[0095] Dental sealants contain materials that promote remineralization, as previously described. These materials may be present in the core of an encapsulated filler, provided as a second filler such as FAS glass, or provided as a separate component in a hardenable dental sealant composition.

[0096] In some embodiments, the core or second filler material comprises and is prepared from a fluoride compound (such as AlF3, Na2AlF3, and mixtures thereof), the amount of which is in the range of about 5% by weight to 40% by weight. In some embodiments, the amount of AlF3 is in the range of 10% by weight to 30% by weight of the core or second filler material. In some embodiments, Na2AlF3 is in the range of 2% by weight to 10% by weight of the core or second filler material.

[0097] In some embodiments, the core or second filler material comprises phosphides such as P2O5, AlPO4, and mixtures thereof, in an amount ranging from 2% to 25% by weight. In some embodiments, the amount of P2O5 ranges from 2% to 15% by weight in the core or second filler material. In some embodiments, the amount of AlPO4 ranges from 2% to 10% by weight in the core or second filler material.

[0098] Basic (e.g., core) materials can be encapsulated using any suitable method. In some embodiments, basic (e.g., core) materials can be encapsulated in an inorganic shell containing metal oxides using any suitable method, such as vapor deposition, atomic layer deposition (ALD), sputtering, or evaporation (these are techniques well known in the art).

[0099] The shell material may be a weakly alkaline material. However, the alkalinity of the shell material is insufficient to produce the desired pH change, especially according to the previously described buffer test or disk buffer test (as described later).

[0100] In some embodiments, the shell, or in other words, the sealant, has an average thickness of at least 5 nm, 10 nm, 15 nm, 20 nm, or 25 nm. The shell thickness can range up to 250 nm, 500 nm, 750 nm, or 1000 nm (1 micrometer). In some embodiments, such as in the case of encapsulated dental fillers, the shell thickness typically ranges up to 50 nm, 75 nm, 100 nm, 150 nm, or 200 nm.

[0101] Based on weight percent, the shell material is typically at least 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, or 0.5 wt% of the total encapsulated material. Based on weight percent, the amount of shell material can range from up to 15 wt% or 20 wt% of the total encapsulated material, but more typically not greater than 10 wt%, 9 wt%, 8 wt%, 7 wt%, 6 wt%, or 5 wt%. In some embodiments, based on weight percent, the amount of shell material is not greater than 4.5 wt%, 4 wt%, 3.5 wt%, 3 wt%, 2 wt%, or 1 wt%.

[0102] In a preferred embodiment, the shell material and shell thickness are selected to allow controlled and / or delayed release or reaction of the alkaline core material.

[0103] In a preferred embodiment, the shell is initially impermeable (i.e., the materials from the composition and the core material cannot interact through the shell via simple diffusion). Interactions occur after the shell is altered by interaction with other materials (e.g., degrading, corroding, or dissolving). Compositions (e.g., two-part compositions) containing components that degrade the shell, such as water or acid, can be designed. In other embodiments, shell degradation can occur due to contact with water or acidic components during use. In this embodiment, the source or water or acidic component can be a biological fluid (e.g., saliva or water retained in soft tissue surrounding teeth or bone).

[0104] In some embodiments, the concentration of the (e.g., encapsulated) alkaline material is typically at least 2%, 3%, 4%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, or 65% of the second portion of the curable dental sealant composition, ranging up to 100% by weight. The total curable (e.g., dental composition) contains half of this concentration of (e.g., encapsulated) alkaline material. Therefore, the concentration of the (e.g., encapsulated) alkaline material is typically at least 1%, 1.5%, 2%, 2.5%, 5%, 7.5%, 10%, 12.5%, 15%, 17.5%, 20%, 22.5%, 25%, 27.5%, 30%, or 32.5% by weight of the total curable dental sealant composition, ranging up to 50% by weight. The concentration can be selected based on the strength of the alkaline (e.g., encapsulated) material and the desired properties of the dental sealant composition.

[0105] Referring to Tables 4 through 7 of previously cited 78772WO003, in one embodiment, the unencapsulated (e.g., Portland adhesive or tricalcium silicate) alkaline material provides an alkaline pH (e.g., at least 8.5, 9, 9.5, 10, or 10.5) for 1 minute when subjected to the aforementioned buffer test. However, according to the buffer test, the encapsulated (e.g., Portland adhesive or tricalcium silicate) alkaline material does not provide an alkaline pH (e.g., at least 8.5, 9, 9.5, 10, or 10.5) for 2 minutes, 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, or 10 minutes or longer. In some embodiments, the encapsulated (e.g., Portland adhesive) alkaline material does not provide an alkaline pH (e.g., at least 8.5, 9, 9.5, 10, or 10.5) for 15 minutes, 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, or 45 minutes. In some implementations, the encapsulated (e.g., Portland adhesive) alkaline material does not provide an alkaline pH (e.g., at least 8.5, 9, 9.5, 10, or 10.5) for 100, 200, or 300 minutes.

[0106] In another embodiment, the unencapsulated (e.g., bioactive glass) alkaline material, when subjected to the aforementioned buffer test, provides an alkaline pH (e.g., at least 8.5, 9, 9.5, 10, or 10.5) within 5 minutes. However, according to the buffer test, the encapsulated (e.g., bioactive glass) alkaline material does not provide an alkaline pH (e.g., at least 8.5, 9, 9.5, 10, or 10.5) for 30-40 minutes.

[0107] In another embodiment, an unencapsulated (e.g., Portland adhesive) alkaline material provides an alkaline pH of 11.5 within 20 seconds when tested in deionized water. However, an encapsulated (e.g., Portland adhesive) alkaline material provides an alkaline pH of at least 8.5 within 20 seconds when tested in deionized water. In another embodiment, an unencapsulated (e.g., bioactive glass) alkaline material provides an alkaline pH of 10.5 within 20 seconds when tested in deionized water. However, an encapsulated (e.g., bioactive glass) alkaline material provides an alkaline pH of at least 9.8 within 20 seconds when tested in deionized water. Therefore, pH changes in acidic (e.g., buffer solutions) solutions can occur at a significantly slower rate than in deionized water.

[0108] In a preferred embodiment, the delayed release or reaction of the alkaline (e.g., core) material serves to increase the alkalinity of the hardened dental sealant material and neutralize acids that later form in the oral environment near the cured sealant. Unencapsulated strongly alkaline materials can produce a desired large (but not desirablely rapid) increase in pH. The same encapsulated alkaline material can produce a desired pH increase, but after a longer duration, or provide a slow, continuous release of the alkaline material (e.g., hydroxyl ions).

[0109] The alkalinity of a carrier material (such as a hardened dental sealant composition containing encapsulated or unencapsulated alkaline material) can be estimated by measuring the pH change of a disk (3.1 mm × 1.3 mm high) of hardened (i.e., cured) material immersed in 1.5 ml of 10 mM Na₂HPO₄ (commonly referred to as PBS) buffer solution contained in a 2 ml plastic centrifuge tube. The PBS buffer solution can be prepared by dissolving 8 g NaCl, 0.2 g KCl, 1.44 g Na₂HPO₄, and 0.24 g KH₂PO₄ in 800 ml distilled H₂O, adjusting the pH to 7.4 with HCl, bringing the volume to 1 L with additional distilled water, and then autoclaving. This test will subsequently be referred to as the disk buffer test.

[0110] Representative two-part hardenable dental sealant compositions that can be used for disc cushioning tests are further described in the examples below.

[0111] In some embodiments, the hardened dental sealant composition containing encapsulated or unencapsulated alkaline material increases the pH of the buffer solution by at least 0.05, 0.10, 0.15, 0.20, 0.25, or 0.30 over 15 or 39 hours.

[0112] The hardened dental sealant composition is initially neutral in water (pH 7 to 7.5), and its alkalinity increases over various time periods ranging from 1 hour to 1 day (pH at least 8, 8.5, 9, 9.5, 10, 10.5, or 11), and in some embodiments, the alkalinity increases over up to 2, 3, 4, 5, 6, or 7 days or more. However, the hardened dental sealant composition can remain neutral (pH 7 to 7.5) because the neutralization reaction proceeds at a rate equal to the release rate of the alkaline (e.g., core) material, as the released alkali neutralizes the acid present in the oral environment.

[0113] In some embodiments, for compositions containing more than 16.25% by weight of encapsulated alkaline material, the encapsulated or unencapsulated alkaline material provides an alkaline pH (e.g., at least 8.5, 9, 9.5, 10, or 10.5) for 46 hours, 72 hours, 100 hours, 147 hours, 260 hours, 360 hours, or 500 hours.

[0114] Dental sealant compositions may optionally include additional additives suitable for the oral environment, including flavoring agents, antimicrobial agents, fragrances, stabilizers, viscosity modifiers, rheology modifiers, inhibitors, and ultraviolet (UV) absorbers (for embodiments in which the dental sealant does not cure by exposure to UV light). Other suitable additives include agents that impart fluorescence and / or milky white light.

[0115] In some embodiments, the cured dental sealant has a tooth-like white appearance. In this embodiment, at least one portion of the dental sealant typically also contains a light-shielding filler. Suitable fillers include, for example, titanium dioxide, zirconium oxide, alumina, or silica. The average particle size of the light-shielding filler is typically at least 0.1 micrometers or 0.2 micrometers, and ranges up to 0.7 micrometers or 1 micrometer. In some embodiments, as described below, the encapsulating material comprising an alkaline core material and an inorganic shell material is the sole or primary light-shielding filler.

[0116] The concentration of the light-shielding filler is typically at least 0.05 wt%, 0.10 wt%, 0.15 wt%, 0.2 wt%, and up to 5 wt%.

[0117] The optimal amount of light-shielding filler will vary depending on the particle size distribution and refractive index of the filler and the cured resin system. The greater the refractive index difference between the filler and the cured resin, the higher the efficiency of the filler in shielding.

[0118] In typical implementations, suspending agents, such as pyrolytic silica, can be used. Pyrolytic silica is available under the trade name "Cab-O-Sil" from Cabot Corporation and under the trade name "Aerosil" from Degussa, Inc. Suspension agents thicken the composition, thereby increasing its viscosity.

[0119] The concentration of the suspending agent is typically at least 0.05 wt%, 0.10 wt%, 0.15 wt%, 0.2 wt%, and up to 5 wt%. When using a higher concentration of alkaline material, the concentration of the suspending agent can be reduced to maintain a sufficiently low viscosity.

[0120] In a typical implementation, the light-shielding filler and suspending agent comprise a hydrophobic (e.g., organosilane) surface treatment agent. The process described in U.S. Patent No. 3,066,112, which is incorporated herein by reference, can be used to treat the filler. A useful reactive organosilane for this purpose is γ-methacryloyloxypropyltrimethoxysilane (“A-174”, commercially available from Union Carbide).

[0121] The dental sealant compositions described herein are typically prepared by first mixing a polymerizable resin with an oxidizing or reducing agent and other optional additives. Then, a light-shielding filler and a suspending agent are mixed under high shear conditions until a homogeneous dispersion is obtained.

[0122] The present invention is illustrated by the following examples.

[0123] Material

[0124] Camphorquinone (CPQ), benzoyl peroxide-LUPEROX A75 (BPO), 2-(4-dimethylamino)phenyl)ethanol (DMAPE), triethylene glycol dimethacrylate (TEGDMA), and bisphenol A glyceride dimethacrylate (BisGMA) were all obtained from Sigma-Aldrich.

[0125] 2,6-Di-tert-butyl-4-methylphenol (BHT) was obtained from PMC Specialties Incorporated, Cincinnati, OH.

[0126] The pyrolytic silica (AEROSIL R972) was obtained from Evonik Corporation (Piscataway, NJ).

[0127] Portland Adhesive: White Portland Adhesive (Federal White Type 1, ASTM C150) was purchased from Woodstock, Ontario, Canada. The major components of the composition, as reported by the manufacturer, are tricalcium silicate (3CaO-SiO2), dicalcium silicate (2CaO-SiO2), tricalcium aluminate (3CaO-Al2O3), tetracalcium aluminoferrite (4CaO-Al2O3-Fe2O3), magnesium oxide, calcium oxide, potassium sulfate, and sodium sulfate. Portland adhesive is a strongly alkaline material containing multiple components. Each major component (excluding trace amounts of magnesium oxide, potassium sulfate, and sodium sulfate) contains a significant amount of the strong base (CaO). Portland adhesive typically contains approximately 61%–69% CaO, approximately 18%–24% SiO2, approximately 2%–6% Al2O3, approximately 1%–6% Fe2O3, and approximately 0.5%–5% MgO.

[0128] calculate

[0129] The following formulas 1 to 6 are used to calculate the shell thickness, core material weight % and shell material weight % of the encapsulated material prepared by the methods described in Examples 1 to 2. In the calculations, the total surface area of ​​the core material is determined by representing the particles of the core material powder as spheres (surface area = 4π(d / 2)). 2 Volume = (4 / 3)(π)(d / 2) 3 ).

[0130] Formula 1 :

[0131] ST em (cm) = the thickness of the encapsulated material.

[0132] V mo (cm) 3 = Volume of metal oxides prepared by APCVD method.

[0133] SA c (cm) 2 = Total surface area of ​​the core material powder.

[0134] Formula 2 :

[0135] FR cg (cm) 3 / min) = Carrier gas flow rate (for Al2Me6, TiCl4, SiCl4).

[0136] CT (min) = coating time.

[0137] CA = cation per mole of precursor material.

[0138] MW mo (g / mol) = Molecular weight of a cationic metal oxide per mole (for Al2O3MW) mo =51 g / mol, for TiO2MW mo =80 g / mol, for SiO2 MW mo =60g / mol).

[0139] D mo (g / cm) 3 = Density of metal oxides (for Al2O3 D) mo =3.0, for TiO2 D mo =3.0, for SiO2D mo =2.2).

[0140] %P = the molar percentage of the metal oxide precursor contained in the carrier gas (%P = 1.33% for Al2Me6, %P = 1.33% for TiCl4, and %P = 35.7% for SiCl4).

[0141] EDE = Estimated deposition efficiency of APCVD used in the examples (EDE = 0.5 for Al2O3, EDE = 0.6 for TiO2, EDE = 0.4 for SiO2).

[0142] Formula 3 :

[0143] N cp = The number of powder particles in the core material.

[0144] Formula 4 :

[0145] Mcp(g) = the amount of core powder material (bioactive glass, Portland binder, tricalcium silicate) used in the APCVD method.

[0146] Msm(g) = the amount of metal oxides (Al2O3, TiO2, SiO2) deposited by APCVD.

[0147] Msm(g) = V mo D mo

[0148] D cp(g / cm) 3 = Density of the core powder material (Dcp = 2.65 for bioactive glass, Dcp = 3.11 for Portland adhesive).

[0149] d (cm) = diameter of the core particle.

[0150] Formulas 5 and 6 - Weight percentage of the encapsulating material (weight %): Casing weight percentage = 100

[0151] Core weight percentage = (100 - shell weight percentage).

[0152] Measurement

[0153] Viscosity measurements were determined using a Brookfield DV-I+ viscometer (AMETEK Brookfield, Middleboro, MA) with a HELIPATH support and an A-type T-shaped rotor. Measurements were taken at 23°C and 100 s. -1 The test is performed at a shear rate of [missing information]. Results are obtained once the viscosity measurement has stabilized (typically within 0.5 to 2 minutes). Viscosity is reported in centipoises (cP).

[0154] Example 1. Encapsulation material 1 (PC core and AO shell)

[0155] Portland binder (PC) was encapsulated with an alumina (AO)-based material using atmospheric pressure chemical vapor deposition (APCVD). The Portland binder powder was coated by reacting trimethylaluminum (obtained from Strem Chemicals, Newburyport, MA, and dispensed using a stainless steel bubbler) with water vapor in a fluidized bed reactor. The reactor was a glass frit funnel tube (12 cm diameter, 30 cm height). The reactor had an inlet pipe extending below the glass frit path parallel to the reactor body and an extended top region above the glass frit to allow for desired reactor height and fittings for the precursor injector pipe and vent. The temperature was controlled at 180°C using an oil bath. A nitrogen carrier gas with a standard bubbler configuration for liquid precursors was used. The bubbler was maintained at an ambient temperature of approximately 22°C. The flow rate through the trimethylaluminum (TMA) bubbler was 1773 cm⁻¹. 3 / minute. The flow velocity through the water bubbler is 5307 cm⁻¹. 3 / minute. The total coating time is 120 minutes. The amount of Portland adhesive added to the reactor is 800g, and the particle size of the Portland adhesive powder is 20 microns.

[0156] Before being added to the reactor, fine and coarse particles were removed from the Portland binder sample using an AVEKA CCE Model 100 centrifugal air classifier (AVEKA CCE LLC, Cottage Grove, MN). In the first step, approximately 24% of the coarse tailings from the initial sample were removed, and then in the second step, approximately 25% of the fine tailings were removed from the remaining sample. The resulting Portland binder powder had an average particle size of 20 micrometers, as determined using a Coulter Multisizer 3 counter (Beckman Coulter Company, Brea, CA).

[0157] The encapsulated material 1 is calculated to have a shell thickness of 46 nm. The calculated weight percentage (wt%) is 98.8 wt% core material and 1.2 wt% shell material.

[0158] Example 2. Encapsulation material 2 (PC core and AO shell)

[0159] Portland binder (PC) was encapsulated with an alumina (AO)-based material using atmospheric pressure chemical vapor deposition (APCVD). The Portland binder powder was coated by reacting trimethylaluminum (obtained from Strem Chemicals and dispensed using a stainless steel bubbler) with water vapor in a fluidized bed reactor. The reactor was a glass frit funnel tube (12 cm diameter, 30 cm height). The reactor had an inlet pipe extending below the glass frit path parallel to the reactor body and an extended top region above the glass frit to allow for desired reactor height and fittings for the precursor injector pipe and vent. The temperature was controlled at 180°C using an oil bath. A nitrogen carrier gas with a standard bubbler configuration for liquid precursors was used. The bubbler was maintained at an ambient temperature of approximately 22°C. The flow rate through the trimethylaluminum (TMA) bubbler was 2670 cm⁻¹. 3 / minute. The flow velocity through the water bubbler is 8032 cm⁻¹. 3 / minute. The total coating time is 190 minutes. The amount of Portland adhesive added to the reactor is 1500g, and the particle size of the Portland adhesive powder is 20 microns.

[0160] Before being added to the reactor, fine and coarse particles were removed from the Portland binder sample using an AVEKA CCE Model 100 centrifugal air classifier (AVEKA CCE). In the first step, approximately 24% of the coarse tailings from the initial sample were removed, and then in the second step, approximately 25% of the fine tailings were removed from the remaining sample. The resulting Portland binder powder had an average particle size of 20 micrometers, as determined using a Coulter Multisizer 3 counter (Beckman Coulter).

[0161] The encapsulated material 2 is calculated to have a shell thickness of 58 nm. The calculated weight percentage (wt%) is 98.5 wt% core material and 1.5 wt% shell material.

[0162] Example 3.

[0163] The composition of paste AA-1 is reported in Table 1 (each component is reported as % by weight). Paste AA-1 was prepared in batches. BisGMA and TEGDMA were combined (1:1 by weight) and stirred until homogeneous. The BisGMA / TEGDMA mixture was combined with BPO and CPQ in a mixing cup. The filled cup was placed in a FlackTek SPEEDMIXER (FlackTek Incorporated, Landrum, SC, South Carolina) and the contents were mixed at 2400 rpm until a homogeneous mixture was obtained. Pyrolytic silica (AEROSIL R972) was added to the cup. The cup was placed in a FlackTek SPEEDMIXER and the contents were mixed at 2400 rpm until a homogeneous mixture of paste AA-1 was obtained. The viscosity of paste AA-1 was 1130 ± 9 cP (at 23°C and 100 s). -1 (at the shear rate).

[0164] The composition of paste BB-1 is reported in Table 2 (each component is reported as % by weight). Combine BisGMA and TEGDMA (1:1 by weight) and stir until homogeneous. In a mixing cup, combine the BisGMA / TEGDMA mixture with DMAPE and BHT. Place the filled cup in a FlackTek SPEEDMIXER and mix the contents at 2400 rpm until a homogeneous mixture is obtained. Add pyrolytic silica (AEROSIL R972) to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at 2400 rpm until a homogeneous mixture is obtained. Add encapsulated material 1 to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at 2400 rpm until a homogeneous mixture of paste BB-1 is obtained. The viscosity of paste BB-1 is 1450 ± 12 cP (at 23°C and 100 s). -1 (at the shear rate).

[0165] Table 1: Composition of Paste AA-1

[0166] Table 2: Composition of Paste BB-1

[0167] Example 4.

[0168] The composition of paste BB-2 is reported in Table 3 (each component is reported as a percentage by weight). Combine BisGMA and TEGDMA (1:1 by weight) and stir until homogeneous. In a mixing cup, combine the BisGMA / TEGDMA mixture with DMAPE and BHT. Place the filled cup in a FlackTek SPEEDMIXER and mix the contents at 2400 rpm until a homogeneous mixture is obtained. Add pyrolytic silica (AEROSIL R972) to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at 2400 rpm until a homogeneous mixture is obtained. Add encapsulated material 2 to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at 2400 rpm until a homogeneous mixture of paste BB-1 is obtained.

[0169] Pastes AA-1 and BB-2 were equilibrated in a room at 37°C and then combined on a mixing pad at a volume ratio of approximately 1:1. The resulting sealant composition hardened after two minutes.

[0170] When pastes AA-1 and BB-2 were combined in a 1:1 volume ratio on a mixing pad at room temperature (approximately 23°C) without the use of a curing lamp (dark curing), the sample did not harden after two minutes.

[0171] Alternatively, pastes AA-1 and BB-2 are combined on a mixing pad at a 1:1 volume ratio at room temperature (approximately 23°C) and immediately applied using Elipar. ™ The sealant composition was cured using a DeepCure-S LED curing lamp (3M Oral Care, Maplewood, MN). The sealant composition hardened 10 seconds after exposure to light.

[0172] Table 3: Composition of Paste BB-2

[0173] Example 5.

[0174] The composition of paste AA-2 is reported in Table 4 (each component is reported as % by weight). Paste AA-2 was prepared in batches. BisGMA and TEGDMA were combined (1:1 by weight) and stirred until homogeneous. In a mixing cup, the BisGMA / TEGDMA mixture was combined with BPO and CPQ. The filled cup was placed in a FlackTek SPEEDMIXER, and the contents were mixed at 2400 rpm until a homogeneous mixture was obtained. Pyrolytic silica (AEROSIL R972) was added to the cup. The cup was placed in a FlackTek SPEEDMIXER, and the contents were mixed at 2400 rpm until a homogeneous mixture of paste AA-2 was obtained.

[0175] The composition of paste BB-3 is reported in Table 5 (each component is reported as a percentage by weight). Combine BisGMA and TEGDMA (1:1 by weight) and stir until homogeneous. In a mixing cup, combine the BisGMA / TEGDMA mixture with DMAPE and BHT. Place the filled cup in a FlackTek SPEEDMIXER and mix the contents at 2400 rpm until a homogeneous mixture is obtained. Add pyrolytic silica (AEROSIL R972) to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at 2400 rpm until a homogeneous mixture is obtained. Add encapsulated material 2 to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at 2400 rpm until a homogeneous mixture of paste BB-2 is obtained.

[0176] Without using a curing lamp (dark curing), pastes AA-2 and BB-3 were combined on a mixing pad at a 1:1 volume ratio at room temperature (approximately 23°C). The resulting sealant composition cured within 1 minute.

[0177] Alternatively, pastes AA-2 and BB-3 are combined in a 1:1 volume ratio on a mixing pad at room temperature (approximately 23°C) and immediately applied using Elipar. ™ The sealant composition was cured using a DeepCure-S LED curing lamp (3M Oral Care). The resulting sealant composition hardened 10 seconds after exposure to light.

[0178] Table 4: Composition of Paste AA-2

[0179] Table 5: Composition of paste BB-3

[0180] Example 6.

[0181] Use such as Figures 1 to 4 The aforementioned dual-chamber syringe device has a dispensing nozzle and a static mixer. The dimensions of the syringe device are as follows: cartridge length = 73.8 mm, cartridge outer diameter = 8.4 mm, volume of each chamber = 1 mL, total volume of the dispensing nozzle = 0.03 mL, diameter of the dispensing nozzle outlet orifice = 0.85 mm, nozzle head length = 9 mm, and nozzle head internal angle = 120°. [The remaining text appears to be a fragment and requires further context for accurate translation.] Figure 4 The static mixer is inserted into the tube portion of the dispensing nozzle. The total length of the series of mixing blades is 15 mm. Each of the two chambers has a substantially D-shaped cross-section, and the D-shapes are oriented in a mirror manner relative to each other.

[0182] One chamber of the syringe was partially filled with paste AA-2 (2 / 3 volume). The second chamber was partially filled with paste BB-3 (2 / 3 volume). After depressing the plunger, the filled syringe metered a 1:1 volume ratio of paste AA-2 and paste BB-3 into the dispensing nozzle. An orthodontic model of the upper dental arch in the patient's mouth, with each tooth having a deep cleft, was used. A thin coating of the sealant composition was applied to the surface of 10 teeth in the model using the syringe apparatus. It was observed that the sealant composition penetrated into the clefts after application. The total time for applying the sealant composition to the ten teeth was approximately 45 seconds. The sealant composition hardened approximately 45 seconds after application to the teeth.

[0183] Example 7.

[0184] Using the dual-chamber syringe apparatus as described in Example 6, one chamber of the syringe was partially filled with paste AA-1 (2 / 3 volume). The second chamber was partially filled with paste BB-1 (2 / 3 volume). After depressing the plunger, the filled syringe metered a 1:1 volume ratio of paste AA-1 and paste BB-1 into the dispensing nozzle. Using the syringe apparatus, the Teflon disc mold (3.1 mm diameter and 1.3 mm height) was filled with the paste. The paste was then cured for 20 seconds on each side of the mold using an ELIPAR S10 curing lamp (3M Oral Care). The resulting molded disc was immediately removed from the mold and placed in a 2 mL plastic centrifuge tube containing 0.5 mL of buffer solution, 15 g of deionized water, and 10 g of pH 4 buffer solution (buffer solution BDH5018, VWR International). The disc was completely submerged in the buffer solution. The tube was capped and stored at room temperature.

[0185] The pH of the buffer solution was measured using an ORION PERPHECT ROSS pH microelectrode (catalog number 8220BNWP, Thermo Fisher Scientific Company, Waltham, PA). The sample was gently shaken before each measurement. pH measurements were taken immediately after immersion of the pan in the buffer solution (0 hours in the table), and at 15 and 39 hours after immersion.

[0186] The molded discs for the comparative examples were prepared and tested according to the procedures described, with the only change being that paste BB-1 was replaced with paste BB-C1 of material 1 without any encapsulation (Table 6). pH characteristics are reported in Table 7.

[0187] Table 6: Composition of paste BB-C1

[0188] Example 8.

[0189] The same procedures and testing methods as described in Example 7 were followed, except that the encapsulating material 1 in paste BB-1 was replaced with an equal amount of unencapsulated Portland adhesive (wt% = 10%). The only change to the procedure was that paste BB-1 contained no encapsulating material 2. pH characteristics are reported in Table 6.

[0190] Table 7: pH measurements of PBS solutions in contact with the molded discs prepared according to Examples 7 and 8

[0191] Example 9.

[0192] The composition of paste BB-4 is reported in Table 8 (each component is reported as a percentage by weight). BisGMA and TEGDMA can be combined (1:1 by weight) while stirring until homogeneous. In a mixing cup, combine the BisGMA / TEGDMA mixture with DMAPE and BHT. Place the filled cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture is obtained. Add pyrolytic silica (AEROSIL R972) to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture is obtained. Add encapsulated material 1 to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture of paste BB-4 is obtained.

[0193] Paste AA-1 and BB-4 are combined on a mixing pad in a volume ratio of about 1:1 to provide the resulting sealant composition.

[0194] Example 10.

[0195] The composition of paste BB-5 is reported in Table 8 (each component is reported as a percentage by weight). BisGMA and TEGDMA can be combined (1:1 by weight) while stirring until homogeneous. In a mixing cup, combine the BisGMA / TEGDMA mixture with DMAPE and BHT. Place the filled cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture is obtained. Add pyrolytic silica (AEROSIL R972) to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture is obtained. Add encapsulated material 1 to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture of paste BB-5 is obtained.

[0196] Paste AA-1 and BB-5 are combined on a mixing pad in a volume ratio of about 1:1 to provide the resulting sealant composition.

[0197] Example 11.

[0198] The composition of paste BB-6 is reported in Table 8 (each component is reported as a percentage by weight). BisGMA and TEGDMA can be combined (1:1 by weight) while stirring until homogeneous. In a mixing cup, combine the BisGMA / TEGDMA mixture with DMAPE and BHT. Place the filled cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture is obtained. Add pyrolytic silica (AEROSIL R972) to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture is obtained. Add encapsulated material 1 to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture of paste BB-6 is obtained.

[0199] Paste AA-1 and BB-6 are combined on a mixing pad in a volume ratio of about 1:1 to provide the resulting sealant composition.

[0200] Example 12.

[0201] The composition of paste BB-7 is reported in Table 8 (each component is reported as a percentage by weight). BisGMA and TEGDMA can be combined (1:1 by weight) while stirring until homogeneous. In a mixing cup, combine the BisGMA / TEGDMA mixture with DMAPE and BHT. Place the filled cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture is obtained. Add pyrolytic silica (AEROSIL R972) to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture is obtained. Add encapsulated material 1 to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture of paste BB-7 is obtained.

[0202] Paste AA-1 and BB-7 are combined on a mixing pad in a volume ratio of approximately 1:1 to provide the resulting sealant composition.

[0203] Example 13.

[0204] The composition of paste BB-8 is reported in Table 8 (each component is reported as a percentage by weight). BisGMA and TEGDMA can be combined (1:1 by weight) while stirring until homogeneous. In a mixing cup, combine the BisGMA / TEGDMA mixture with DMAPE and BHT. Place the filled cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture is obtained. Add pyrolytic silica (AEROSIL R972) to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture is obtained. Add encapsulated material 1 to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture of paste BB-8 is obtained.

[0205] Paste AA-1 and BB-8 are combined on a mixing pad in a volume ratio of about 1:1 to provide the resulting sealant composition.

[0206] Example 14.

[0207] The composition of paste BB-9 is reported in Table 8 (each component is reported as a percentage by weight). BisGMA and TEGDMA can be combined (1:1 by weight) while stirring until homogeneous. In a mixing cup, combine the BisGMA / TEGDMA mixture with DMAPE and BHT. Place the filled cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture is obtained. Add pyrolytic silica (AEROSIL R972) to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture is obtained. Add encapsulated material 1 to the cup. Place the cup in a FlackTek SPEEDMIXER and mix the contents at approximately 2400 rpm until a homogeneous mixture of paste BB-9 is obtained.

[0208] Paste AA-1 and BB-9 are combined on a mixing pad in a volume ratio of about 1:1 to provide the resulting sealant composition.

[0209] Table 8: Composition of pastes BB-4, BB-5, BB-6, BB-7, BB-8 and BB-9

Claims

1. A two-part dental sealant composition, said composition comprising: The first part comprises (meth)acrylate resin and an oxidizing curing agent, wherein, based on the total weight of all components of the dental material, the dental sealant composition contains 0.01% to 10% by weight of the oxidizing curing agent. The first part is characterized by a viscosity of no more than 5000 cps; The second part comprises (meth)acrylate resin and a reduction curing agent. The second part is characterized by a viscosity not exceeding 5000 cps; and The encapsulating material comprises: Core, the core comprising: Alkaline materials or alkaline compounds, characterized in that pKa is 8 to 14, and A calcium ion source derived from the alkaline material or the alkaline compound, a calcium compound different from the alkaline material or the alkaline compound, or a combination thereof; as well as The housing contains a metal oxide. The housing surrounds the core, and The shell described herein will degrade, dissolve, or decompose when in contact with water or acidic components.

2. The two-part dental sealant composition according to claim 1, wherein the (meth)acrylate resin of the first part and the (meth)acrylate resin of the second part each comprise bisphenol A glycidyl methacrylate and triethylene glycol dimethacrylate.

3. The two-part dental sealant composition according to claim 1, wherein the oxidizing curing agent is a peroxide.

4. The two-part dental sealant composition according to claim 1, wherein the reducing curing agent is an amine.

5. The two-part dental sealant composition according to claim 1, wherein the core further comprises a phosphorus ion source, a fluoride ion source, or a combination thereof.

6. The two-part dental sealant composition according to claim 1, wherein the core comprises tricalcium silicate, dicalcium silicate, calcium silicate, tricalcium aluminate, tetracalcium aluminoferrite, or a combination thereof.

7. The two-part dental sealant composition according to claim 6, wherein the core further comprises magnesium oxide, calcium oxide, potassium sulfate, sodium sulfate, or a combination thereof.

8. The two-part dental sealant composition of claim 1, wherein the core comprises bioactive glass or Portland adhesive.

9. The two-part dental sealant composition of claim 1, wherein the composition further comprises a filler comprising zirconium oxide, silica, or a combination thereof.

10. The two-part dental sealant composition of claim 1, wherein the alkaline material or the alkaline compound is present in an amount of at least 25% by weight based on the weight of the core.

11. The two-part dental sealant composition according to claim 1, wherein the metal oxide is characterized by a pKa of at least 6 and less than 8.

12. The two-part dental sealant composition of claim 1, wherein the thickness of the shell is at most 500 nm.

13. The two-part dental sealant composition of claim 1, wherein the second part comprises the encapsulating material.

14. The two-part dental sealant composition of claim 1, wherein the composition further comprises a photoinitiator.

15. Use of the two-part dental sealant composition according to any one of claims 1 to 14 in the preparation of a medicament for sealing teeth.

16. A kit, the kit comprising: Syringe device, the syringe device comprising: The cartridge includes a first chamber and a second chamber. A plunger, comprising a first rod and a second rod, Wherein the first rod seals the first chamber and the second rod seals the second chamber, and At least one removable dispensing nozzle, said at least one removable dispensing nozzle comprising a static mixer and an outlet, The at least one removable dispensing nozzle is attached to the end of the cartridge opposite the plunger; and The two-part dental sealant composition according to any one of claims 1 to 14, The first part is located in the first chamber, and The second part is located in the second chamber.

17. The kit of claim 16, wherein the volume of the cartridge is not greater than 5 cc.

18. The kit of claim 16, wherein the volume ratio of the first chamber to the second chamber is approximately 1:

1.

19. The kit of claim 16, wherein the volume of the at least one removable dispensing nozzle is not greater than 0.25 cc.

20. The kit of claim 16, wherein the diameter of the outlet is not greater than 1.5 mm.

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