KR101936990B1 - Primer of orthodontic dental materials for preventing enamel demineralization and method of manufacturing the same - Google Patents

Abstract

The present invention discloses chlorhexidine (CHX) as an antimicrobial agent in the form of a precursor for the preparation of a primer for use in adhering a tooth correcting device to a tooth surface and a separate disinfectant contained therein. Accordingly, the primer for attaching the orthodontic appliance according to an embodiment of the present invention includes a precursor for preparing a primer for attaching the orthodontic appliance to a tooth; And an antimicrobial agent in the form of a disinfectant added to the precursor for preparing the primer.
The present invention effectively prevents the enamel demineralization and dental caries occurring around the orthodontic appliance during the orthodontic treatment through the growth of the causative bacteria of dental caries and the inhibition of biofilm formation attached around the orthodontic appliance, , It is possible to effectively suppress the weakening of the adhesive strength which occurs when an antimicrobial agent is contained in the orthodontic appliance, thereby preventing the enamel demineralization and dental caries occurring during the orthodontic treatment, and maintaining the strength of the tooth surface attachment of the orthodontic appliance.

Description

Technical Field [0001] The present invention relates to a primer for priming an apparatus for preparing an orthodontic appliance having an enamel demineralization inhibiting effect and a method for manufacturing the same,

More particularly, the present invention relates to a primer for attaching an orthodontic appliance having an enamel decalcification inhibiting effect containing an antimicrobial agent and a method for producing the primer.

Adhesive primers and adhesives are used to attach the orthodontic appliance to the surface of the teeth. The primer is used to provide adequate bonding strength between the tooth and the bracket of the orthodontic appliance.

To attach the orthodontic appliance to the tooth surface, the tooth is completely dried and then the primer having hydrophobicity is applied to the tooth surface, and then the tooth surface to which the primer is applied and the orthodontic appliance are attached using the adhesive.

Enamel demineralization generally occurs at the interface between the tooth surface and the bracket of the orthodontic appliance during the orthodontic treatment procedure using the orthodontic appliance. Enamel demineralization at this interface is caused by species such as Streptococcus mutans (S. mutans ) , a biofilm bacterium that causes tooth decay (cavities) in teeth.

Oral biofilm shows increased virulence when biofilm bacteria remain in the mouth without being removed by antimicrobial agents and mechanical washing. Therefore, enamel deliming can be prevented by inhibiting the formation of a bacterial biofilm on the tooth surface.

A variety of methods have been studied to reduce the incidence of caries caused by enamel demineralization that occurs when a tooth orthodontic device is attached to the enamel surface (see Patent Document 1). A typical method is to use an antimicrobial agent. Natural ingredients extracted from medicinal plants may be useful as antimicrobial agents. For example, chlorhexidine (CHX) is widely used to chemically control plaque, and chlorhexidine (CHX) inhibits biofilm formation on tooth surfaces. In another example, Ursolic Acid (UA) is a relatively non-toxic triterpenoid compound with anticariogenic activity.

Fluoride and chlorhexidine (CHX) have been mainly mentioned as antimicrobial agents, and methods of using antibacterial agents in adverse formulations used for attaching bracket devices have been mainly studied.

However, there is a problem in that the method of using the antiseptic mixed with the adhesives can maintain the antibacterial effect only for a very short time and reduces the adhesive strength to the tooth surface of the bracket device.

Patent Document 1: Korean Patent Publication No. 10-1734756

It is an object of the present invention to provide an antimicrobial agent which is used for attaching an orthodontic appliance to a tooth, thereby preventing the bonding strength of the orthodontic appliance from being weakened, preventing dental caries, The present invention also provides a method for preparing a primer and a primer for attaching the orthodontic appliance, which is capable of maintaining the adhesive strength of the orthodontic appliance for a long period of time while having an enamel decalcification inhibiting effect.

According to an aspect of the present invention, there is provided a primer for attaching a dental prosthesis, comprising: a precursor for preparing a primer to be attached to a tooth; And an antimicrobial agent added in the precursor for preparing the primer.

The orthodontic appliance refers to various types of devices used for orthodontics.

In one embodiment, the primer for preparing a primer may be a Transbond XT primer (TX) having hydrophobicity.

In one embodiment, the antimicrobial agent preferably comprises chlorhexidine (CHX) or uric acid (UA).

In one embodiment, the concentration of chlorhexidine (CHX) may be 0.3 w / v%.

A method for preparing a primer for attaching a tooth correcting device according to an embodiment of the present invention comprises: preparing a mixture by adding an antimicrobial agent to a precursor for preparing a primer; And stirring the mixture.

In one embodiment, the primer for preparing a primer may be a Transbond XT primer (TX) having hydrophobicity.

In one embodiment, the antimicrobial agent preferably comprises chlorhexidine (CHX) or uric acid (UA).

In one embodiment, the concentration of chlorhexidine (CHX) may be 0.3 w / v%.

Stirring the mixture in one embodiment may include stirring at room temperature for 12 hours.

In one embodiment, the step of adding an antimicrobial agent to the primer-forming precursor to prepare a mixture may include the step of adding 3 mg of chlorhexidine (CHX) to 1 ml of Transbond XT primer (TX) to prepare the mixture have.

The present invention can prevent formation of bacterial biofilm by incorporating chlorhexidine (CHX) into a primer for preparing a primer, thereby preventing demineralization of enamel, which occurs when a tooth correcting device is attached to a tooth.

In addition, by including chlorhexidine (CHX) in the precursor for preparing a primer, bacterial biofilm formation can be inhibited, dental caries can be prevented, and the antibacterial ability can be maintained for a long time.

The present invention can prevent the bonding strength of the apparatus for orthodontic treatment from being weakened compared with the system in which an antimicrobial agent is mixed with the adhesive even though it has an antibacterial effect and the bonding strength between the tooth surface and the orthodontic appliance can be maintained for a sufficiently long time .

FIG. 1A is a graph showing the growth rates of Streptococcus mutans strains with time for each of the primers not added and the types of primers added.
FIG. 1B is a graph showing the growth rates of Streptococcus mutans after thermocycling treatment according to time for each of the primers not added and the primers added. FIG.
FIG. 2 is a flow chart for explaining a method of manufacturing a primer for attaching the orthodontic appliance according to an embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. Wherein like reference numerals refer to like elements throughout.

The primer for attaching the orthodontic appliance according to an embodiment of the present invention may include a precursor for preparing a primer and an antimicrobial agent in the form of a separate disinfectant.

The precursor for primer preparation is a material used in the calibration process for attaching a tooth alignment device to a tooth surface. For example, the precursor for preparing a primer may be a hydrophobic Transbond XT primer (TX) having a hydrophobic property, but it is not limited to a precursor for producing a primer having a hydrophobic property.

An antimicrobial agent in the form of a disinfectant may be added to the precursor for preparing the primer. Chlorhexidine (CHX) or uric acid (UA) may be used as an antimicrobial agent in the form of a disinfectant to be added to the precursor for preparing a primer, but the kind of antimicrobial agent in the form of a disinfectant is not limited. When an antibacterial agent in the form of a disinfectant is added to the precursor for preparing a primer, the bonding strength between the bracket and the tooth surface of the orthodontic appliance remains the same as in the prior art, and dental caries and enamel demineralization Can be prevented.

The proper concentration of the antimicrobial agent in the form of a disinfectant contained in the precursor for primer preparation is important. This is because, when the concentration of the antimicrobial agent is low, the antimicrobial activity is low, and when the concentration of the antimicrobial agent is high, the mechanical properties of the orthodontic appliance may be deteriorated. For example, the concentration of chlorhexidine (CHX) may be 0.3 w / v%.
The concentration "0.3 w / v%" in the present specification is a value using a concentration unit of a typical w / v%, which may mean the same concentration value as "3 mg / ml ".
When the concentration of chlorhexidine (CHX) is not 0.3 w / v%, it is impossible to uniformly mix chlorhexidine (CHX) and Transbond XT primer (TX) while maintaining shear bond strength, and chlorhexidine (CHX ) Is 0.3w / v%, the antimicrobial activity of Streptococcus mutans causing dental caries is the most excellent.

FIG. 2 is a flow chart for explaining a method of manufacturing a primer for attaching the orthodontic appliance according to an embodiment of the present invention.

Referring to FIG. 2, the method for preparing a primer for attaching a tooth correcting device according to an embodiment of the present invention includes a step (S100) of adding a disinfectant-type antimicrobial agent to a primer for preparing a primer to produce a mixture (S200 ).

In order to prepare a primer for attaching the orthodontic appliance, an antimicrobial agent in the form of a disinfectant is added to a precursor for preparing a primer to prepare a mixture (S100). For example, a mixture can be prepared by adding 3 mg of chlorhexidine (CHX) to 1 ml of Transbond XT primer (TX).

Next, the mixture is stirred so that the precursor for preparing the primer and the chlorhexidine (CHX) in the form of a disinfectant are uniformly mixed. For example, the mixture may be stirred at room temperature for 12 hours to ensure uniform mixing of the primer-forming precursor and chlorhexidine (CHX).

sample preparation

A Transbond XT primer (TX, Comparative Example 1) of 3M Unitek, a conventional primer used for attaching the orthodontic appliance to a tooth, and 1 ml of Transbond XT primer (TX) (TXX-CHX), 1 ml of Transbond XT primer (TX) (Sigma-Aldrich Co., Ltd.) was added with 3 mg of chlorhexidine (CHX) UA) was added and stirred at room temperature for 12 hours to prepare a sample (Comparative Example 2, TX-UA).

Bacterial culture, minimum inhibition concentration test and minimum antibacterial concentration test

S. mutans UA159 ( Streptococcus mutans serotype c) was cultured at 37 ° C in an aerobic atmosphere with a 5% CO 2 concentration. As the medium, a liquid culture medium of BHI (brain heart infusion) broth (MB-B1008) of Becton Dickinson, which is generally used for culturing various microorganisms including bacteria, yeast and fungi, was used. S. mutans UA159 was cultured using 96-well plates of Corning Incorporated, and each mutant was allowed to have 1 × 10 ⁶ CFU / ml of S. mutans UA159.

In order to measure the minimum inhibitory concentration (MIC), the final concentrations of the primers (Comparative Example 1, Comparative Example 1 and Example 1) were 8, 16, 32, 64, 128, 256, Ml < / RTI > The wells contained ampicillin used as a positive control and the final concentration of ampicillin was adjusted to 100 μg / ml. The medium containing no dimethyl sulfoxide (DMSO) and the medium containing dimethyl sulfoxide (DMSO) were used in a double-negative control. After 24 hours of incubation, the lowest fryer concentration that significantly inhibited growth was determined as the minimum inhibitory concentration (MIC) value.

To determine the minimum antimicrobial concentration (MBC) value, 100 uL of bacterial medium was diluted 10 to 1000 times from each well with a minimum inhibitory concentration (MIC) value determined as described above, and each bacterial strain strain on a BHI agar plate. The agar plates were incubated at 37 DEG C for 48 hours and the number of colonies counted. Concentration to remove 99.9% of bacteria was considered as the minimum antibacterial concentration (MBC). The minimum inhibitory concentration (MIC) and minimum antimicrobial concentration (MBC) were determined according to the American National Committee for Clinical Laboratory Standards (NCCLS). Minimum inhibitory concentration (MIC) and minimal antibacterial concentration (MBC) tests are widely known methods for testing the sensitivity of antimicrobials to pathogenic bacteria. A low value of minimum inhibitory concentration (MIC) and minimum antibacterial concentration (MBC) indicates that the antibacterial activity (antimicrobial activity) is excellent.

As a result of the test, the minimum inhibitory concentration (MIC) value of Example 1 was 32 占 퐂 / ml while the minimum inhibitory concentration (MIC) value of Comparative Example 1 and Comparative Example 2 was 1024 占 퐂 / ml. In addition, the minimum inhibitory concentration (MIC) values of Comparative Example 1 and Comparative Example 2 exceeded the test limit of 1024 占 퐂 / ml, while the minimum antibacterial concentration (MBC) value of Example 1 was 32 占 퐂 / I did. These results indicate that the antimicrobial strength of Example 1 is far superior to that of Comparative Example 1 and Comparative Example 2. In Example 1, more than 99.9% of Streptococcus mutans was eradicated above 32 / / ml, but Comparative Example 1 and Comparative Example 2 showed no effect on Streptococcus mutans .

Growth analysis test

Growth assays were performed using 96-well plates to analyze the effect on S. mutans . Prior to the analysis, the primer was applied to the cell of the plate and lighted at the top for 20 seconds, and the LED was irradiated at a lower intensity of about 1000 ㎷ / ㎠ intensity for 20 seconds. For comparison of growth rates, S. mutans UA159 was diluted 1: 100 in BHI broth and cultured. Bacterial suspensions injected with S. mutans UA159 were incubated at 37 ° C with primers.

In order to monitor the growth, the absorbance at 600 nm was recorded for 72 hours at regular intervals using a microplate reader Infinite F200 pro. In order to analyze the effect of water aging on the antimicrobial activity and to simulate normal aging in the oral cavity as the antimicrobial activity can be gradually reduced as the antimicrobial agent is liberated from the primer into the oral cavity, The plates were thermocycled in water. The thermocycling process was carried out using a thermocycler and was set to heat transfer for 5 seconds every 20 seconds and the immersion temperature range in water was 55 ° C at 5 ° C. To observe the effect on water aging, 5,000 cycles of thermocycling were carried out for 7 days in order to cope with aging for 6 months physically.

To remove cellular debris, saliva samples were centrifuged at 3500 g for 10 min and the resulting supernatnat was used after filter-sterilization. Biofilm analysis was performed using 96-well-plates, and the primers were applied to the same plate as described above.

To assess biofilm formation, S. mutans UA159 was grown in a semi-defined biofilm medium containing 18 mM glucose and 2 mM sucrose as a carbohydrate source. Overnight incubated S. mutans was transferred to preheated BHI and grown at 37 ° C in an aerobic atmosphere with 5% CO 2 concentration until the midexponential phase OD ₆₀₀ = 0.5. The cultures were diluted 100-fold in preheated biofilm medium.

For saliva coating, 60 타 of saliva was added to the wells controlled with the primer, and biofilm analysis was performed. Plates were incubated for 2 h at 37 ° C with careful shaking and washed twice with phosphate-buffered saline at pH = 7.2. After air drying for 30 minutes, 150 占 퐇 of cell suspensions were added. All plates were incubated for 24 hours at 37 占 폚 in an aerobic atmosphere with a 5% CO 2 concentration. Plates were washed twice with 150 μl of sterile distilled water to remove planktonic and loosely adherent cells. The attached bacteria were stained with 50 [mu] l of crystal violet for 15 minutes. After washing twice with 150 μl of water, the attached dye was extracted from 200 μl of ethanol having a concentration of 99% from the stained cells. Biofilm formation was quantitated by measuring adsorption at 600 nm through a spectrophotometer. The same experiment was repeated after the thermocycling process.

FIG. 1A is a graph showing the growth rates of Streptococcus mutans strains with time for each of the primers not added and the types of primers added. FIG. 1B is a graph showing the growth rates of Streptococcus mutans strains, FIG. 2 is a graph showing the growth rate of Streptococcus mutans according to time for each type of primer after thermocycling treatment. FIG. [Table 1] shows the formation of a biofilm by Streptococcus mutans in the case where the primer is not added and the type of the added primer (Comparative Example 1, Comparative Example 2 and Example 1) The results are shown in Table 1.

primer Cycling Biofilm Formation (Mean ± SD) No primer control
No cycling 8.86 ± 0.40 Thermocycling 8.85 ± 0.23 TX (Comparative Example 1)
No cycling 7.56 + - 0.34 Thermocycling 7.55 0.35 TX-UA (Comparative Example 2)
No cycling 7.29 ± 0.26 Thermocycling 7.81 ± 0.36 TX-CHX (Example 1)
No cycling 0.25 ± 0.81 Thermocycling 0.00 ± 0.00

Referring to FIGS. 1A, 1B, and 1, in the case of Comparative Example 1 and Comparative Example 2, the growth rate was slightly increased at the initial stage compared to the case where the primer was not used (No primer control) There was no significant difference with other groups after.

In addition, it can be confirmed that there is a considerable difference in the degree of inhibition of the formation of biofilm by Streptococcus mutans depending on the kind of the primer. Compared to the case where no primer was used (No primer control), in case of Comparative Example 1 (TX), Comparative Example 2 (TX-UA) and Example 1 (TX-CHX), S. mutans ) Significantly inhibits the formation of biofilm. Although there is no significant difference in the degree of inhibition of biofilm formation between Comparative Example 1 and Comparative Example 2, it can be confirmed that Example 1 completely inhibits biofilm formation by Streptococcus mutans . In addition, it can be seen that the thermocycling process does not have a great influence on the formation of the biofilm, which means that Example 1 exhibits strong antimicrobial activity regardless of the heat cycle treatment.

1A and 1B, it can be seen that the formation of a biofilm by Streptococcus mutans was inhibited even though time elapsed in Example 1, which indicates that Example 1 has a long-term antimicrobial activity Respectively.

Shear bond strength and adherence test

After washing the front teeth of the healthy bovine, 48 pieces of bovine enamel were prepared using a punching machine so as to have an 8 × 3 mm size. The enamel pieces were inserted into the acrylic mold with labial surfaces parallel to the acrylic mold so as to be parallel during the shear bond test. The front teeth were randomly grouped into three groups. The bonding surface of the front teeth was acid etched with 32% phosphoric acid gel for 20 seconds, washed with water for 30 seconds, and air dried until the charring appeared white.

Comparative Example 1, Comparative Example 2 and Example 1 were each applied with a thin layer on the acid etched surface and air dried. A maxillary incisor bracket was attached to the labial surfaces of the front teeth and exposed to light for 20 seconds. After attachment, the front teeth were thermally cycled and shear bond strength was measured. An occlusogingival load was applied using a plunger, and a shear load occurred at the interface between the bracket and the forearm. The maximum load was recorded in kgf and converted to units of Mpa (nominal surface area, 9.91 mm 2). The shear bond strength data are shown in Table 2 below.

After the bonding strength test, the adhered surface was magnified 10 times by using a stereomicroscope. The amount of adherence remaining on the enamel surface was scored using the adhesive remnant index (ARI). The data for ARI are shown in [Table 3] below.

[Table 2] shows comparison data of shear bond strength between different primers, and [Table 3] shows frequency and distribution of ARI of different primers.

TX (Comparative Example 1) TX-UA (Comparative Example 2) TX-CHX (Example 1) Shear bond strength (Mpa) 10.57 ± 1.81 12.09 + - 2.64 11.46 + - 2.30 Range (Rang) 7.77 ~ 14.51 8.84 to 17.62 8.02-15.36

Type of primer ARI 0 One 2 3 TX (Comparative Example 1) 5 6 One 4 TX-UA (Comparative Example 2) 4 5 0 6 TX-CHX (Example 1) 5 4 2 5

In Table 3, TX of Comparative Example 1 is a 3M Transbond XT primer. The TX-UA of Comparative Example 2 is a Transbond XT primer containing 3 mg / ml Ursolic Acid (UA). Example 1, TX-CHX, is a Transbond XT primer supplemented with 3 mg / ml of chlorhexidine (CHX).

A value of '0' in the ARI indicates that no adherence is present in the tooth, '1' means that the adhesive region of the enamel applied by the adherence is less than half, '2' means that the adherence of enamel '3' indicates a state in which the entire area of the enamel is coated with adhesives.

Referring to Table 2, it can be seen that the bonding strength between the primers (Comparative Example 1, Example 1 and Comparative Example 2) did not change much. Referring to Table 3, it can be seen that there is no significant change in the ARI value among the primers.

The absence of significant changes in the ARI number means that there is no particular difference in debond patterns between the primers, and these results indicate that Example 1 or a uric acid (UA) primer with chlorhexidine (CHX) Indicating that the added primer, Comparative Example 2, did not affect the physical properties of the existing primer (Comparative Example 1). This confirms that the physical properties are not changed even when chlorhexidine (CHX) or uric acid (UA) is added to the conventional primer (Comparative Example 1).

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims. Accordingly, the true scope of the present invention should be determined by the following claims.

Claims (10)

delete delete delete delete Preparing a mixture by adding an antimicrobial agent to the precursor for preparing a primer in the form of a disinfectant; And
A method for preparing a primer for attaching a dental prosthesis, comprising the step of stirring the mixture,
The precursor for preparing a primer is a Transbond XT primer (TX) having hydrophobicity,
Stirring the mixture comprises stirring at ambient temperature for 12 hours,
The step of adding an antimicrobial agent to the precursor for preparing a primer in the form of a disinfectant to prepare a mixture comprises adding 3 mg of chlorhexidine (CHX) to 1 ml of Transbond XT primer (TX)
Wherein the antimicrobial agent is chlorhexidine (CHX) at a concentration of 0.3 w / v%.
delete delete delete delete delete

Images