Method of tooth whitening and whitening kit

Abstract

To provide a method of tooth whitening that can strike a balance between securing safety and reduction in treatment time.SOLUTION: A method for whitening teeth of a patient within the living body includes the steps of: creating a whitening composition by mixing hydrogen peroxide with urea peroxide; applying the whitening composition to at least one tooth; and exposing the whitening composition of the tooth to action light, where the step of applying the whitening composition for the tooth is conducted only once.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to methods of tooth whitening and kits that can be used for tooth whitening. [Background technology]

[0002] In recent years, there has been an increasing demand for tooth whitening for the purpose of improving the impression of appearance, etc. Teeth whitening methods generally include bleaching methods that use bleaching agents such as hydrogen peroxide and urea peroxide to bleach teeth. For example, Patent Document 1 discloses a technique for simultaneously etching and bleaching teeth using a bleaching agent that is a mixture of hydrogen peroxide and orthophosphoric acid (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 8-143436 Summary of the Invention [Problem to be solved by the invention]

[0004] However, teeth whitening methods using hydrogen peroxide require repeated reapplication of the bleaching agent because hydrogen peroxide decomposes quickly and loses its whitening effect. Hydrogen peroxide is highly irritating, and care must be taken to prevent the bleaching agent from coming into contact with the gums to ensure safety. However, the task of repeatedly reapplication of the bleaching agent not only entails risks, but also increases the cost of treatment.

[0005] In addition, although urea peroxide is less irritating than hydrogen peroxide, it has the problem that its bleaching performance is lower than that of hydrogen peroxide in the same treatment time, and the treatment time is longer.

[0006] Therefore, an object of the present invention is to provide a teeth whitening method that can ensure safety and shorten the treatment time. [Means for solving the problem]

[0007] In order to achieve the above object, the tooth whitening method of the present invention comprises: A method for whitening a patient's teeth in vivo, comprising the steps of combining hydrogen peroxide and urea peroxide to form a whitening composition, applying the whitening composition to at least one tooth, and exposing the tooth whitening composition to actinic light, wherein the step of applying the tooth whitening composition is performed only once. Effect of the Invention

[0008] According to one embodiment of the present invention, it is possible to provide a teeth whitening method that can ensure safety and shorten the treatment time. [Brief description of the drawings]

[0009] [Figure 1] 1 is an example of a flow diagram of a whitening method according to an embodiment of the present invention. [Diagram 2] 11 is a photograph for explaining the state of the oral cavity before and after whitening when irradiated with actinic light for 20 minutes according to one embodiment of the present invention. [Diagram 3] 11 is a photograph for explaining the state of the oral cavity before and after whitening when irradiated with actinic light for 30 minutes according to one embodiment of the present invention. [Figure 4] 3 is a photograph for explaining the state of the oral cavity before and after whitening when irradiated with actinic light for 20 or 30 minutes according to one embodiment of the present invention. [Diagram 5] 11 is a photograph for explaining the state of the oral cavity before and after whitening to confirm the effect of continuous irradiation with action light according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, a tooth whitening method according to an embodiment of the present invention will be described with reference to the drawings. The tooth whitening method according to this embodiment can be used to whiten teeth discolored by any agent or disease. For example, it can be applied to whiten teeth discolored by stains (e.g., tobacco, coffee, tea and / or food stains), bacteria, genetic predisposition, fluorosis, developmental disorders, trauma, pigments present during the tooth growth stage, etc.

[0011] (Whitening method) FIG. 1 shows an example of a flow diagram of the whitening method according to this embodiment.

[0012] As shown in FIG. 1, the whitening method according to the present embodiment is a method for whitening a patient's teeth in vivo, comprising: A step (S100) of mixing hydrogen peroxide and urea peroxide to prepare a whitening composition; applying the whitening composition to at least one tooth (S120); and exposing the tooth whitening composition to actinic light (S140).

[0013] Each step will now be described in detail.

[0014] The step of preparing a whitening composition (S100) is a step of mixing at least hydrogen peroxide and urea peroxide to prepare a tooth whitening composition.

[0015] Hydrogen peroxide is chemically decomposed and releases active oxygen (hydroxyl radicals). This chemical decomposition is activated by exposure to actinic light and heat. The released active oxygen penetrates the enamel and acts only on the colored substances (organic matter), so teeth can be whitened without changing the structure of the dentin.

[0016] In addition, urea peroxide decomposes in the oral cavity into urea and hydrogen peroxide, and the hydrogen peroxide produced by the decomposition releases active oxygen as described above, so that it can whiten the teeth.

[0017] When using hydrogen peroxide for tooth whitening, hydrogen peroxide decomposes quickly and the tooth whitening effect usually wears off about 8 minutes after application, so the bleaching agent must be reapplied many times. In other words, the application of the bleaching agent, exposure to the actinic light, and removal of the bleaching agent must be repeated several times. This requires the practitioner to devote himself or herself to one patient, which increases chair time and increases labor costs for the technician.

[0018] On the other hand, whitening using urea peroxide has the problem that it takes time for the hydrogen peroxide to break down (for example, it takes about two hours for it to break down completely), which lengthens the treatment time.

[0019] The present inventors have intensively studied the merits and demerits of hydrogen peroxide and urea peroxide, and have found that by using a whitening composition in which they are mixed, sufficient whitening effect can be obtained by applying the whitening composition only once, and the overall treatment time can be significantly shortened. In other words, the inventors have found that in the early stage of whitening (within about 10 minutes after the application of the whitening composition), the whitening effect is mainly derived from hydrogen peroxide, and in the middle to late stages of whitening (from about 10 minutes after the application of the whitening composition to the end of the treatment), the whitening effect is mainly derived from hydrogen peroxide decomposed from urea peroxide.

[0020] In the whitening composition of this embodiment, the mixing ratio of hydrogen peroxide to urea peroxide is preferably within the range of 48:52 (1:1 for a 30% hydrogen peroxide composition: 32% urea peroxide composition) to 16:84 (1:5 for a 30% hydrogen peroxide composition: 32% urea peroxide composition). By keeping it within the above range, the whitening effect mainly derived from the mixed hydrogen peroxide can be obtained, particularly within about 8 to 10 minutes after application of the whitening composition, and the whitening effect mainly derived from the urea peroxide can be obtained after about 10 minutes after application of the whitening composition.

[0021] In this embodiment, hydrogen peroxide with a concentration of 30% and urea peroxide with a concentration of 32% were used, but these concentrations are not limited to these and any appropriate concentration may be used as appropriate so long as it is within the above concentration range.

[0022] The tooth whitening composition may also contain a known visible light responsive photocatalyst. The visible light responsive photocatalyst releases a large amount of electrons when irradiated with light. The released electrons react with hydrogen peroxide to generate a large amount of active oxygen.

[0023] The tooth whitening composition may also include other ingredients, including, but not limited to, known stabilizers (including pH adjusters), thickeners, and gelling agents. The stabilizers may act to stabilize one or more agents against natural or undesirable reactions of the oxidizing agent during use and / or storage. The thickeners are added to facilitate the application of the whitening composition to the teeth and to allow for easier and more uniform application. The gelling agents may prevent evaporation of the gel when exposed to actinic light and may improve hydration of the applied tooth area, thereby reducing patient discomfort.

[0024] In this example, the concentration of hydrogen peroxide in the tooth whitening composition (theoretical effective concentration including hydrogen peroxide derived from urea peroxide) was within the range of 21.33% to 5.95%.

[0025] The step of applying the whitening composition (S120) is a step of applying the prepared whitening composition to the surface of at least one tooth of the patient, and preferably as many teeth as the patient wishes to whiten.

[0026] The method of applying the whitening composition to the patient's teeth is not particularly limited, and any method of applying a known whitening composition can be used. For example, the whitening composition may be applied directly to the patient's teeth using a known application tool, or the whitening composition may be applied to the inside of a known mouthpiece, and the patient may wear the mouthpiece to apply the whitening composition to the patient's teeth.

[0027] The step of exposing the whitening composition to actinic light (S140) is a step of exposing the composition to actinic light in order to accelerate the decomposition of hydrogen peroxide and urea peroxide and the generation of active oxygen.

[0028] The light source for the actinic light is not particularly limited, and any known light source can be used as appropriate. For example, an LED light source, a halogen light source, a metal halide light source, a xenon light source, etc. are preferably used.

[0029] The exposure time of the actinic light is preferably 15 to 40 minutes. When the whitening composition is exposed to the actinic light immediately after application, the exposure time of the actinic light within the above range can provide a whitening effect mainly derived from the mixed hydrogen peroxide within about 8 to 10 minutes from the exposure of the actinic light, and a whitening effect mainly derived from the urea peroxide can be provided after about 10 minutes from the exposure of the actinic light.

[0030] In conventional whitening, teeth are exposed to actinic light multiple times, and a new tooth whitening composition is applied before each exposure to actinic light. However, in the whitening method according to the present embodiment, the step of applying the tooth whitening composition only needs to be performed once. This eliminates the need to reapply the whitening composition multiple times, and exposure to actinic light is also performed by continuous irradiation. This reduces the labor costs involved in the treatment, and also shortens the total treatment time. In the whitening method according to the present embodiment, the tooth whitening composition is applied only once to achieve the desired effect, but it may be applied multiple times.

[0031] (Whitening kit) The present invention provides a whitening kit for carrying out the whitening method according to the present embodiment. The whitening kit according to the present embodiment includes a composition containing hydrogen peroxide and a composition containing urea peroxide.

[0032] In one embodiment, the composition comprising hydrogen peroxide and the composition comprising urea peroxide are not mixed, and may optionally include a device for mixing these compositions.

[0033] The whitening kit according to the present embodiment also includes a preferred mixing ratio of the composition containing hydrogen peroxide and the composition containing urea peroxide to obtain a whitening effect, as well as an instruction manual for determining the exposure time of the whitening composition to actinic light. The whitening kit according to the present embodiment also includes an application tool. The whitening kit according to the present embodiment may also include a light source of actinic light.

[0034] Example 1 The teeth of two female patients in their twenties were cleaned using a commercially available tooth surface cleaning material. After that, Vaseline was applied to the lips of the patients to keep them moist, and a retractor was attached to protect (remove) the lips. The gums and tooth surfaces were then dried using a cotton swab, and the gums were covered with a gum protection resin, which was then hardened by irradiating it with a dental polymerization light for about 15 seconds.

[0035] Urea peroxide (concentration 32%): hydrogen peroxide (concentration 30%) = 5:1 (Formulation Example 1), 3:1 (Formulation Example 2), 1:1 (Formulation Example 3) were mixed to prepare whitening compositions of Formulation Examples 1 to 3.

[0036] The prepared whitening composition was then applied to a mouthpiece, which was then placed in the patient's oral cavity and irradiated with actinic light (Beyond Porous, manufactured by JBA Corporation) for 20 or 30 minutes.

[0037] After the irradiation of the actinic light was completed, the retractor, mouthpiece, and cotton pad were promptly removed from the mouth and the mouth was rinsed. The gum protection resin on the gums was then removed, the mouth was rinsed again, and finally, the mouth was rinsed with a fluoride mouthwash. The whitening procedure was completed by checking whether any foreign objects remained in the mouth.

[0038] FIG. 2 shows a photograph for explaining the state of the oral cavity before and after whitening when the active light is irradiated for 20 minutes. FIG. 3 shows a photograph for explaining the state of the oral cavity before and after whitening when the active light is irradiated for 30 minutes. FIG. 4 shows a photograph for explaining the state of the oral cavity before and after whitening when the active light is irradiated for 20 or 30 minutes. The upper figures in FIG. 2 to FIG. 4 show the state of the oral cavity before whitening, and the lower figures in FIG. 2 to FIG. 4 show the state of the oral cavity after whitening. The right tooth (the tooth on the left side in the figure) in FIG. 2 and FIG. 3 shows the state where the whitening composition of the above-mentioned Formulation Example 1 is applied, and the left tooth (the tooth on the right side in the figure) in FIG. 2 and FIG. 3 shows the state where the whitening composition of the above-mentioned Formulation Example 3 is applied. Furthermore, the right tooth in Figure 4 (the tooth on the left side in the figure) shows what it looks like when the whitening composition of Formulation Example 3 above is applied and exposed to actinic light for 20 minutes, and the left tooth in Figure 4 (the tooth on the right side in the figure) shows what it looks like when the whitening composition of Formulation Example 3 above is applied and exposed to actinic light for 30 minutes.

[0039] In addition, regarding the patient's teeth before and after whitening, the upper central incisors were visually evaluated to see which hue they corresponded to in the A, B, C, D, or W series of the Vita shade guide, which is a tooth color reference table. The right and left central incisors shown in FIG. 2 were both A1 before whitening, but both were W1 after the treatment with the whitening method according to this embodiment. The right and left central incisors shown in FIG. 3 were both A1 before whitening, but both were W1 after the treatment with the whitening method according to this embodiment. Furthermore, the right central incisors shown in FIG. 4 were C1 before whitening, but were W3 after the treatment with the whitening method according to this embodiment. Furthermore, the left central incisors shown in FIG. 4 were C2 before whitening, but were W3 after the treatment with the whitening method according to this embodiment.

[0040] From the results of Figures 2 to 4 and the above-mentioned Vita Shade Guide, it was found that the whitening method according to the present embodiment can reliably whiten the patient's teeth. It was also found that the prescription example containing a large amount of hydrogen peroxide had a higher tooth whitening effect. Furthermore, from the comparison of Figures 2 and 3, and the comparison of the right tooth and the left tooth in Figure 4, it was confirmed that the whitening effect was not lost even when the exposure time of the actinic light was extended by applying the whitening composition only once.

[0041] From the above results, it was found that the whitening method according to this embodiment is capable of obtaining a sufficient whitening effect with only one application of the whitening composition, and is also capable of significantly shortening the overall treatment time.

[0042] Example 2 In order to confirm that a sufficient whitening effect can be obtained by applying the whitening composition only once, the whitening effect was examined using four extracted human teeth as described below.

[0043] After cleaning the extracted human teeth, the whitening composition of the above Formulation Example 3 was applied. Immediately, the teeth were irradiated with actinic light (20 minutes continuous irradiation, 30 minutes continuous irradiation, 10 minutes irradiation x 3 times, 15 minutes irradiation x 2 times). When the teeth were irradiated with actinic light multiple times, the whitening composition was removed before irradiation and reapplied, and then the teeth were irradiated with actinic light.

[0044] Fig. 5 shows photographs for explaining the state of the oral cavity before and after whitening to confirm the effect of continuous irradiation of the action light according to one embodiment of the present invention. The lower figure in Fig. 5 shows the state of the extracted tooth before the whitening method was performed, and the upper figure shows the state of the extracted tooth after the whitening method was performed. The irradiation conditions of the action light in Fig. 5 were 20 minutes continuous irradiation, 30 minutes continuous irradiation, 10 minutes irradiation x 3 times, and 15 minutes irradiation x 2 times from the left side.

[0045] Human extracted teeth before and after whitening were visually evaluated to see which hue they fell into, A, B, C, D, or W, of the Vita shade guide, a tooth color standard chart. The hue, from before to after whitening, was B4 to A2 (20 minutes of continuous irradiation), A3.5 to A1 (30 minutes of continuous irradiation), A3.5 to A2 (10 minutes of irradiation x 3 times), and B4 to B2 (15 minutes of irradiation x 2 times).

[0046] From the results of Fig. 5 and the above Vita Shade Guide, it can be seen that the longer the total exposure time of the actinic light, the higher the whitening effect, and the longer the continuous exposure time, the higher the whitening effect. That is, in conventional whitening, teeth are exposed to actinic light multiple times, and a new tooth whitening composition is applied before each exposure to actinic light. However, in the whitening method according to the present embodiment, the step of applying the tooth whitening composition is only once, but it is found to have a high whitening effect. [Explanation of symbols]

[0047] S100: Producing a whitening composition S120 Applying the whitening composition S140 Exposing the whitening composition to actinic light

Claims

1. 1. A method for in vivo whitening of a patient's teeth, comprising: mixing hydrogen peroxide and urea peroxide to form a whitening composition; applying the whitening composition to at least one tooth; exposing the tooth whitening composition to actinic light; having A method of teeth whitening, wherein the step of applying the tooth whitening composition is performed only once.

2. 10. The method of claim 1, wherein the actinic light exposing step exposes the tooth whitening composition to actinic light for between 15 minutes and 40 minutes.

3. 2. The method for whitening teeth according to claim 1, wherein the mixing ratio of said hydrogen peroxide to said urea peroxide in said whitening composition is within the range of 48:52 to 16:

84.

4. A whitening kit for carrying out the tooth whitening method according to claim 1, comprising: A composition containing hydrogen peroxide and a composition containing urea peroxide. Teeth whitening kit.

5. The whitening composition includes a tool for mixing the hydrogen peroxide-containing composition and the urea peroxide-containing composition, a tool for applying the whitening composition, and an instruction manual for determining the mixing ratio of the hydrogen peroxide-containing composition and the urea peroxide-containing composition to obtain a whitening effect, and the exposure time of the whitening composition to actinic light.

5. The tooth whitening kit of claim 4.

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