Nanostructures, Nanocomposites, and Their Implementations

Abstract

The present disclosure relates to nanostructures comprising 50 to 80% (w / w) magnetic material and 20 to 50% (w / w) calcium silicate. The present disclosure further relates to nanocomposites comprising the nanostructures disclosed herein together with an additive. The present disclosure also provides gels comprising the nanostructures or nanocomposites and an additive, and methods thereof.

Description

Technical Field

[0001] The subject matter disclosed herein relates generally to the field of oral healthcare and, more particularly, to magnetic nanostructures and nanocomposites for use in the treatment of tooth hypersensitivity.

Background Art

[0002] Dentin hypersensitivity (DH) as a chronic disease is becoming increasingly prevalent among adults and consists of sharp pain arising from dentin exposed in response to various combinations of stimuli, such as dietary factors like ice-cold beverages and environmental conditions such as exposure to colder winter atmospheres. The heterogeneity of problems associated with DH ranges from minor discomfort to intolerable pain and up to disruption of a quality of life approaching incapacity. It can affect patients of all age groups, most commonly the canines and premolars of both dental arches. The intensity and degree of sensitivity depend on different factors and vary from person to person.

[0003] The main causative factors of DH include hard tissue loss that can result in abrasion, attrition, erosion, and tooth grinding, as well as gingival recession that may be caused by periodontal disease, poor brushing, and periodontal interventions. Microscopic investigations have revealed that these factors enhance DH at the location of dentin exposed due to the removal or degradation of the enamel coating layer. The hydrodynamic theory proposed by Brannstorm is based on the movement of fluid inside the dentinal tubules that are open between the dentin surfaces and exposed to the environment and the pulp. As a result of any stimulus in the immediate vicinity of the exposed dentin surface, the movement of fluid in the dentinal tubules is affected either towards or away from the pulp. The said change in the movement of dentinal fluid switches the signal of the nerve tissue of the pulp, resulting in a sensation of pain.

[0004] In new research on the determination of etiological factors in the causal relationship of diseases, many materials and methods for reducing or eliminating sensitivity have been discovered for its diagnosis and treatment. Such materials usually exert their effects by "sealing dentinal tubules" or "interfering with the transmission of nerve impulses". Some of these materials include the use of potassium salt-containing toothpaste, fluoride composites, resins, lasers, bioglass, etc. For example, Patent Document 1 relates to a toothpaste composition for DH that effectively prevents pain caused by DH and instantaneously and sufficiently seals the openings of dentinal tubules on the exposed dentin surface. The toothpaste composition includes a powder having a hardly water-soluble property, a desensitizer, and water.

[0005] Patent Document 2 relates to a DH inhibitor in which a liquid or aqueous paste is mainly composed of tetracalcium phosphate particles (A), alkali metal phosphate salts (B), acidic calcium phosphate particles (C), and water. The inhibitor composition is used to seal dentinal tubules by rubbing them onto the dentin surface.

[0006] Despite ongoing research and established methods, the problem of DH is clearly increasing in different age groups. Furthermore, the fact that conventional medicines and methods cannot seal the openings of dentinal tubules for a longer period has consistently caused problems. For the reasons mentioned above, interfering with the transmission of nerve impulses from the exposed dentin surface to the nerve tissue (pulp) seems to be a more suitable and better solution for preventing or eradicating DH. Therefore, there is still an urgent and up-to-date need to develop methods or medicines based on interrupting the transmission of nerve impulses, thereby facilitating a more permanent and long-lasting prevention of pain caused by DH.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

SUMMARY OF THE INVENTION

MEANS FOR SOLVING THE PROBLEM

[0008] In a first aspect of the present disclosure, the nanostructure contains 50 to 80% (w / w) of a magnetic material and 20 to 50% (w / w) of calcium silicate, magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, and the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 of surface area; and pore diameters in the range of 2 nm to 20 nm.

[0009] In a second aspect of the present disclosure, a nanocomposite comprising: a) 95 to 99.9% (w / w) of a nanostructure containing (i) 50 to 80% (w / w) of a magnetic material and (ii) 20 to 50% (w / w) of calcium silicate; and b) 0.1 to 5% (w / w) of an additive selected from calcium oxide, phosphorus, sodium, strontium, phosphate, fluorine, or combinations thereof, wherein magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 of surface area; and pore diameters in the range of 2 nm to 20 nm, is provided.

[0010] In a third aspect of the present disclosure, a method for preparing a nanostructure, comprising: (a) mixing an oxidizing agent and a magnetic metal salt in a first solvent, and subsequently adding a base and a silicate precursor to obtain a first mixture; (b) contacting a calcium salt with the first mixture in the presence of a second solvent to obtain a second mixture; and (c) annealing the second mixture at a temperature in the range of 550 to 650 °C to obtain glassy calcium silicate as the shell of the nanostructure, followed by filtering and drying to obtain the nanostructure, wherein the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2A method is provided that has a surface area in the range of; and a pore diameter in the range of 2 nm to 20 nm.

[0011] In a fourth aspect of the present disclosure, a method for preparing a nanocomposite, comprising: a) preparing a nanostructure disclosed herein; and b) immersing the nanostructure in a solution containing a compound selected from calcium oxide, strontium salts, calcium fluoride, sodium fluoride, phosphates, or combinations thereof at a temperature in the range of 20 to 80 °C to obtain a nanocomposite. A method is provided.

[0012] In a fifth aspect of the present disclosure, a gel is provided that comprises: a) 0.1 to 10% (w / w) of a nanostructure or nanocomposite disclosed herein; b) 0.1 to 20% (w / w) of a hydrogel base; c) 0.1 to 1% (w / w) of a pH adjuster; d) 5 to 10% (w / w) of a wetting agent; e) 80 to 99% (w / w) of a swelling agent; f) 0.1% to 15% (w / w) of calcium oxide; and g) optionally 1 to 5% (w / w) of a stabilizer.

[0013] In a sixth aspect of the present disclosure, a method for preparing a gel, comprising: a) mixing a nanostructure or nanocomposite disclosed herein with a hydrogel base and a swelling agent to obtain a first solution; b) adding a pH adjuster and calcium oxide powder to the first solution to obtain a second solution; and c) adding a wetting agent and optionally a stabilizer to obtain a gel. A method is provided.

[0014] In a seventh aspect of the present disclosure, a method for treating tooth hypersensitivity is provided, comprising administering a nanostructure or nanocomposite or gel disclosed herein to a subject suffering from tooth hypersensitivity.

[0015] In an eighth aspect of the present disclosure, there is provided a method of administering a nanostructure or a nanocomposite or a gel disclosed herein, the method comprising applying, driving, and positioning the nanostructure or the nanocomposite or the gel disclosed herein to infected dentinal tubules using a magnetic cap.

[0016] In a ninth aspect of the present disclosure, there is provided a device comprising a nanostructure or a nanocomposite or a gel disclosed herein, and a magnetic cap.

[0017] In a tenth aspect of the present disclosure, there is provided the use of a nanostructure or a nanocomposite or a gel disclosed herein.

[0018] These and other features, aspects, and advantages of the present subject matter will be better understood with reference to the following description. This summary is provided to introduce a selection of concepts in a simplified form. This summary is not intended to identify key features or essential features of the claimed subject matter.

[0019] The following drawings form a part of this specification and are included to further illustrate aspects of the present disclosure. The present disclosure may be better understood by referring to the drawings in combination with the detailed description of specific embodiments presented herein.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

DETAILED DESCRIPTION OF THE INVENTION

[0021] Those skilled in the art are aware that the present disclosure is directed to variations and modifications other than those specifically described. It should be understood that the present disclosure includes all such variations and modifications. The present disclosure also includes such steps, features, compositions, and compounds, individually or collectively, as mentioned or shown herein, as well as all possible combinations of any or more of such steps or features.

[0022] Definitions For convenience, prior to further description of the present disclosure, specific terms used herein and in the examples are set forth herein. These definitions are to be read from the perspective of the remainder of the present disclosure and are to be understood as would be by those skilled in the art. The terms used herein have meanings recognized and known to those skilled in the art, but for convenience and completeness, specific terms and their meanings are set forth below.

[0023] The articles "a", "an", and "the" are used to refer to one or more (i.e., at least one) of the grammatical objects of the article.

[0024] The terms "comprise" and "comprising" are used in an inclusive and open-ended sense and mean that additional elements may be included. It is not intended to be construed as "consisting of only".

[0025] Throughout this specification, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", are to be interpreted as including an indicated element or step, or group of elements or steps but not excluding any other element or step, or group of elements or steps.

[0026] The term "including" is used to mean "including but not limited to". "Including" and "including but not limited to" are used interchangeably.

[0027] As used herein, the term "at least one" refers to one or more and thus includes individual components as well as mixtures / combinations.

[0028] The term "metal hydroxide" refers to a chemical substance containing metal cations and -OH anions and is often called the hydroxide of a metal. For the purposes of this disclosure, metal hydroxides include, but are not limited to, sodium hydroxide, potassium hydroxide, calcium hydroxide, and barium hydroxide.

[0029] The term "antibacterial agent" refers to any synthetic or natural compound that inhibits or prevents the growth and division of bacteria in the oral cavity. Various examples used as antibacterial agents for the purposes of this disclosure include, but are not limited to, hydrogen peroxide, ethanol, ciprofloxacin, norfloxacin, and gatifloxacin.

[0030] The term "magnetic cap" relates to a simple magnet or electromagnetic coil, or a magnetic device composed of other magnetic materials, for use in propelling nanostructures inside dentinal tubules. The magnetic cap may also be referred to as a magnetic clip and facilitates the movement of nanostructures (having a magnetic core) in a controlled manner under a magnetic field selected from the group of rotating magnetic fields, oscillating magnetic fields, inclined magnetic fields, elliptical magnetic fields, constant magnetic fields, or combinations thereof.

[0031] The term "zeta potential" refers to the electrokinetic potential at the interface in a colloidal system, which is used as a standard characterization technique for evaluating the surface of nanoparticles. In this context, the zeta potential was used to evaluate the surface charge of the nanostructure, i.e., its cationic, anionic, or neutral properties. The nanostructures disclosed herein have a zeta potential in the range of -20 to -40 mV.

[0032] The term "magnetic metal salt" refers to a metal salt that exhibits magnetic strength and ability in response to an applied magnetic field or a change in the applied magnetic field. For the purposes of this disclosure, salts selected from, but not limited to, iron chloride, iron nitrate, nickel chloride, nickel nitrate, cobalt chloride, cobalt nitrate, or combinations thereof can be used as magnetic metal salts.

[0033] The term "hydrogel-based" relates to the hydrated base in a gel composition that is convenient for use in oral therapy. For the purposes of this disclosure, the hydrogel-based material may be selected from, but not limited to, polyacrylic acid, diutan gum, alkyl acrylate cross-polymer, poloxamer, or combinations thereof. Alkyl acrylate cross-polymer refers to copolymers of various alkyl acrylates. Alkyl acrylate cross-polymer is obtained by polymerizing C 10~30 alkyl acrylate with various other acrylates including acrylic acid and methacrylic acid. Poloxamer is a non-ionic triblock copolymer that contains a hydrophobic chain of polyoxypropylene sandwiched between two hydrophilic chains of polyoxyethylene.

[0034] The term "pH adjuster" relates to a compound used to maintain the stability, shelf life, and pH of the nanostructure- or nanocomposite-based gel compositions disclosed herein. The pH adjuster may be selected from, but not limited to, triethanolamine, disodium tetraborate, TrisBase, or combinations thereof, in the context of this disclosure.

[0035] The term "humectant" relates to a hygroscopic substance used to maintain moisture in the gel compositions disclosed herein. It effectively aids in the long-term storage of the gel compositions. The humectant may be, but is not limited to, selected from glycerin, lecithin, propylene glycol, water, or combinations thereof for the purposes of this disclosure.

[0036] The term "swelling agent" relates to a substance used to create a mesoporous or breathable feel in the gel composition. For example, ethanol, water, or combinations thereof may be used as a swelling agent for the purpose of preparing the gel compositions disclosed herein.

[0037] The term "stabilizer" relates to a substance used to impart uniformity and stability to the gels disclosed herein. It imparts various properties to the gel composition that helps it to be easily pumpable or squeezable based on an improved consistency. In this disclosure, the stabilizer may be, but is not limited to, selected from xanthan gum, gelatin, starch, agar glyceride, or combinations thereof.

[0038] The term "additive" disclosed in this disclosure includes, but is not limited to, calcium oxide, phosphorus, sodium, strontium, phosphates, fluorine, or combinations thereof. The additive may be selected from sodium compounds, strontium compounds, phosphorus compounds, fluorine compounds, metal phosphates, or combinations thereof. The term "strontium salt" refers to any strontium compound that can be a source of strontium and is not limited to strontium halides, nitrates, and phosphates. The term "phosphate" includes, but is not limited to, metal phosphates.

[0039] The term "storage modulus" refers to the mechanical property of the gel disclosed herein that measures the stiffness of the gel. In other words, it corresponds to the gel strength that reflects the measure of the rigidity of the gel composition. The storage modulus of the gel composition of the present disclosure is in the range of 1 to 1000 Pa, but is not limited thereto.

[0040] The term "viscosity" of the gel disclosed herein corresponds to a measure of its resistance to deformation at a given rate. It corresponds to the "thickness" of the gel and is in the range of 1 to 10 5 cP, but is not limited thereto.

[0041] The term "piezoelectric generator" refers to a power generation device that operates on the principle of piezoelectricity and retains the ability to convert mechanical energy. For example, the vibration of a piezoelectric material is converted into electrical energy. In the devices disclosed herein, the piezoelectric generator generates acoustic vibrations to induce shear thinning of the nanostructure or nanocomposite or gel.

[0042] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present disclosure, but the preferred methods and materials are described herein. All publications mentioned herein are incorporated herein by reference.

[0043] As discussed in the background art, DH becomes a more dominant obstacle and may be associated with both physical and mental problems for patients. Furthermore, it may have a negative effect on the quality of a person's life, especially with regard to dietary choices, optimal dental hygiene, and maintenance of the aesthetic aspect.

[0044] Most of the conventional pharmaceuticals or methods developed for the prevention or suppression of DH have always been short-term treatment approaches based on the sealing of exposed dentinal tubules. In such cases, DH recurs as soon as the coating or sealing material peels off from the sealed tubules. Nevertheless, more advanced treatment strategies available in the art are based on nerve impulse interference techniques. However, there is still a need for a reliable treatment strategy for DH.

[0045] The present disclosure relates to nanostructures, nanocomposites, gel compositions, oral healthcare devices, and methods for preparing them, respectively. Different from the conventional agents aiming to temporarily seal the sensitive sites, the nanostructures disclosed herein serve as more than a permanent solution to the problem of DH. The nanostructures disclosed herein navigate to the dentinal tubules, block the passageways, prevent nerve impulse signals from moving from the sensitive sites to the pulp, thereby preventing the occurrence of DH / pain. Further, calcium in the nanostructures triggers bone growth in these exposed dentins, thereby forming a more permanent barrier. Strontium doping desensitizes the nerve endings, thereby substantially reducing pain. The nanostructures can further be combined with additives such as calcium oxide together with calcium silicate, giving the ability to form bonding blocks in the tubules. The nanostructures disclosed herein also have the ability to regenerate, causing the repair of calcified tissues through triggering the regenerative cell signaling process. Together with their regenerative abilities, they can be remotely homed towards the areas affected by the induced electromagnetic fields generated from mobile terminals due to their inherent magnetic properties. With these characteristics, the said nanostructures can be aimed at the regeneration and repair of calcified tissues such as bone, ligament, and teeth.

[0046] The present disclosure should not be limited to the scope according to the specific embodiments described herein, which are intended for illustration only. Functionally equivalent products, compositions, and methods are clearly within the scope of the disclosure described herein.

[0047] In one embodiment of the present disclosure, a nanostructure comprising 50 to 80% (w / w) of a magnetic material and 20 to 50% (w / w) of calcium silicate, wherein magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, and the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 In one embodiment of the present disclosure, a nanostructure comprising 60 to 70% (w / w) of a magnetic material and 25 to 40% (w / w) of calcium silicate, wherein magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, and the nanostructure has a particle size in the range of 100 to 450 nm; 1 μm 2 ~100 μm 2 In one embodiment of the present disclosure, a nanostructure comprising 50 to 80% (w / w) of a magnetic material and 20 to 50% (w / w) of calcium silicate, wherein magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, and the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm

[0048] ~100 μm 2 In one embodiment of the present disclosure, a nanostructure comprising 50 to 80% (w / w) of a magnetic material and 20 to 50% (w / w) of calcium silicate, wherein magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, and the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm surface area; and pore diameters in the range of 2 nm to 20 nm, and the nanostructure includes shapes selected from spheres, ellipsoids, dumbbell-shaped connected spheres, multiple connected spheres, chains, rods, spirals, or combinations thereof. In another embodiment of the present disclosure, the nanostructure is spherical.

[0049] In one embodiment of the present disclosure, a nanostructure comprising 50 to 80% (w / w) of a magnetic material and 20 to 50% (w / w) of calcium silicate, wherein magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, and the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2The surface area in the range of; and having a pore diameter in the range of 2 nm to 20 nm, a nanostructure is provided, wherein the magnetic material is selected from iron, iron oxide, nickel, nickel oxide, cobalt, cobalt oxide, or a combination thereof. In another embodiment of the present disclosure, the magnetic material is iron or iron oxide.

[0050] In one embodiment of the present disclosure, a nanostructure comprising 50 to 80% (w / w) of a magnetic material and 20 to 50% (w / w) of calcium silicate, wherein the magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, the nanostructure having a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 The surface area in the range of; and having a pore diameter in the range of 2 nm to 20 nm, a nanostructure is provided, wherein the core has a particle size in the range of 5 to 50 nm. In another embodiment of the present disclosure, the core has a particle size in the range of 10 to 45 nm.

[0051] In one embodiment of the present disclosure, a nanostructure comprising 50 to 80% (w / w) of a magnetic material and 20 to 50% (w / w) of calcium silicate, wherein the magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, the nanostructure having a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 The surface area in the range of; and having a pore diameter in the range of 2 nm to 20 nm, a nanostructure is provided, wherein the nanostructure has a zeta potential in the range of -20 to -40 mV. In another embodiment of the present disclosure, the nanostructure has a zeta potential in the range of -25 to -35 mV.

[0052] In one embodiment of the present disclosure, a nanostructure comprising 50 to 80% (w / w) of a magnetic material and 20 to 50% (w / w) of calcium silicate, wherein the magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, the nanostructure having a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2a surface area in the range of; and having a pore size in the range of 2 nm to 20 nm, wherein the nanostructure has a zeta potential in the range of -20 to -40 mV, and the nanostructure includes a shape selected from a sphere, an ellipsoid, a dumbbell-shaped connected sphere, a plurality of connected spheres, a chain, a rod, a helix, or a combination thereof, and the nanostructure treats tooth hypersensitivity and triggers bone regeneration and growth, a nanostructure is provided.

[0053] In one embodiment of the present disclosure, a nanostructure comprising 50 to 80% (w / w) iron or iron oxide and 20 to 50% (w / w) calcium silicate, wherein the iron or iron oxide forms the core of the nanostructure and the calcium silicate forms the shell of the nanostructure, and the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 a surface area in the range of; and having a pore size in the range of 2 nm to 20 nm, and a nanostructure that treats tooth hypersensitivity and triggers bone regeneration and growth is provided.

[0054] In one embodiment of the present disclosure, a nanocomposite comprising a) 95 to 99.9% (w / w) of a nanostructure comprising (i) 50 to 80% (w / w) of a magnetic material and (ii) 20 to 50% (w / w) of calcium silicate, and b) 0.1 to 5% (w / w) of an additive selected from calcium oxide, phosphorus, sodium, strontium, phosphate, fluorine, or a combination thereof, wherein the magnetic particles form the core of the nanostructure and the calcium silicate forms the shell of the nanostructure, and the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 a surface area in the range of; and having a pore size in the range of 2 nm to 20 nm, a nanocomposite is provided.

[0055] In one embodiment of the present disclosure, a nano-composite comprising: a) a nanostructure comprising (i) 50 to 80% (w / w) of a magnetic material and (ii) 20 to 50% (w / w) of calcium silicate, the nanostructure being 98 to 99.9% (w / w); and b) 0.1 to 2% (w / w) of an additive selected from calcium oxide, phosphorus, sodium, strontium, phosphate, fluorine, or a combination thereof, wherein the magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, and the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 of surface area; and a pore size in the range of 2 nm to 20 nm. A nano-composite is provided. In another embodiment of the present disclosure, a nano-composite comprising: a) a nanostructure comprising (i) 50 to 80% (w / w) of a magnetic material and (ii) 20 to 50% (w / w) of calcium silicate, the nanostructure being 98.5 to 99.5% (w / w); and b) 0.5 to 1.5% (w / w) of an additive selected from calcium oxide, phosphorus, sodium, strontium, phosphate, fluorine, or a combination thereof, wherein the magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, and the nanostructure has a particle size in the range of 100 to 450 nm; 1 μm 2 ~100 μm 2 of surface area; and a pore size in the range of 4 nm to 18 nm. A nano-composite is provided.

[0056] In one embodiment of the present disclosure, a nano-composite comprising: a) a nanostructure comprising (i) 50 to 80% (w / w) of a magnetic material and (ii) 20 to 50% (w / w) of calcium silicate, the nanostructure being 95 to 99.9% (w / w); and b) 0.1 to 5% (w / w) of an additive selected from calcium oxide, phosphorus, sodium, strontium, phosphate, fluorine, or a combination thereof, wherein the magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, and the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2a surface area in the range of; and a pore size in the range of 2 nm to 20 nm, and a nano - composite is provided, wherein the additive is embedded in calcium silicate in the shell of the nanostructure. In another embodiment of the present disclosure, the additive is calcium oxide embedded in calcium silicate in the shell of the nanostructure.

[0057] In one embodiment of the present disclosure, a nano - composite comprising: a) 95 - 99.9% (w / w) of nanostructures comprising (i) 50 - 80% (w / w) of iron or iron oxide and (ii) 20 - 50% (w / w) of calcium silicate; and b) 0.1 - 5% (w / w) of an additive selected from calcium oxide, phosphorus, sodium, strontium, phosphate, fluorine, or combinations thereof, wherein the iron or iron oxide forms the core of the nanostructure, the calcium silicate and the additive form the shell of the nanostructure, the nanostructure has a particle size in the range of 50 - 500 nm; 0.01 μm 2 ~100 μm 2 a surface area in the range of; and a pore size in the range of 2 nm to 20 nm, and a nano - composite is provided.

[0058] In one embodiment of the present disclosure, a method for preparing a nanostructure, comprising: (a) mixing an oxidizing agent and a magnetic metal salt in a first solvent, and subsequently adding a base and a silicate precursor to obtain a first mixture; (b) contacting a calcium salt with the first mixture in the presence of a second solvent to obtain a second mixture; and (c) annealing the second mixture at a temperature in the range of 550 - 650 °C to obtain vitreous calcium silicate as the shell of the nanostructure, and subsequently filtering and drying to obtain the nanostructure, wherein the nanostructure has a particle size in the range of 50 - 500 nm; 0.01 μm 2 ~100 μm 2 a surface area in the range of; and a pore size in the range of 2 nm to 20 nm, and a method is provided. In another embodiment of the present disclosure, the step of annealing the second mixture is performed at a temperature in the range of 575 - 625 °C to obtain vitreous calcium silicate as the shell of the nanostructure. In a further embodiment of the present disclosure, the nanostructure has a particle size in the range of 100 - 450 nm; 1 μm 2 ~100 μm 2has a surface area in the range of; and a pore diameter in the range of 4 nm to 18 nm.

[0059] In one embodiment of the present disclosure, a method for preparing a nanostructure disclosed herein, wherein the oxidizing agent is selected from sodium acetate, sodium citrate, or a combination thereof, the magnetic metal salt is selected from iron chloride, iron nitrate, nickel chloride, nickel nitrate, cobalt chloride, cobalt nitrate, or a combination thereof, the first solvent is selected from ethylene glycol, ethanol, water, hydrochloric acid, or a combination thereof, the base is selected from ammonium hydroxide or a metal hydroxide, and the silicate precursor is selected from tetraethyl orthosilicate (TEOS), tetramethyl orthosilicate (TMOS), polyethoxydisiloxane (PEDS), methyltriethoxysilane (MTES), or a combination thereof, is provided.

[0060] In one embodiment of the present disclosure, a method for preparing a nanostructure disclosed herein, wherein the calcium salt is selected from calcium nitrate, calcium carbonate, calcium phosphate, calcium chloride, or a combination thereof, and the second solvent is selected from ethanol, water, or a combination thereof, is provided.

[0061] In one embodiment of the present disclosure, a method for preparing a nanostructure disclosed herein, wherein annealing is performed for a period in the range of 2 to 15 hours, is provided.

[0062] In one embodiment of the present disclosure, a method for preparing a nanostructure, comprising: (a) mixing an oxidizing agent selected from sodium acetate, sodium citrate, or a combination thereof, and a magnetic metal salt selected from iron chloride, iron nitrate, nickel chloride, nickel nitrate, cobalt chloride, cobalt nitrate, or a combination thereof in a first solvent selected from ethylene glycol, ethanol, water, hydrochloric acid, or a combination thereof, and subsequently adding ammonium hydroxide, or a metal hydroxide, and a silicate precursor selected from tetraethyl orthosilicate (TEOS), tetramethyl orthosilicate (TMOS), polyethoxydisiloxane (PEDS), methyltriethoxysilane (MTES), or a combination thereof to obtain a first mixture; (b) contacting a calcium salt selected from calcium nitrate, calcium carbonate, calcium phosphate, calcium chloride, or a combination thereof with the first mixture in the presence of a second solvent selected from ethanol, water, or a combination thereof to obtain a second mixture; and (c) annealing the second mixture at a temperature in the range of 550 to 650 °C to obtain glassy calcium silicate as the shell of the nanostructure, and subsequently filtering and drying to obtain the nanostructure, wherein the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 of surface area; and a pore size in the range of 2 nm to 20 nm. A method is provided.

[0063] In one embodiment of the present disclosure, a method for preparing a nanostructure, comprising: (a) mixing an oxidizing agent and a magnetic metal salt in a first solvent, and subsequently adding a base and a silicate precursor to obtain a first mixture; (b) contacting a calcium salt with the first mixture in the presence of a second solvent to obtain a second mixture; and (c) performing annealing of the second mixture at a temperature in the range of 550 to 650 °C for a period in the range of 2 to 15 hours to obtain glassy calcium silicate as the shell of the nanostructure, and subsequently filtering and drying to obtain the nanostructure, wherein the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2a surface area in the range of; and a pore diameter in the range of 2 nm to 20 nm, and an annealing process includes a temperature increase of 2 to 5 hours, holding at the annealing temperature for 2 to 4 hours, and a temperature decrease of 2 to 5 hours, a method is provided.

[0064] In one embodiment of the present disclosure, a method for preparing a nanostructure, comprising: (a) mixing an oxidizing agent and a magnetic metal salt in a first solvent, and subsequently heating for a period of 8 to 12 hours at a temperature in the range of 200 to 250 °C, and subsequently adding a base and a silicate precursor to obtain a first mixture; (b) contacting a calcium salt with the first mixture in the presence of a second solvent to obtain a second mixture; (c) annealing the second mixture at a temperature in the range of 550 to 650 °C to obtain glassy calcium silicate as the shell of the nanostructure, and subsequently filtering and drying to obtain the nanostructure, the nanostructure having a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 a surface area in the range of; and a pore diameter in the range of 2 nm to 20 nm, a method is provided. In another embodiment of the present disclosure, after mixing the oxidizing agent and the magnetic metal salt in the first solvent, a step of heating for a period of 9 to 11 hours at a temperature in the range of 210 to 240 °C follows.

[0065] In one embodiment of the present disclosure, a method for preparing a nanostructure, comprising: (a) mixing an oxidizing agent selected from sodium acetate, sodium citrate, or a combination thereof with a magnetic metal salt selected from iron chloride, iron nitrate, nickel chloride, nickel nitrate, cobalt chloride, cobalt nitrate, or a combination thereof in a first solvent selected from ethylene glycol, ethanol, water, hydrochloric acid, or a combination thereof, and subsequently adding ammonium hydroxide or a metal hydroxide, and a silicate precursor selected from tetraethyl orthosilicate (TEOS), tetramethyl orthosilicate (TMOS), polyethoxydisiloxane (PEDS), methyltriethoxysilane (MTES), or a combination thereof to obtain a first mixture; (b) contacting a calcium salt selected from calcium nitrate, calcium carbonate, calcium phosphate, calcium chloride, or a combination thereof with the first mixture in the presence of a second solvent selected from ethanol, water, or a combination thereof to obtain a second mixture; (c) annealing the second mixture at a temperature in the range of 550 to 650 °C for a period in the range of 2 to 15 hours to obtain glassy calcium silicate as a shell of the nanostructure, and subsequently filtering and drying to obtain the nanostructure, wherein the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 in surface area; and a pore diameter in the range of 2 nm to 20 nm, and there is provided a method in which the oxidizing agent and the magnetic metal salt are mixed in the first solvent, and then heated at a temperature in the range of 200 to 250 °C for a period of 8 to 12 hours, and then the base and the silicate precursor are added.

[0066] In one embodiment of the present disclosure, a method for preparing a nanocomposite, comprising: a) preparing a nanostructure disclosed herein; and b) immersing the nanostructure in a solution containing a compound selected from calcium oxide, strontium salts, calcium fluoride, sodium fluoride, phosphates, or combinations thereof at a temperature in the range of 20 to 80 °C to obtain a nanocomposite. In another embodiment of the present disclosure, the solution is an aqueous solution containing a compound selected from calcium oxide, strontium salts, calcium fluoride, sodium fluoride, phosphates, or combinations thereof.

[0067] In one embodiment of the present disclosure, a method for preparing a nanocomposite in situ and on demand, comprising: a) preparing a nanostructure disclosed herein; and b) immersing the nanostructure in a solution containing a compound selected from calcium oxide, strontium salts, calcium fluoride, sodium fluoride, phosphates, or combinations thereof at a temperature in the range of 20 to 80 °C to obtain a nanocomposite.

[0068] In one embodiment of the present disclosure, a nanocomposite is provided, wherein a nanostructure having mesoporosity can absorb a trace amount of a compound selected from calcium oxide, strontium salts, calcium fluoride, sodium fluoride, phosphates, or combinations thereof due to the porosity induced by an increase in surface area.

[0069] In one embodiment of the present disclosure, a method for preparing a nanocomposite, comprising: a) (i) mixing an oxidizing agent and a magnetic metal salt in a first solvent, and subsequently adding a base and a silicate precursor to obtain a first mixture; (ii) contacting a calcium salt with the first mixture in the presence of a second solvent to obtain a second mixture; and (iii) annealing the second mixture at a temperature in the range of 550 to 650 °C to obtain glassy calcium silicate as a shell of the nanostructure, followed by filtering and drying to obtain a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2A method for preparing a nanostructure, comprising the step of obtaining a nanostructure having a surface area in the range of and a pore diameter in the range of 2 nm to 20 nm; and b) immersing the nanostructure in a solution containing a compound selected from calcium oxide, strontium salts, calcium fluoride, sodium fluoride, phosphates, or combinations thereof at a temperature in the range of 20 to 80 °C to obtain a nanocomposite. A method is provided.

[0070] In one embodiment of the present disclosure, a) 0.1 to 10% (w / w) of a nanostructure or nanocomposite disclosed herein; b) 0.1 to 20% (w / w) of a hydrogel base; c) 0.1 to 1% (w / w) of a pH adjuster; d) 5 to 10% (w / w) of a wetting agent; e) 80 to 99% (w / w) of a swelling agent; f) 0.1% to 15% (w / w) of calcium oxide; and g) optionally 1 to 5% (w / w) of a stabilizer. A gel is provided. In another embodiment of the present disclosure, a) 0.1 to 4% (w / w) of a nanostructure or nanocomposite disclosed herein; b) 0.1 to 8% (w / w) of a hydrogel base; c) 0.3 to 0.8% (w / w) of a pH adjuster; d) 6.5 to 8.5% (w / w) of a wetting agent; e) 85 to 94% (w / w) of a swelling agent; f) 0.1% to 12% (w / w) of calcium oxide; and f) optionally 1.5 to 4.5% (w / w) of a stabilizer. A gel is provided.

[0071] In one embodiment of the present disclosure, a) 0.1 to 10% (w / w) of a nanostructure or nanocomposite disclosed herein; b) 0.1 to 20% (w / w) of a hydrogel base; c) 0.1 to 1% (w / w) of a pH adjuster; d) 5 to 10% (w / w) of a wetting agent; e) 80 to 99% (w / w) of a swelling agent; f) 0.1% to 15% (w / w) of calcium oxide; g) optionally 1 to 5% (w / w) of a stabilizer; and h) an antibacterial agent. A gel is provided.

[0072] In one embodiment of the present disclosure, a gel, comprising: a) a nanostructure, the nanostructure being a nanostructure comprising 50 to 80% (w / w) of a magnetic material and 20 to 50% (w / w) of calcium silicate, magnetic particles forming the core of the nanostructure, calcium silicate forming the shell of the nanostructure, the nanostructure having a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 a surface area in the range of; and a pore diameter in the range of 2 nm to 20 nm, or a nanocomposite disclosed herein, 0.1 to 10% (w / w); b) 0.1 to 20% (w / w) of a hydrogel base; c) 0.1 to 1% (w / w) of a pH adjuster; d) 5 to 10% (w / w) of a wetting agent; e) 80 to 99% (w / w) of a swelling agent; f) 0.1% to 15% (w / w) of calcium oxide; and g) optionally 1 to 5% (w / w) of a stabilizer. A gel is provided.

[0073] In one embodiment of the present disclosure, a gel, comprising: a) a nanostructure disclosed herein, or I) (i) 50 to 80% (w / w) of a magnetic material forming the core of the nanostructure and (ii) 20 to 50% (w / w) of calcium silicate forming the shell of the nanostructure, and II) a nanocomposite comprising 0.1 to 5% (w / w) of an additive selected from phosphorus, sodium, strontium, phosphate, fluorine, or combinations thereof, magnetic particles forming the core of the nanostructure, calcium silicate forming the shell of the nanostructure, the nanostructure having a particle size in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 a surface area in the range of; and a pore diameter in the range of 2 nm to 20 nm, having 95 to 99.9% (w / w), nanostructure, 0.1 to 10% (w / w), b) 0.1 to 20% (w / w) of a hydrogel base; c) 0.1 to 1% (w / w) of a pH adjuster; d) 5 to 10% (w / w) of a wetting agent; e) 80 to 99% (w / w) of a swelling agent; f) 0.1% to 15% (w / w) of calcium oxide; and g) optionally 1 to 5% (w / w) of a stabilizer. A gel is provided.

[0074] In one embodiment of the present disclosure, a gel comprising: a) 0.1 to 10% (w / w) of the nanostructures or nanocomposites disclosed herein; b) 0.1 to 20% (w / w) of a hydrogel base; c) 0.1 to 1% (w / w) of a pH adjuster; d) 5 to 10% (w / w) of a wetting agent; e) 80 to 99% (w / w) of a swelling agent; f) 0.1% to 15% (w / w) of calcium oxide; and g) optionally 1 to 5% (w / w) of a stabilizer, wherein the hydrogel base is selected from polyacrylic acid, diutan gum, an acrylic acid alkyl cross-polymer, a poloxamer compound, or a combination thereof; the pH adjuster is selected from triethanolamine, disodium tetraborate, TrisBase, or a combination thereof; the wetting agent is selected from glycerin, lecithin, propylene glycol, water, or a combination thereof; the swelling agent is selected from ethanol, water, or a combination thereof; and the stabilizer is selected from xanthan gum, gelatin, starch, glyceryl agar, or a combination thereof, is provided.

[0075] In one embodiment of the present disclosure, a gel comprising: a) 0.1 to 10% (w / w) of the nanostructures or nanocomposites disclosed herein; b) 0.1 to 20% (w / w) of a hydrogel base; c) 0.1 to 1% (w / w) of a pH adjuster; d) 5 to 10% (w / w) of a wetting agent; e) 80 to 99% (w / w) of a swelling agent; f) 0.1% to 15% (w / w) of calcium oxide; and g) optionally 1 to 5% (w / w) of a stabilizer, having a viscosity in the range of 1 to 10 5 cP and a storage modulus in the range of 1 to 1000 Pa is provided. In another embodiment of the present disclosure, the gel has a viscosity in the range of 1 to 500 cP and a storage modulus in the range of 1 to 500 Pa.

[0076] In one embodiment of the present disclosure, a method for preparing a gel, comprising: a) mixing a nanostructure or nanocomposite disclosed herein with a hydrogel base comprising a swelling agent to obtain a first solution; b) adding a pH adjuster and calcium oxide powder to the first solution to obtain a second solution; and c) adding a wetting agent and optionally a stabilizer to obtain the gel.

[0077] In one embodiment of the present disclosure, a method for preparing a gel, comprising: a) mixing a nanostructure or nanocomposite disclosed herein with a hydrogel base selected from polyacrylic acid, diutan gum, an acrylic acid alkyl cross-polymer, a poloxamer compound, or a combination thereof, and a swelling agent selected from ethanol, water, or a combination thereof to obtain a first solution; b) adding a pH adjuster selected from triethanolamine, disodium tetraborate, TrisBase, or a combination thereof, and calcium oxide powder to the first solution to obtain a second solution; c) adding a stabilizer selected from xanthan gum, gelatin, starch, agar glyceride, or a combination thereof, and a wetting agent selected from glycerin, lecithin, propylene glycol, or a combination thereof to obtain a gel.

[0078] In one embodiment of the present disclosure, a method for treating dentin hypersensitivity, comprising administering a nanostructure or nanocomposite or gel disclosed herein to a subject suffering from dentin hypersensitivity.

[0079] In one embodiment of the present disclosure, a method for administering a nanostructure or nanocomposite or gel disclosed herein, comprising applying, propelling, and positioning a nanostructure or nanocomposite or gel disclosed herein into infected dentinal tubules using a magnetic cap. In another embodiment of the present disclosure, the method comprises applying, propelling, and positioning a nanostructure or nanocomposite or gel disclosed herein into infected dentinal tubules using a magnetic clip.

[0080] In one embodiment of the present disclosure, a device comprising a nanostructure or nanocomposite or gel disclosed herein and a magnetic cap is provided.

[0081] In one embodiment of the present disclosure, there is provided a device comprising a nanostructure or nanocomposite or gel and a magnetic cap disclosed herein, and further comprising a piezoelectric generator for inducing acoustic excitation. In another embodiment of the present disclosure, the magnetic cap or clip generates acoustic vibrations to induce shear thinning of the nanostructure or nanocomposite or gel in addition to the piezoelectric generator.

[0082] In one embodiment of the present disclosure, there is provided a device comprising a nanostructure or nanocomposite or gel and a magnetic cap disclosed herein, wherein the magnetic cap or clip comprises a simple permanent magnet or an electromagnetic coil.

[0083] In one embodiment of the present disclosure, there is provided the use of a nanostructure or nanocomposite or gel disclosed herein.

[0084] In one embodiment of the present disclosure, there is provided a nanostructure or nanocomposite or gel disclosed herein for use in the treatment of tooth hypersensitivity and as a trigger for bone regeneration and growth.

[0085] Although the subject matter has been described in considerable detail with respect to certain specific embodiments thereof, other embodiments are possible. Accordingly, the spirit and scope of the present disclosure should not be limited to the descriptions of the embodiments contained herein.

Examples

[0086] The present disclosure is illustrated here by way of examples, which are intended to illustrate the implementation of the disclosure and are not intended to be construed restrictively so as to imply any limitation on the scope of the disclosure. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Methods and materials similar or equivalent to those described herein can be used in the practice of the methods and compositions of the present disclosure, but exemplary methods, devices, and materials are described herein. It should be understood that the present disclosure is not limited to the specific methods and experimental conditions described, which may be applicable.

[0087] (Example 1) Nanostructure For the purpose of long-term prevention or suppression of DH, the present disclosure discloses a nanostructure that limits the passage of dentinal tubules, thereby facilitating the interference of nerve impulse transmission from the exposed dentin surface to the pulp associated with pain. The nanostructure of the present disclosure has an elemental composition in the form of a core-shell structure in which the core becomes magnetic due to the presence of a magnetic material. The magnetic core enables the targeted delivery of particles into the dentinal tubules using an external magnetic force. The nanostructures disclosed herein bring about the prevention or healing of DH by triggering bone regeneration and growth.

[0088] The core of the nanostructure is composed of a magnetic material such as iron, iron oxide, nickel, cobalt, or a combination thereof having 50 to 80 weight percent, and the shell is composed of calcium silicate having 20% to 50 weight percent. The nanostructure has a particle size (diameter) in the range of 50 to 500 nm; 0.01 μm 2 ~100 μm 2 in the range of surface area; and a pore diameter in the range of 2 nm to 20 nm. The surface charge (zeta potential) of the nanostructure exists between -20 and -40 mV, has a large negative number, and provides stability against aggregation for them. The negative charge prevents magnetic aggregation due to the repulsive action based on the same inherent charge and, due to the superparamagnetic behavior, can reverse magnetic aggregation even if it occurred when the magnetic field was removed.

[0089] Nevertheless, the nanostructures disclosed herein have a spherical shape including an inner core and an outer shell structure, and it can be contemplated that such a design or composition may be of different shapes such as an ellipsoid, an hourglass-shaped connected sphere, a plurality of connected spheres, a chain, a rod, a helix, or a combination thereof. Further, the present disclosure also uses magnetic materials selected from the group including iron, iron oxide, nickel, nickel oxide, cobalt, cobalt oxide, or combinations thereof to form various forms of the nanostructures disclosed herein. All such possible forms fall within the scope of the disclosure made herein. For example, the nanostructures disclosed herein can also be developed in the form of a cookie-like structure in which magnetic core particles are embedded in a calcium silicate matrix.

[0090] (Example 2) Preparation of Nanostructures For the purposes of the present disclosure, nanostructures were developed using magnetite (iron oxide, Fe 3 O 4 ) nanocrystals. First, 20 ml of ethylene glycol (the first solvent) was placed in a Teflon tube, 1.2 gm of sodium acetate (oxidizing agent) was added thereto, and subsequently 0.2 gm of sodium citrate dihydrate (oxidizing agent) was added. Subsequently, 1.080 gm of iron(III) chloride hexahydrate (the magnetic metal (iron) salt gives 69.9% iron) was added to the ethylene glycol solution, and then the Teflon tube was placed in an autoclave chamber and placed in a high-temperature air bath at 210 °C for 10 hours.

[0091] After 10 hours of the high-temperature air bath ended, the Teflon tube sample was purified using centrifugation at 5000 rpm for 5 minutes. Subsequently, the centrifuged sample was suspended in water, and then centrifuged three times in water and subsequently three times in ethanol. After the centrifugation step, next, the sample was suspended in 50 ml of ethanol, and from this, 10 ml of the sample was taken and centrifuged at 5000 rpm for 5 minutes. Then, the centrifuged sample was suspended in 10 ml of deionized (DI) water. During this time, 0.425 ml of 38% HCl was added to 40 ml of DI water to prepare a 0.1 M HCl solution (the first solvent), and then this was added to the 10 ml of centrifuged sample in the last step. Then, the mixture with a 10-minute duration was treated with ultrasound, followed by centrifugation at 5000 rpm for 5 minutes twice, then suspended in a 10 ml ethanol solution, and 5 ml of this sample was added to 37.5 ml of ethanol, and then this was mixed with 3.5 ml of ammonium hydroxide (base) measured using a small volumetric flask due to its low viscosity. Then, the mixture from the last step (i.e., base + the first solvent) was added to 47.5 ml of the centrifuged sample (a solution of an oxidizing agent and a magnetic metal salt in the first solvent suspended in 50 ml of ethanol), then placed in an ultrasonic bath, and subsequently 0.1 ml of tetraethyl orthosilicate (TEOS) solution (silicate precursor) was added to obtain a first mixture. After adding the TEOS solution, the first mixture was treated with ultrasound for a 90-minute duration. During the ultrasound treatment, ice cubes were added every 5 minutes to maintain the initial temperature. After the ultrasound treatment, the sample was centrifuged three times in water and subsequently three times in ethanol with ultrasound treatment. (the second solvent).

[0092] Next, the first mixture was suspended in 10 ml of ethanol, 5 ml of this solution was taken in a beaker, and mixed with 0.13 gm of calcium nitrate tetrahydrate (the calcium salt gives 46.5% calcium silicate) to obtain a second mixture. The second mixture was then sonicated for 55 hours, adding cubed ice every 5 minutes to maintain room temperature. After sonication, the sample was placed on a magnet to remove the excess calcium nitrate. After magnetic separation, 2.5 ml of ethanol (the second solvent) was added to the magnetically separated sample, and it was placed in an oven under convection conditions at 40 °C until the ethanol solution evaporated. After the evaporation of ethanol was complete, the resulting second mixture was placed in a Lindberg furnace and annealed at 600 °C for 3 hours. The temperature was continuously increased at a rate of 2 °C per minute (for 5 hours). After completion of the cycle, the sample was taken out of the furnace and the powder was discarded from the quartz crucible. The sample was then suspended in water and centrifuged three times to obtain the nanostructures.

[0093] In the process as detailed above, magnetite nanocrystals were prepared and subsequently glassy calcium silicate was formed as the shell of the nanostructures. Calcium nitrate tetrahydrate was used to inject calcium into the iron-silicate core-shell.

[0094] Increasing the weight percentage of calcium silicate was observed to result in the formation of calcium nodules and, consequently, aggregation of the nanostructures. Thus, increasing the weight percentage of calcium silicate beyond 20 - 50% in the nanostructures was not possible without substantial changes to the geometry and size. Therefore, nanostructures having more than 50% calcium silicate in the composition with similar geometry and size as disclosed herein did not exhibit the desired properties as shown by the nanostructures of the present disclosure.

[0095] Overall, a particle size in the range of 50 - 500 nm; 0.01 μm 2 ~100 μm 2The surface area in the range of; and the pore diameter in the range of 2 nm to 20 nm can be inferred to be a decisive aspect of the nanostructures disclosed in this specification. High-angle annular dark-field images (HAADF) of scanning transmission electron microscopy analysis show that the particle size is 250 nm (Figs. 1 and 2), the pore diameter is about 10 nm, and the surface area is in the range of 1 to 100 μm 2 showed that it is in the range. Energy-dispersive X-ray spectroscopy analysis (Fig. 3) further confirmed the presence of magnetic particles (iron) and calcium silicate particles in the nanostructures.

[0096] Furthermore, the various forms of the nanostructures disclosed in this specification contain 50 to 80% (w / w) of magnetic material and 20 to 50% (w / w) of calcium silicate. The magnetic particles form the core of the nanostructures, and calcium silicate forms the shell of the nanostructures.

[0097] (Example 3) Nanostructure-based nanocomposites According to the disclosure in this specification, the nanocomposites contain 95 to 99.9% (w / w) of nanostructures (prepared in Example 2); and 0.1 to 5% (w / w) of additives selected from calcium oxide, phosphorus, sodium, strontium, phosphoric acid, fluorine, or combinations thereof. In particular, the nanocomposites were obtained by adding the nanostructures obtained in Example 2 using calcium oxide dissolved in water. The addition of such additives enabled the on-demand formation of nanocomposites inside microscopic channels such as dentinal tubules.

[0098] (Example 4) Preparation of nanocomposites The method for preparing the nanocomposite disclosed in this specification includes: a) a step of preparing nanostructures (as prepared in Example 2 above), and b) a step of immersing the nanostructures in a calcium oxide solution. The process of physical adsorption was promoted by using ambient temperature conditions raised in the range of 20 to 80°C. The calcium oxide solution reacted with the nanostructures to form a cement-like material in situ. The addition of such additives enabled the formation of the nanocomposite as needed inside microscopic flow channels such as dentinal tubules.

[0099] In this example, calcium oxide was used for physical adsorption in the nanostructures, but the additive can be selected from strontium salts, sodium fluoride, calcium fluoride, phosphates, fluorides, or combinations thereof, and can also be prepared by using various surface absorption methods instead of physical adsorption for the same purpose.

[0100] (Example 5) Nanostructure-based gel composition This example relates to a method for preparing a gel composition containing nanostructures or nanocomposites, and a topical gel used in dental healthcare for the prevention or treatment of DH. The present disclosure provides a carbomer-triethanolamine-based gel containing trace amounts of strontium and fluoride salts that help reduce dentinal pain. The gel composition contains 50 ml of distilled water (swelling agent), 5 mg of calcium oxide powder, 0.01% (w / w) of 3% hydrogen peroxide (antibacterial agent), 5.2% (w / w) of anhydrous glycerin (humectant), 0.2% (w / w) of carbomer 980 or other carbomer compounds (hydrogel-based), 0.15 ml (0.3% (w / w)) of triethanolamine (pH adjuster), 0.5% (w / w) of calcium oxide, and 99.5% (w / w) of nanostructures (prepared in Example 2), including a 2% (w / w) nanocomposite, together with a 0.5% (w / w) additive respectively selected from calcium oxide (0.1 mg / ml), calcium fluoride, or strontium chloride (additive). The gel disclosed in this specification had a viscosity of 5000 cP and a storage modulus of 38.3 Pa (at a shear rate of 1 radian / second).

[0101] (Example 6) (Preparation of Nanostructure-Based Gel Composition) This example relates to a method for preparing a nanostructure-based gel composition disclosed in Example 5. The process included the steps of mixing 2% (w / w) nanostructures prepared in Example 2 with a 0.2% (w / w) hydrogel base, and subsequently mixing with 50 ml of distilled water (swelling agent) to obtain a first solution. To the first solution, 5 mg of calcium oxide powder and 0.15 ml of triethanolamine (0.3% (w / w)) (pH adjuster) were added to obtain a second solution. After the preparation of the second solution, 5.2% (w / w) anhydrous glycerin (humectant) was added to obtain a gel. Further, 0.01% (w / w) of 3% hydrogen peroxide was added to the gel to impart antibacterial properties.

[0102] (Example 7) (Nanostructure-Based Device) To facilitate the application of the nanostructures or nanocomposites or gel compositions disclosed herein, the present disclosure provides a device comprising a nanostructure or nanocomposite or gel and a magnetic cap. The device disclosed herein further includes a piezoelectric generator for inducing acoustic excitation.

[0103] According to the present disclosure, the magnetic cap or clip includes a simple permanent magnet or electromagnetic coil that regulates the targeted movement of the nanostructures under a magnetic field. For the purpose of treating or preventing DH of the subject, the gel composition is applied covering the hypersensitive area (exposed dentin), and the magnetic cap or clip is placed on the opposite side of the affected area of the tooth / dental arch (maxilla / mandible). The magnetic cap or clip pulls the nanostructures present in the gel suspension and directs them towards the exposed dentinal tubules for 10 - 15 minutes, during which the head of the subject is stabilized in a neutral rest position to improve the effectiveness of the treatment.

[0104] When applied to an affected tooth, the nanostructure navigates into the dentinal tubules, forms a barrier in the middle, and interrupts the movement of nerve impulses as shown in Figure 4. After the treatment session, the device is removed and the remaining gel is wiped off the target tooth. The subject may need to undergo subsequent sessions for improvement of the effectiveness of the treatment. Figure 4 shows a capture of a microscopic view representing distinct tubular barriers by nanostructures at two different positions. Similarly, nanostructures containing iron together with calcium silicate were mixed with a calcium oxide solution and applied to the affected tooth to form a nano - composite in - situ on - demand. Figure 5 shows a microscopic image of the formed nano - composite, indicating the formation of cement blocks in the dentinal tubules. This confirmed the ability of the nano - composite of the present disclosure to form a junction block of the passageway, thereby forming a permanent barrier in the dentinal tubules and preventing hypersensitivity and the accompanying pain.

[0105] Advantages of the present disclosure The foregoing implementation examples described for the present subject matter and their equivalents have many advantages including those described.

[0106] The present disclosure discloses nanostructures, nano - composites, gel compositions, oral healthcare devices, and methods for preparing them respectively. Different from conventional agents that are swept away from sensitive sites after a certain period, the nanostructures disclosed herein navigate into the dentinal tubules, block the passageways, thereby restricting nerve impulse signals from the exposed dentin to the pulp, and as a result eliminating DH / pain. Further, calcium in the nanostructures is said to trigger bone growth in these exposed dentins, thus forming a more permanent barrier. Strontium doping desensitizes nerve endings, thereby substantially reducing pain.

[0107] The nanostructures disclosed herein also have the ability to regenerate and cause the repair of calcified tissues by triggering the regenerative cell signaling process. Together with their regenerative ability, they can be remotely homed towards the area affected by the induced electromagnetic field generated from a mobile terminal due to their inherent magnetic properties. With these characteristics, the nanostructures can be aimed at the regeneration and repair of calcified tissues such as bone, ligament and teeth.

Claims

1. A nanostructure comprising 50 to 80% (w / w) of a magnetic material and 20 to 50% (w / w) of calcium silicate, wherein magnetic particles form the core of the nanostructure and calcium silicate forms the shell of the nanostructure, The nano-structure has a particle size in the range of 50 to 500 nm; 0.01 μm ２ to 100 μm ２ of surface area; and a pore diameter in the range of 2 nm to 20 nm, a nano-structure.

2. The nanostructure according to claim 1, comprising a shape selected from a sphere, an ellipsoid, dumbbell-shaped connected spheres, a plurality of connected spheres, a chain, a rod, a helix, or a combination thereof.

3. The nanostructure according to claim 1, wherein the magnetic material is selected from iron, iron oxide, nickel, nickel oxide, cobalt, cobalt oxide, or a combination thereof.

4. The nanostructure according to claim 1, wherein the core has a particle size in the range of 5 to 50 nm.

5. The nanostructure according to claim 1, having a zeta potential in the range of -20 to -40 mV.

6. The nanostructure according to claim 1, which cures tooth hypersensitivity and triggers bone regeneration and growth.

7. A nanocomposite, a) 95 to 99.9% (w / w) of a nanostructure comprising (i) 50 to 80% (w / w) of a magnetic material and (ii) 20 to 50% (w / w) of calcium silicate, and b) 0.1 to 5% (w / w) of an additive selected from calcium oxide, phosphorus, sodium, strontium, phosphate, fluorine, or a combination thereof comprising, Magnetic particles form the core of the nanostructure, calcium silicate forms the shell of the nanostructure, and the nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm ２ to 100 μm ２ a surface area in the range of; and a pore diameter in the range of 2 nm to 20 nm, a nanocomposite.

8. The nanocomposite according to claim 7, wherein the additive is embedded in the calcium silicate in the shell of the nanostructure.

9. The nanocomposite according to claim 7, wherein calcium oxide is embedded in the calcium silicate in the shell of the nanostructure.

10. A method for preparing the nanostructure according to claim 1, comprising: a. mixing an oxidizing agent and a magnetic metal salt in a first solvent, and subsequently adding a base and a silicate precursor to obtain a first mixture; b. contacting a calcium salt with the first mixture in the presence of a second solvent to obtain a second mixture; c. annealing the second mixture at a temperature in the range of 550 to 650 °C to obtain vitreous calcium silicate as the shell of the nanostructure, and subsequently filtering and drying to obtain the nanostructure comprising, The nanostructure has a particle size in the range of 50 to 500 nm; 0.01 μm ２ to 100 μm ２ of surface area; and a pore diameter in the range of 2 nm to 20 nm, a method.

11. The oxidizing agent is selected from sodium acetate, sodium citrate, or a combination thereof; the magnetic metal salt is selected from iron chloride, iron nitrate, nickel chloride, nickel nitrate, cobalt chloride, cobalt nitrate, or a combination thereof; the first solvent is selected from ethylene glycol, ethanol, water, hydrochloric acid, or a combination thereof; the base is selected from ammonium hydroxide or a metal hydroxide; the silicate precursor is selected from tetraethyl orthosilicate (TEOS), tetramethyl orthosilicate (TMOS), polyethoxydisiloxane (PEDS), methyltriethoxysilane (MTES), or a combination thereof. The method according to claim 10.

12. The calcium salt is selected from calcium nitrate, calcium carbonate, calcium phosphate, calcium chloride, or a combination thereof; the second solvent is selected from ethanol, water, or a combination thereof. The method according to claim 10.

13. Annealing is carried out for a period in the range of 2 to 15 hours. The method according to claim 10.

14. The oxidizing agent and the magnetic metal salt are mixed in the first solvent, and then heated at a temperature in the range of 200 to 250 °C for a period of 8 to 12 hours, and then the base and the silicate precursor are added. The method according to claim 10.

15. A method for preparing the nanocomposite according to claim 7, comprising: a) a step of preparing the nanostructure according to claim 10; and b) immersing the nanostructure in a solution containing a compound selected from calcium oxide, strontium salt, calcium fluoride, sodium fluoride, phosphate, or a combination thereof at a temperature in the range of 20 to 80 °C to obtain a nanocomposite.

16. a. 0.1 to 10% (w / w) of the nanostructure according to claim 1 or the nanocomposite according to claim 7, b. 0.1 to 20% (w / w) of a hydrogel base, c. 0.1 to 1% (w / w) of a pH adjuster, d. 5 to 10% (w / w) of a wetting agent, e. 80 to 99% (w / w) of a swelling agent, f. 0.1% to 15% (w / w) of calcium oxide, and g. Optionally 1 to 5% (w / w) of a stabilizer A gel comprising.

17. The gel according to claim 16, further comprising an antibacterial agent.

18. The hydrogel base is selected from polyacrylic acid, diutan gum, alkyl acrylate crosspolymer, poloxamer compound, or a combination thereof; the pH adjuster is selected from triethanolamine, disodium tetraborate, Tris Base, or a combination thereof; the wetting agent is selected from glycerin, lecithin, propylene glycol, or a combination thereof; the swelling agent is selected from ethanol, water, or a combination thereof; the stabilizer is selected from xanthan gum, gelatin, starch, glyceryl agar, or a combination thereof, the gel according to claim 16.

19. 1 to 10 ５ The gel according to claim 16, having a viscosity in the range of cP and a storage elastic modulus in the range of 1 to 1000 Pa.

20. A method for preparing the gel according to claim 16, comprising: a. mixing the nanostructure according to claim 1 or the nanocomposite according to claim 7 with a hydrogel base and a swelling agent to obtain a first solution; b. adding a pH adjuster and calcium oxide powder to the first solution to obtain a second solution; c. adding a wetting agent and optionally a stabilizer to obtain a gel A method comprising.

21. A method for treating tooth hypersensitivity, comprising administering to a subject suffering from tooth hypersensitivity the nanostructure according to claim 1, the nanocomposite according to claim 7, or the gel according to claim 16.

22. A method for administering the nanostructure according to claim 1, the nanocomposite according to claim 7, or the gel according to claim 16, comprising applying, propelling, and positioning the nanostructure according to claim 1, the nanocomposite according to claim 7, or the gel according to claim 16 to infected dentinal tubules using a magnetic cap.

23. A device comprising the nanostructure according to claim 1, the nanocomposite according to claim 7, or the gel according to claim 16 and a magnetic cap.

24. The device according to claim 23, further comprising a piezoelectric generator that induces acoustic excitation.

25. The method according to claim 22 or the device according to claim 23, wherein the magnetic cap comprises a simple permanent magnet or an electromagnetic coil.

26. Use of the nanostructure according to claim 1, the nanocomposite according to claim 7, or the gel according to claim 16.

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