ES2409330T3 - Tooth whitening composition - Google Patents

Abstract

Tooth whitening composition in the form of a pre-formed film for application on the surface of the teeth, said film being formed by at least one whitening agent together with at least one film-forming material, characterized in that said film is soluble in water and is not associated with any support material, the tooth whitening composition further comprising a flavoring ingredient.

Description

Teeth whitening composition.

The present invention relates to a tooth whitening composition.

It is well known that teeth stain as a result of daily life. For example, exposure to tobacco, tea or coffee stains teeth. Obviously, the more teeth are exposed to these materials, the greater the magnitude of staining / discoloration of the teeth.

In recent years there is great interest in the appearance and the white of the teeth has become an important issue for many people. As a result, many dentifrices advertise that they have a tooth whitening effect. In general, these dentifrices are abrasive and, due to the short exposure time, have a limited effect.

EP-511781 describes a liquid polymer composition for teeth whitening. The liquid composition is applied on the teeth, forming on them a film.

More recently, chemical formulations that have a tooth whitening effect have been proposed. For example, WO 01/68045 describes multilayer patches with peroxide as a bleaching active agent. The active material is associated with a support or support material that is removed from the teeth after treatment.

WO 03/015656 refers to a strip providing a substance for oral care. The oral care substance may be a bleaching agent and the supply strip is removed from the surface of the teeth after treatment.

These systems increase the contact time between the active material and stained teeth. However, the support material, which protects the gum area from overexposure to the active material, can be uncomfortable for the user and difficult to remove once the treatment is finished. Therefore, it would be desirable to provide an effective tooth whitening composition gentle enough not to damage the tissue around the teeth and that can be applied without the need for any support material.

In accordance with the present invention, there is provided a tooth whitening composition comprising at least one bleaching agent together with at least one film-forming material and a flavoring agent, characterized in that the composition is in the form of a preformed water soluble film and why not It is associated with any support material.

The composition of the present invention is provided in the form of a water soluble film and which does not require any support material during use. In addition, the composition self-adheres to the teeth. Typically the composition adheres to the teeth in 0.5 to 2.0 minutes.

The film can be arranged in a way that corresponds, to the greatest extent possible, with the shape of the area on which it is to be applied, for example a strip for application on the incisors.

The concept "water soluble" refers to a material that dissolves in water forming a solution.

The film is applied to the surface of the teeth and, upon contact with the saliva, begins to dissolve. The film is such that the solution occurs in a time interval ranging from about 30 seconds to about 120 minutes. Advantageously, this slow dissolution allows the film, and consequently the active ingredients contained therein, to come into contact with the teeth for a sufficient time to whiten the teeth.

Surprisingly, after dissolution on the teeth a coating remains for hours after use, producing a smooth long-term effect. The user does not perceive the presence of this coating.

Obviously, the absence of a support material provides greater ease of use than currently available products, since no support material must be removed from the surface of the teeth after treatment. It also makes the product more convenient to use and allows the user to speak clearly while using the product.

In addition, the amount of active ingredient to which the user is exposed is controlled, unlike the prior art systems, where the user can ignore the instructions and maintain the support material, and consequently the active material, in contact with the teeth for too long. This is not a problem in the case of the compositions of the present invention.

Preferably, the bleaching agent is based on peroxide. It is possible to use any peroxide compound, those peroxides that include hydrogen peroxide and / or urea peroxide being especially preferred.

The bleaching agent preferably constitutes between 0.1% and 50% w / w of the total composition.

Advantageously, the use of only peroxide as a bleaching agent results in a composition that is especially stable and, therefore, has a long shelf life, unlike bleaching agents, for example perchlorates, present in tooth whitening compositions. known.

It is well known that teeth whitening agents cause tooth sensitivity. In general, this sensitivity is experienced at certain times. Surprisingly, it has been shown that the bleaching composition of the present invention induces less dental sensitization than expected and considerably lower than that of comparable products currently on the market.

Accordingly, a tooth whitening composition is provided as described herein that does not sensitize the teeth.

The film-forming material is such that it is soluble in water. The types of film-forming materials described herein can be used alone or in combination, so that the film can have a degree of water solubility.

The film-forming materials of the present invention are polymeric materials and their selection is limited only by the requirement to impart water solubility to the film. Suitable film-forming materials include any of the following materials, alone or in combination: polysaccharides, polyvinyl alcohol, polyvinyl pyrrolidone, polyurethane and polymers based on polyacrylic acid, such as CARBOPOL® and derivatives thereof.

Especially preferred film-forming materials for use with the present invention are those derived from cellulose. Particularly preferred water soluble film-forming materials are carboxymethyl cellulose and hydroxyethyl cellulose.

The film-forming material preferably constitutes between 0.1 and 99.9% w / w of the total composition.

Normally, in addition to the bleaching agent, the film preferably comprises any of the following components, alone or in combination: at least one plasticizer and at least one filler.

Plasticizers suitable for use with the present invention include any of the following, alone or in combination: polyalcohols such as glycerol, propylene glycol, polyethylene glycol, sugar syrups such as fructose, maltose, etc.

The plasticizer (s) preferably constitute between 0 and 80% w / w of the total composition.

Loading materials suitable for use with the present invention include, for example, any of the following, alone or in combination: silica, silicones, sodium sulfate, sodium bicarbonate, Pluronic surfactants, fatty acid compounds, sodium lauryl ether sulfate and ethyl cellulose. In addition to acting as a loading material, these materials can be chosen to accelerate or slow down the solution.

Preferably the filler material constitutes between 0 and 80% w / w of the total composition.

The composition described herein comprises a flavoring ingredient and may comprise additional ingredients, such as stabilizers, humectants, thickeners, preservatives and dyeing technology auxiliaries (to color the composition, not the teeth), pigments (to color the teeth) and mixtures thereof. Technological aids include silicone-based components, such as dimethicone.

It is intended that the composition of the present invention be used to provide other benefits to the teeth / mouth. For example, the composition may further comprise any of the following substances, alone

or in combination: antimicrobial ingredients, anti-plate components, antisarro components, dental cleaning agents, desensitizing agents, herbs, honey (provides sweetness and has antimicrobial properties), medications, appetite suppressants and biologically active compounds.

In accordance with another aspect of the present invention, the use of a tooth whitening composition as described above to reduce discoloration of the teeth is provided.

In accordance with another aspect of the present invention, there is provided a method for the production of a tooth whitening composition as described above which includes the steps of: preparing an aqueous mixture comprising at least one bleaching agent together with at least a film-forming material, pour said mixture on a substrate and allow the mixture to dry.

The bleaching agent may be included in the film-forming material before being added to the composition.

In an alternative procedure, a suitable film is prepared beforehand and then a bleaching agent is applied on its surface. The bleaching agent can be applied to the film by spraying, pressure and / or thermal transfer or by immersion coating.

Thus, in accordance with another aspect of the present invention, there is provided a method for preparing a tooth whitening composition comprising the steps of: applying a bleaching agent on the surface of a previously prepared film comprising a water soluble film-forming material, thus forming a tooth whitening composition.

5 The substrate on which the composition is arranged may consist of a coated paper, a coated metal or a plastic material.

The composition of the present invention may be available in the form of a multilayer film, the composition comprising for example a layer of water-dispersible film-forming material having a layer of water-soluble film-forming material including a bleaching agent disposed at least on one of its faces . It has to

10 understand that there are many ways to build a layered structure of this type. Thus, combinations of components within each layer and the order in which the layers are in contact with each other are only limited by the compatibility of the components within each layer.

For use, a strip of the film of the present invention can be applied to the teeth every morning and night for 14 days. It could be expected that the application of such a product without any support or reinforcement material

15 would cause irritation or redness of the oral tissues; Surprisingly, the product does not cause such irritation (see Table 2). These applications are well below the guidelines proposed by the SCCNFP (Scientific Committee on Cosmetic and Non Food Products) for exposure to components such as hydrogen peroxide, 50 mg / day.

The invention is described in more detail below only by way of example.

20 Reference Example 1

Material

Quantity (% w / w) Function

Sodium alginate

60% Film forming polymer / thickener

Hydrogen peroxide

7.5% Bleaching agent

Fructose syrup

2% Moisturizer / plasticizer / sweetener

Glycerol

 10% Moisturizer

Sodium pyrophosphate

0.25% Stabilizer

Methylparaben

 0.25% Preservative

Ethyl cellulose

twenty% 2nd film forming agent / filler

In the preparation of this example an additional 3,500% of purified water (80%) and ethanol (20%) are used. The methylparaben dissolves in the water while it is hot and then the mixture cools below 25 ° C. Ethylcellulose is dissolved in ethanol. The aqueous phase and the ethanolic phases are mixed, introduced into a

25 low shear mixer and undergo circulation. At this time the other ingredients (except sodium alginate) are added and mixed for another 30 minutes. Sodium alginate is added slowly to produce a homogeneous mixture.

The resulting polymer solution is placed on a substrate and dried under heat, UV or IR to obtain a soft and flexible water soluble film, which can be separated from the substrate and then cut into pieces for

30 apply them on the teeth and whiten them.

Example 2

Material

Quantity (% w / w) Function

Hydroxyethyl cellulose

 75% Film forming polymer / thickener

Hydrogen peroxide

5.5% Bleaching agent

Propylene glycol

 5% Moisturizer

Glycerol

 12% Moisturizer

Sodium stannate

2% Stabilizer

Methylparaben

 0.25% Preservative

Dimethicone

 0.25% Technological Assistant

In the preparation of this example an additional 3,000% of purified water is used. Water is introduced into a low shear mixer and is circulated. The methylparaben dissolves in the water and then the mixture is cooled below 25 ° C. At this time the other ingredients (except hydroxyethylcellulose) are added and mixed for another 10 minutes. Hydroxyethylcellulose is added slowly to produce

5 a homogeneous mixture.

The resulting polymer solution is placed on a substrate and dried under heat, UV or IR to obtain a soft and flexible water soluble film, which can then be cut into pieces to be applied on the teeth and bleached. The water soluble film is separated from the substrate before applying it on the teeth.

Clinical studies

10 Clinical studies were conducted to determine the efficacy of the composition of the present invention. The following Table 1 shows the Vita® hue scores after treatment with a composition of the present invention.

Table 1

Evaluation time

Sample size Vita baseline score (before treatment) Vita average tone score (after treatment) Number of hue changes from baseline

Day 8 Day 15

6 6 4.83 4.83 3.25 2.50 1.58 2.33

15 The results show that, with two daily applications of the tooth whitening composition described herein, after 8 days, dental staining is reduced by approximately 1.5 changes in tone. After 15 days of treatment, dental staining has been reduced by more than 2 changes in tone.

The Vita® hue scoring test is the standard test used to determine the degree of teeth whitening due to a particular composition. Specialists are well aware of this test and the conditions under

20 that takes place.

Table 2 shows the results of a clinical evaluation of dental sensitivity after using the composition of the present invention compared to a commercial control on a support. The products were used according to the recommended instructions. The sensitivity was determined by the users through a numerical scale under GPC conditions (good clinical practice). The

25 specialists know this test well.

Table 2

Treatment A - (Test Product)

Evaluation

 n Baseline Score Average score Main changes from baseline

Day 8 Day 15

12 12 0.00 0.00 0.00 0.00 0.00 0.00

Treatment% - (Commercial Control Product)

Evaluation

 n Baseline Score Average score Main changes from baseline

Day 8 Day 15

13 13 0.00 0.00 0.15 0.08 0.15 0.08

Test product: Number of sensitivity notification incidents = zero Control product: Number of sensitivity notification incidents = 3 (23% of test group)

Obviously it is to be understood that the invention should not be limited to the details of the above-described embodiments, which are described by way of example only.

Claims (12)

one.

Dental whitening composition in the form of a pre-formed film for application on the surface of the teeth, said film being formed by at least one bleaching agent together with at least one film forming material, characterized in that said film is soluble in water and is not associated with any support material, the tooth whitening composition further comprising a flavoring ingredient.

2.

Composition according to claim 1, characterized in that it additionally comprises any of the following components, alone or in combination: at least one plasticizer and at least one filler material.

3.

Composition according to claim 1 or claim 2, characterized in that the film-forming polymer is selected from any of the following materials, alone or in combination: polysaccharides, polyvinyl alcohol, polyvinyl pyrrolidone and polymers based on polyacrylic acid.

Four.

Composition according to claim 3, characterized in that the film-forming polymer is derived from cellulose.

5.

Composition according to claim 2, characterized in that the plasticizer is selected from any of the following: polyalcohols and sugar syrups.

6.

Composition according to claim 2 or 5, characterized in that the plasticizer constitutes between 0 and 80% w / w of the total composition.

7.

Composition according to any of the preceding claims, characterized in that the bleaching agent is based on peroxide.

8.

Composition according to claim 7, characterized in that the peroxide is hydrogen peroxide and / or urea peroxide.

9.

Composition according to any of the preceding claims, characterized in that the bleaching agent constitutes between 0.1 and 50% w / w of the total composition.

10.

Composition according to any of the preceding claims, characterized in that it additionally comprises a technological assistant consisting of a silicone-based compound.

eleven.

Use of a tooth whitening composition as described in claim 1 to reduce discoloration of the teeth.

12.

Method for producing a tooth whitening composition according to claim 1, comprising the steps of: preparing an aqueous mixture comprising at least one bleaching agent together with at least one film-forming material and a flavoring ingredient, arranging said mixture on a substrate and allowing Let the mixture dry.